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91.
The recent flooding in the North–East of Scotland has highlighted issues around climate change due to significant changes in duration, severity and volume of precipitation events. The Planning (PA) and Flood Authorities (FA) often do not have the capacity or resources to review and check the accuracy and robustness of the SUD schemes nor the calculations submitted by developers. This study demonstrates the development and application of an Independent Hydrology Audit (IHA) service aimed at auditing and reviewing ‘in principle’ planning applications from the aspect of flooding risk to the wider community the development is located within. The output of this service is to establish a more accurate representation of surface water impact from developments through the use of adequate green/blue infrastructure, provide a greater assurance to the communities at risk of flooding, and help the PA and FA meet their statutory obligations at the initial stage of planning.  相似文献   
92.
A vehicle exposed to flooding, after losing stability, becomes buoyant and may be washed away with potential injuries and fatalities. Such vehicles cause additional disruption to traffic that is already affected by flooding, which may lead to substantial indirect economic impact, especially in urban areas. Therefore, the analysis of the stability of vehicles exposed to flooding is important in order to make decisions to reduce damages and hazards. In this research, based on an experimental campaign that included a range of twelve car models, a new methodology to obtain the stability threshold for any real vehicle exposed to flooding is developed. A stability coefficient (SCmod) is derived with which the vehicles can be sorted by stability against water flows and their stability functions may be determined. The experiments were conducted with three different model scales (1:14, 1:18 and 1:24) and involved analysis of both friction and buoyancy effects, which made this the most comprehensive research study to date. This methodology enables the definition of a stable area in the flow depth-velocity domain for any real vehicle. A tool is provided that decision-makers in the field of urban flood risk management can employ and after defining a design vehicle they can obtain its corresponding stability threshold.  相似文献   
93.
The above article was published in Volume 18, Issue 6, Pages 493–504, (October 2005). A number of imperfections were subsequently identified and have been corrected below. On page 497, the following equation has been corrected to: On page 501, the following equation has been corrected to: On page 502, the following equation has been corrected to:   相似文献   
94.
95.
An original modeling framework for assessment of climate variation and change impacts on the performance of complex flood protection system has been implemented in the evaluation of the impact of climate variability and change on the reliability, vulnerability and resiliency of the Red River Basin flood protection system (Manitoba, Canada). The modeling framework allows for an evaluation of different climate change scenarios generated by the global climate models. Temperature and precipitation are used as the main factors affecting flood flow generation. System dynamics modeling approach proved to be of great value in the development of system performance assessment model. The most important impact of climate variability and change on hydrologic processes is reflected in the change of flood patterns: flood starting time, peak value and timing. The results show increase in the annual precipitation and the annual streamflow volume in the Red River basin under the future climate change scenarios. Most of the floods generated using three different climate models had an earlier starting time and peak time. The assessment of the performance of Red River flood protection system is based on the flood flows, the capacity of flood control structures and failure flow levels at different locations in the basin. In the Assiniboine River Basin, higher reliabilities at downstream locations are obtained indicating that Shellmouth reservoir plays an important role in reducing downstream flooding. However, a different trend was identified in the Red River Basin. The study results show that flood protection capacity of the Red River infrastructure is sufficient under low reliability criteria but may not be sufficient under high reliability criteria.  相似文献   
96.
97.
The objective of this investigation is to assess the influence of graphite reinforcement on tribological behavior of ZA-27 alloy. The composite with 2 wt% of graphite particles was produced by the compocasting procedure. Tribological properties of unreinforced alloy and composite were studied, using block-on-disk tribometer, under dry and lubricated sliding conditions at different specific loads and sliding speeds. The worn surfaces of the samples were examined by the scanning electron microscopy (SEM). The obtained results revealed that ZA-27/graphite composite specimens exhibited significantly lower wear rate and coefficient of friction than the matrix alloy specimens in all the combinations of applied loads (F n ) and sliding speeds (v) in dry and lubricated tests. The positive tribological effects of graphite reinforcement of ZA-27 in dry sliding tests were provided by the tribo-induced graphite film on the contact surface of composite. In test conditions, characterized by the small graphite content and modest sliding speeds and applied loads, nonuniform tribo-induced graphite films were formed leading to the increase of the friction coefficient and wear rate, with increase of the sliding speed and applied load. In conditions of lubricated sliding, the very fine graphite particles formed in the contact interface mix with the lubricating oil forming the emulsion with improved tribological characteristics. Smeared graphite decreased the negative influence of F n on tribological response of composites, what is manifested by the mild regime of the boundary lubrication, as well as by realization of the mixed lubrication at lower values of the v/F n ratio, with respect to the matrix alloy.  相似文献   
98.
Binary and ternary L10 type titanium alloys were rapidly quenched into thin foils by the hammer-anvil quenching technique. The nominal alloy compositions include Ti1-xAlx and (Ti1-xAlx)100-@#@ yMy, wherex = 0.5 to 0.6; y= 1 to 4; and M is V, Cr, Mn, Fe, Co, Ni, and Ge. Lattice parameters of Ll0 phases in these alloys were studied by X-ray diffractometer using the foils and their powders. Simultaneously, long-range order parameters of these Ll0 phases in the as-quenched foils and the annealed powders were determined from the superlattice intensity measured by X-ray diffractometer. Rapid quenching suppresses long-range ordering (S) during solidification and, thereby, reduces lattice distortion (c/a) in Ll0 titanium alloys. A small amount of alloying element has a large effect on thec/a ratio. The atomic size effect and probably substitutional site preference play an important role in such ac/a reduction. From the density measurement, it is found that antisite defects are a predominant mode in Al-rich off-stoichiometric TiAl compound alloys. Determined long-range order value is significantly low in as-quenched binary TiAl due to rapid quenching, and the highest ordering occurs at as-quenched Ti45Al55 alloy. The relationship betweenc/a andS in Ll0 Ti45Al55 may be written asc/a = 1 + 0.025 ·S.  相似文献   
99.
The effects of the simple composition-dependent combining rules (conventional, Adachi-Sugie and van Laar-Stryjek-Vera-type) and Huron-Vidal-NRTL mixing rules and different cubic equations of state (Redlich-Kwong, Soave-Redlich-Kwong, Peng-Robinson and Peng-Robinson-Stryjek-Vera) on excess molar volume correlation are examined. The results obtained for some asymmetric non-ideal mixtures indicate very good agreement between correlated and experimental data in all cases when Huron-Vidal-NRTL mixing rules are coupled with the Peng-Robinson-Stryjek-Vera equation of state.  相似文献   
100.
Reliability programming formulations offer a family ofexplicit stochastic models for planning the operationof complex water resources systems. These models usecumulative probability distributions of the sum ofinflows to characterize their variability in theplanning period. Applicability of these models for avariety of problems has been limited, mainly due tothe assumption of independence between inflows indifferent time periods that leads to the derivation ofconservative operating policies. This paper presentsthree new approaches to overcome this limitation. Theperformance of the proposed approaches is demonstratedthrough comparison of the operating policies derivedfrom these approaches and the Independent Approach. Operational planning of the Manitoba Hydro energygeneration system, a predominantly hydro-based utilitycompany in Manitoba (Canada), is used as the case study.  相似文献   
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