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1.
The ability of landscape architectural projects to mitigate the worst effects of climate change will depend upon designed ecological systems. These systems will be built with plants. Despite the recognition of ecology as an essential driver of landscapes, the professionals of landscape architecture too often lack the knowledge and practical skills to create robust vegetative systems. New approaches and tools are required. This article outlines principles and methods for designing biodiverse plant systems for urban sites. Planting methods that increase species richness, functional diversity, and spatial complexity are emphasized as a way of developing more resilient plantings. Selecting species with similar evolutionary adaptions to stress, disturbance, and competition—as well as creating multi-layered compositions of diverse plant morphologies—allows designers to create compatible, long-lived plant mixes. To balance the increased visual complexity of diverse plant mixes, the article explores design techniques to make plantings more appealing to the public. The strategies explored here are based on the projects, experience, and research of Phyto Studio, a Washington, D.C. based studio. The methods build on work described in the author’s book, Planting in a Post-Wild World, an exploration of how to create designed plant communities.  相似文献   
2.
New mobile computing technologies require new paradigms for infrastructure and interaction with mobile and networked devices. For building smart mobile companions for new intelligent services, a number of challenges have to be addressed. We argue that artificial intelligence is a key to a new generation of mobile systems. In this introduction to AI in mobile systems, we present some of the challenges and solutions in this exciting field of research.  相似文献   
3.
A new concept for using a ferroelectric field effect transistor in a memory configuration is presented without the requirement of a negative voltage or an erase operation. The transistor is designed so that the accumulation sets in at a lower gate source voltage making it possible to reverse the polarization without applying a negative pulse to the gate.  相似文献   
4.
Using an optical system made from fused silica catalogue optical components, third‐order nonlinear microscopy has been enabled on conventional Ti:sapphire laser‐based multiphoton microscopy setups. The optical system is designed using two lens groups with straightforward adaptation to other microscope stands when one of the lens groups is exchanged. Within the theoretical design, the optical system collects and transmits light with wavelengths between the near ultraviolet and the near infrared from an object field of at least 1 mm in diameter within a resulting numerical aperture of up to 0.56. The numerical aperture can be controlled with a variable aperture stop between the two lens groups of the condenser. We demonstrate this new detection capability in third harmonic generation imaging experiments at the harmonic wavelength of ~300 nm and in multimodal nonlinear optical imaging experiments using third‐order sum frequency generation and coherent anti‐Stokes Raman scattering microscopy so that the wavelengths of the detected signals range from ~300 nm to ~660 nm.  相似文献   
5.
Sequencing problems and especially flowshop sequencing problems have been broadly discussed in literature. But usually the effect of limited buffer storage is ignored, although in industrial production or computer architecture the amount of available buffer storage has an important influence on the performance of the system. This paper presents a systematic overview of how to formulate flowshop problems with limited buffer storage as well as several heuristics to compete with this class of problems. Numerical experiences are also described.  相似文献   
6.
This paper presents data on the ratios of acetylated to p -coumaroylated anthocyanins of authentic and unadulterated trade samples of 71 Cabernet Sauvignon and 40 Portugieser winegrape varieties. The relative peak areas of nine characterising anthocyanins were determined by a standardised and validated HPLC-method. The 95%-confidence ranges calculated from the data ranged from 2.9 to 5.7 for the Cabernet Sauvignon wines and from 0.7 to 1.7 for the Portugieser wines. The rule that individual anthocyanin components are normally distributed was also confirmed for wines vinified from Gamay and Kadarka (Gamza) grape varieties.  相似文献   
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8.
Chemical and functional properties of various blends of phosphate were examined and compared with the conventional phosphate (M-CP: a mechanical blend [50:50] of sodium tripolyphosphate [STPP] and tetrasodium pyrophosphate [TSPP]). Regardless of solution temperature and brine concentration, the solubilities of various blends of phosphates, especially M-1 (a mechanical blend [50:50] of tetrapotassium pyrophosphate and STPP), M-LC (a long-chained sodium hexametapolyphosphate [SHMP] treated with trisodium phosphate [TSP]) and M-MC (a middle-chained SHMP treated with TSP), except for C-S (a chemical blend [50:50] of STPP and TSPP for faster/higher solubility) and C-V (a chemical blend [50:50] of STPP and TSPP for higher viscosity), were higher than that of M-CP. The scanning electronic microscopic image revealed that the structures of various blends of phosphate were quite different. Comparing with M-CP, C-V was superior in viscosity, water retention ability (WRA), emulsifying activity and cooking stability. M-1 was superior in WRA compared to M-CP.

PRACTICAL APPLICATIONS


Conventional blending for phosphates is typically made through simple mechanical mixing. In our study, we featured chemically blended phosphates and found that some of them demonstrated superior functional properties. With this advantage, the use of chemically blended phosphate could reduce the usage level while achieving a similar or better performance.  相似文献   
9.
The control of pH is one of the most difficult challenges in the process industry because of the severe nonlinearities and high precision required in manipulating the flow rate. The Wiener model, which consists of a linear dynamic element followed by a nonlinear static element, is used for representing such nonlinear processes. Piecewise continuous polynomials are used for mapping the nonlinear static gain accurately. A nonlinear PI controller was designed based on the Wiener model. Simulation results on the nonlinear mathematical model are presented to highlight the superior performance of the Wiener model based nonlinear PI controller in comparison to that of the local linear PI controller. The performance of the nonlinear PI controller was further improved upon by using the method of inequalities to obtain a single set of PI controller settings that takes into account the parametric variations in the linear dynamic element at different operating points. Simulation and experimental results are presented to support the work.  相似文献   
10.
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