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31.
BATCH-DIST is a general-purpose simulation package for the design, simulation and optimization of multicomponent, multifraction batch distillation columns operating under different modes (constant reflux, variable reflux and optimal reflux policy). The package includes simulation models of varying degrees of complexity and rigor; efficient but simplified models (based on short-cut methods) for preliminary design and rapid analysis of column behavior, and rigorous models (based on solution of transient heat and mass balance differential equations) for verification and detailed column design. Besides simulation and design, BATCH-DIST can also accomplish optimization and optimal control of columns. Coded in Fortran 77, the package is flexible and user-friendly. BATCH-DIST has been extensively tested with benchmark cases involving binary and multicomponent systems, with nonideal behavior and in columns with appreciable holdup effects. Such test cases have clearly demonstrated that predictions of the simplified models in the package compare well with those of the rigorous models. This powerful and comprehensive package is expected to be computationally more efficient than existing packages.  相似文献   
32.
The optical code division multiple access (OCDMA), the most advanced multiple access technology in optical communication has become significant and gaining popularity because of its asynchronous access capability, faster speed, efficiency, security and unlimited bandwidth. Many codes are developed in spectral amplitude coding optical code division multiple access (SAC-OCDMA) with zero or minimum cross-correlation properties to reduce the multiple access interference (MAI) and Phase Induced Intensity Noise (PIIN). This paper compares two novel SAC-OCDMA codes in terms of their performances such as bit error rate (BER), number of active users that is accommodated with minimum cross-correlation property, high data rate that is achievable and the minimum power that the OCDMA system supports to achieve a minimum BER value. One of the proposed novel codes referred in this work as modified random diagonal code (MRDC) possesses cross-correlation between zero to one and the second novel code referred in this work as modified new zero cross-correlation code (MNZCC) possesses cross-correlation zero to further minimize the multiple access interference, which are found to be more scalable compared to the other existing SAC-OCDMA codes. In this work, the proposed MRDC and MNZCC codes are implemented in an optical system using the optisystem version-12 software for the SAC-OCDMA scheme. Simulation results depict that the OCDMA system based on the proposed novel MNZCC code exhibits better performance compared to the MRDC code and former existing SAC-OCDMA codes. The proposed MNZCC code accommodates maximum number of simultaneous users with higher data rate transmission, lower BER and longer traveling distance without any signal quality degradation as compared to the former existing SAC-OCDMA codes.  相似文献   
33.
In this paper, a novel fuzzy dynamic routing and wavelength assignment technique is proposed for a wavelength division multiplexing optical network to achieve the best quality of network transmission. This paper proposes a novel quality of service aware fuzzy logic controlled dynamic routing and wavelength assignment algorithm (QoS-FDRWA), where the optimum path is chosen by a fuzzy rule-based inference system. The proposed fuzzy routing technique incorporates optical network transmission attributes such as latency, physical length of the link, data packet loss, number of hops, and wavelength availability status in the path.  相似文献   
34.
Multi-agent optimization method is a nature-inspired framework that supports the cooperative search of an optimal solution of an optimization problem by a group of algorithmic agents connected through an environment with certain predefined information sharing protocol. In this work, we propose a novel heterogeneous multi-agent optimization (HTMAO) framework. The proposed framework is validated using a set of benchmark problems a real-world synthesizing radioactive waste blending problem. The optimal radioactive waste blending problem is formulated as a mixed integer nonlinear programming. The total frit used for vitrification process is minimized subject to thermodynamic properties and process model constraints. The model simultaneously determines the optimal decisions that include the combination of the waste tanks that form each waste blend and the amount of frit needed for the vitrification of each waste blend. In developing the HTMAO framework, efficient ant colony optimization algorithms; efficient simulated annealing; efficient genetic algorithm; and sequential quadratic programming solver are considered as algorithmic agents. We illustrate this approach through a real-world case study of the optimal radioactive waste blending of Hanford site in Southern Washington where nuclear waste is stored.  相似文献   
35.
In this paper, we reflect on the effectiveness of environmental assessment (EA for e.g. projects, policies, plans and programmes) in Iranian water management. Urmia Lake Basin (ULB) is used as a case study area and the extent to which EA appears to be delivering environmental protection objectives is established. Data were collected using document analyses, semi-structured interviews with local experts and site visits. It is established that activities are restricted to project level EIA (environmental impact assessment) and that EA is not able to address and mitigate the negative effects of extensive water exploitation through dam- and well building. Strengthening EIA legislation as well as introducing SEA is suggested as a possible way to address shortcomings, in particular with regard to addressing cumulative and wider basin effects.  相似文献   
36.

Background

Exposure to particulate matter is a risk factor for cardiopulmonary disease but the underlying molecular mechanisms remain poorly understood. In the present study we sought to investigate the cardiopulmonary responses on spontaneously hypertensive rats (SHRs) following inhalation of UfCPs (24 h, 172 μg·m-3), to assess whether compromised animals (SHR) exhibit a different response pattern compared to the previously studied healthy rats (WKY).

Methods

Cardiophysiological response in SHRs was analyzed using radiotelemetry. Blood pressure (BP) and its biomarkers plasma renin-angiotensin system were also assessed. Lung and cardiac mRNA expressions for markers of oxidative stress (hemeoxygenase-1), blood coagulation (tissue factor, plasminogen activator inhibitor-1), and endothelial function (endothelin-1, and endothelin receptors A and B) were analyzed following UfCPs exposure in SHRs. UfCPs-mediated inflammatory responses were assessed from broncho-alveolar-lavage fluid (BALF).

Results

Increased BP and heart rate (HR) by about 5% with a lag of 1–3 days were detected in UfCPs exposed SHRs. Inflammatory markers of BALF, lung (pulmonary) and blood (systemic) were not affected. However, mRNA expression of hemeoxygenase-1, endothelin-1, endothelin receptors A and B, tissue factor, and plasminogen activator inhibitor showed a significant induction (~2.5-fold; p < 0.05) with endothelin 1 being the maximally induced factor (6-fold; p < 0.05) on the third recovery day in the lungs of UfCPs exposed SHRs; while all of these factors – except hemeoxygenase-1 – were not affected in cardiac tissues. Strikingly, the UfCPs-mediated altered BP is paralleled by the induction of renin-angiotensin system in plasma.

Conclusion

Our finding shows that UfCPs exposure at levels which does not induce detectable pulmonary neutrophilic inflammation, triggers distinct effects in the lung and also at the systemic level in compromised SHRs. These effects are characterized by increased activity of plasma renin-angiotensin system and circulating white blood cells together with moderate increases in the BP, HR and decreases in heart rate variability. This systemic effect is associated with pulmonary, but not cardiac, mRNA induction of biomarkers reflective of oxidative stress; activation of vasoconstriction, stimulation of blood coagulation factors, and inhibition of fibrinolysis. Thus, UfCPs may cause cardiovascular and pulmonary impairment, in the absence of detectable pulmonary inflammation, in individuals suffering from preexisting cardiovascular diseases.  相似文献   
37.
Emblicanin rich water‐soluble extract of Emblica officinalis (EEO) is encapsulated in the inner phase of double emulsion (DE) by using emulsifiers in different phases at different concentrations. The effects of other variables like homogenization speed, salt and herbal concentration are also investigated on various phases of DE to obtain a stable matrix. Finally, optimized EEO encapsulated DE has 2% w/w NaCl and 50% w/w EEO in inner (W1) phase, 4% w/w polyglycerol polyricinoleate (PGPR) in middle oil‐phase and 2% w/w low‐methoxy‐pectin and reverse osmosis water in outer (W2) phase. Ultra‐Turrax high shear homogenizer is employed to prepare primary emulsion (W1/O) at 20 000 rpm and DE (W1/O in W2) at 12 000 rpm. The EEO encapsulated DE has been characterized for encapsulation efficiency (>90%), viscosity (0.715 ± 0.18 Pa s), sedimentation stability, zeta potential (?32.17 ±1.17 mV), and particle size. Light and confocal laser microscopy are used for elaborating the microscopic structure of EEO encapsulated DEs. DE has shown storage stability up to 42 days and protect antioxidant activities as compared to control (herbal extract was not encapsulated in the inner phase). The present study demonstrates that the optimized DE matrix can be used to protect the bioactive properties of EEO for its use in functional food formulation.  相似文献   
38.
Sustainable ecosystem management aims to promote the structure and operation of the human components of the system while simultaneously ensuring the persistence of the structures and operation of the natural component. Given the complexity of this task owing to the diverse temporal and spatial scales and multidisciplinary interactions, a systems theory approach based on sound mathematical techniques is essential. Two important aspects of this approach are formulation of sustainability-based objectives and development of the management strategies. Fisher information can be used as the basis of a sustainability hypothesis to formulate relevant mathematical objectives for disparate systems, and optimal control theory provides the means to derive time-dependent management strategies. Partial correlation coefficient analysis is an efficient technique to identify the appropriate control variables for policy development. This paper represents a proof of concept for this approach using a model system that includes an ecosystem, humans, a very rudimentary industrial process, and a very simple agricultural system. Formulation and solution of the control problems help in identifying the effective management options which offer guidelines for policies in real systems. The results also emphasize that management using multiple parameters of different nature can be distinctly effective.  相似文献   
39.
Multimedia Tools and Applications - With over 172 Million people infected with the novel coronavirus (COVID-19) globally and with the numbers increasing exponentially, the dire need of a fast...  相似文献   
40.
Clean Technologies and Environmental Policy - Air pollution exposure assessment involves monitoring of pollutant species concentrations in the atmosphere along with their health impact assessment...  相似文献   
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