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1.
Measurement of Inlet Drop Size Distribution of Secondary Dispersions by Laser Particle Size Analyzer
Knowledge of the Oil drop size distribution, in addition to the mean drop size, is necessary in order to characterize secondary dispersions. Furthermore, the capture efficiency for any drop flowing through a packed bed depends upon its Oil inlet drop diameter. The Oil/Water secondary dispersions produced by the centrifugal pump were analyzed at regular intervals during an experiment to ascertain the drop size distribution and to check that the feed to the coalescence bed was consistent. New techniques that were developed for measurement of drop size distribution of secondary dispersions using Laser Particle Size Analyzer, which consisted of (He/Ne) laser emitter and laser receiver and lenses. The Laser Particle Size Analyzer was fixed directly to the experimental equipment by using the special designed circular cell. The measurement of drop size distribution was done by computer system with application software package. The new mean drop diameter (i.e., d21) equation has been derived theoretically and the results that predicted from this equation exhibited a maximum error of ±15% from the experimental data. 相似文献
2.
A decision aid for scheduling production in glass fiber manufacturing industry is described. The methodology combines a linear programming (LP) optimization model with a heuristic model. The LP model determines production goals; the heuristic model then uses the LP output to incorporate system-specific constraints in developing processing sequences. 相似文献
3.
Haitham Badi Sabah Hasan Hussein Sameem Abdul Kareem 《Neural computing & applications》2014,25(3-4):733-741
The main objective of this study is to explore the utility of a neural network-based approach in hand gesture recognition. The proposed system presents two recognition algorithms to recognize a set of six specific static hand gestures, namely open, close, cut, paste, maximize, and minimize. The hand gesture image is passed through three stages: preprocessing, feature extraction, and classification. In the first method, the hand contour is used as a feature that treats scaling and translation of problems (in some cases). However, the complex moment algorithm is used to describe the hand gesture and to treat the rotation problem in addition to scaling and translation. The back-propagation learning algorithm is employed in the multilayer neural network classifier. The second method proposed in this article achieves better recognition rate than the first method. 相似文献
4.
Mobile crane manufacturers provide operators and practitioners with tabulated lift-capacity charts. These charts are structured based on predetermined crane configurations, which consist of boom/jib length, lifting radius, lifting height, main boom angles to ground, and jib angle to ground or its offset to its main boom centerline. Practitioners, however, are often required to lift on a partially extended hydraulic section and/or lifting radius other than those listed in the manufacturers’ lift-capacity charts. This paper presents a newly developed optimization algorithm (referred to in this paper as Algorithm-2) for selecting and locating mobile cranes on construction sites based on their minimum boom length and/or minimum radius, accordingly higher lifting capacities. Algorithm-2 includes an optimization procedure that avoids lifting capacity violations. In addition to the practical use of Algorithm 2, the mathematical representations of the crane’s geometry are also useful for research in the automation and robotic field of operations involving cranes. The algorithm is incorporated into a computer system that integrates a selection module and a database. Data pertinent to crane lift configurations are retrieved from the database and are then processed to determine the optimum, geometrical selection of the crane configuration. A case example is described in order to demonstrate the use of the developed algorithm and to illustrate its essential features. 相似文献
5.
Due to the great advances in biomedical digital signal processing, new biometric traits have showed noticeable improvements in authentication systems. Recently, the ElectroCardioGram (ECG) and the PhonoCardioGraph (PCG) have been proposed as novel biometrics. This paper aims to review the previous studies related to the usage of the ECG and PCG signals in human recognition. In addition, we discuss briefly the most important techniques and methodologies used by researchers in the preprocessing, feature extraction and classification of the ECG and PCG signals. At the end, we introduce some future considerations that can be applied in this topic such as: the fusion between different techniques previously used, use both ECG and PCG signals in a multimodal biometric authentication system and building a prototype system for real-time authentication. 相似文献
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Construction projects continue to suffer delays. Things go wrong and the project's completion date gets pushed back, with someone to be blamed for it. In practice, attempts are made to identify the causes of delays and schedules are modified to incorporate revised duration and new project time. The analysis itself is usually complex and can be aided by a computerized approach. This paper discusses different delay analysis techniques that are currently used by practitioners in the construction industry. It also discusses a proposed new delay analysis technique called the Isolated Delay Type (IDT). These techniques were tested against a case example and their strengths and weaknesses highlighted. The new technique can be used as a standalone module for delay analysis or could be incorporated within a computer system for construction delay analysis and claims preparation called Computerized Delay Claims Analysis (CDCA) that integrates different software including an expert system and management software such as scheduling and a database or spreadsheet. 相似文献
9.
Sabah Bouguerra Pierre Letellier Mireille Turmine 《Journal of surfactants and detergents》2010,13(2):217-224
Dodecyldimethyl-amine-N-oxide (DDAO) is a zwitterionic surfactant that can be protonated in water to form DDAOH+ if the pH of the medium is appropriate. We proposed, in a previous study, an experimental approach to determine directly
the ratio of ionization of the surfactant in the micelle and in the bulk, at a given acidity level, without the need of a
presupposed model of protonic exchange. We also showed that the relations of Thermodynamics impose a relationship between
the critical micelle concentration (cmc) and the level of protonation of DDAO in the micelle and in the bulk. In order to
appreciate the general nature of our approach, we have now modified the protonic exchange equilibrium between DDAO and DDAOH+ by introducing butanol into the solution. We studied three mixed media (2, 4 and 6% alcohol by volume). For all these mixtures,
we validated our experimental and theoretical approaches. Moreover, for all the hydroalcoholic mixtures considered and all
pH values, the presence of butanol stabilizes the micelle leading to a decrease of the cmc. Similar to pure water (Lair et
al. in Langmuir, 20:8490–8495, 2004), we showed that, in these media, the protonic exchange equilibrium between DDAOH+ and DDAO in their micellized forms cannot be characterized by an unique equilibrium constant independent of the pH. However,
as the butanol content of the medium increases, the variations in apparent pK with pH decrease, indicating that the behaviour
of the acid–base pair in the micelle is classical and corresponds to a stoichiometric proton exchange. 相似文献
10.
This paper describes a forecasting method for predicting potential cost overruns and schedule delays on construction projects. The output of the forecasting method is useful in evaluating the project status at different time horizons and in quantifying the impact of the performance indicators on the profitability of the job. The method is intended for use by members of project teams in performing integrated time and cost control of construction projects. The paper addresses the effects of a number of factors, referred to in the developed method as indicators, on project cost overruns and schedule delays using fuzzy logic. The proposed forecasting method has been implemented in a prototype that operates in the World Wide Web environment. It has an open architecture that allows users to actively interact and, accordingly, makes use of their own experience and knowledge in the forecasting process. An example project is analyzed to test the developed prototype, demonstrate the use of the proposed method, and to illustrate its capabilities. 相似文献