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1.
The research literature has seen a number of studies aimed at understanding customer attitudes towards banking technologies, and thereby providing implications for developmental planning and marketing. However, even though banking technologies have a significant amount of information systems (IS) component to them, there is a paucity of research that considers them from the IS perspective. In this paper, we fill this gap by considering three constructs, namely usefulness, ease of use and usage, that are all rooted in the IS literature. We study user’s perceptions of these constructs, as well as the relationships among them, for both online and telephone banking.  相似文献   
2.
Motivated by the possibility of modifying energy levels of a molecule without substantially changing its band gap, the impact of gradual fluorination on the optical and structural properties of zinc phthalocyanine (FnZnPc) thin films and the electronic characteristics of FnZnPc/C60 (n = 0, 4, 8, 16) bilayer cells is investigated. UV–vis measurements reveal similar Q‐ and B‐band absorption of FnZnPc thin films with n = 0, 4, 8, whereas for F16ZnPc a different absorption pattern is detected. A correlation between structure and electronic transport is deduced. For F4ZnPc/C60 cells, the enhanced long range order supports fill factors of 55% and an increase of the short circuit current density by 18%, compared to ZnPc/C60. As a parameter being sensitive to the organic/organic interface energetics, the open circuit voltage is analyzed. An enhancement of this quantity by 27% and 50% is detected for F4ZnPc‐ and F8ZnPc‐based devices, respectively, and is attributed to an increase of the quasi‐Fermi level splitting at the donor/acceptor interface. In contrast, for F16ZnPc/C60 a decrease of the open circuit voltage is observed. Complementary photoelectron spectroscopy, external quantum efficiency, and photoluminescence measurements reveal a different working principle, which is ascribed to the particular energy level alignment at the interface of the photoactive materials.  相似文献   
3.
In this research, we utilise a multi-method braided approach for a real-world health care intervention in rural India. We first use action research to conceptually underpin the role of self-help groups, disease profiles and appropriate interventions in health care behaviour change and improvement. Action research is then coupled with a non-linear integer-programming-based simulation to determine how health care resources need to be distributed over time, disease type and groups. The action research provides specific research questions and distributional forms needed for the optimisation analysis, while the non-linear integer-programming simulation provides specific recommendations on where and when to distribute resources. External validity of the study is ensured by the adoption of recommendations in the field as part of the action research. Findings from this research have important policy implications. For example, it identifies the value of continuous embedded interventions as opposed to periodic ones and the importance of flexibility in terms of which community groups and disease types to serve over time. This research also provides an important bridge between the operations research, health care in developing nations, organisational theory and humanitarian operations bodies of knowledge.  相似文献   
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5.
Experimental studies were performed to investigate the role and influence of grain movement on macrosegregation and microstructure evolution during equiaxed solidification. Casting experiments were performed with a grain-refined Al-Cu alloy in a rectangular sand mold. For the aluminum alloy studied, the equiaxed grains are lighter than the bulk melt and thus float up. Experiments were designed to investigate floatation phenomena of equiaxed grains in the presence of thermosolutal convection. Cooling curves were recorded at key locations in both the casting and the chill. Quantitative image analysis and spatial chemical analysis were performed on the solidified casting to observe the chemical and microstructural inhomogeneity created by the melt convection and solid floatation. Several notable features that can be attributed to grain movement were observed in temperature histories, macrosegregation patterns, and microstructures. In our experiments, the floatation of grains influences the thermal conditions and the overall flow direction in the casting cavity. In some cases, the induced flow resulting from the grain movement caused a flow reversal. This in turn influences the solidification direction, microstructure evolution, and the overall macrosegregation behavior.  相似文献   
6.
Despite the possibility of short-term financial losses and concerns by executive management of potential failure, enterprise information technologies (EITs) are being implemented by a growing number of Fortune 100 and midsize corporations in the hope of acquiring long-term benefits. EITs, expensive and risky information technology assets, must be evaluated on the basis of both their productivity gains and their support for corporate reengineering through integration of business processes. In this paper, we propose a two-stage methodology (involving a combination of the analytical network process and integer programming) to conduct a high-level evaluation of an interdependent set of tangible, intangible, strategic and operational factors that should be considered in EIT evaluation. We perform sensitivity analyses and conduct tests with real-world data to show the robustness of our methodology and the resulting managerial implications.  相似文献   
7.
Journal of Materials Science - Atomic arrangements in the nanostructured grains and interfaces of thermally evaporated Au/Cu multilayer thin films on polycrystalline Si substrate have been explored...  相似文献   
8.
ABSTRACT

In this study, COMSOL multi-physics modelling software was used to make a computational model of a bare helical tube cross flow heat exchanger in order to simulate the temperature changes in the heat exchanger. The computational results of heat transfer are validated by using the analytical models. A conjugate convection/conduction heat transfer model was developed, which exhibited good agreement to the experiments. A different velocity of air taken into the consideration to find out the temperature distribution through the pipe and air temperature inside the duct. The temperature profile, and the overall heat transfer rate from the wall of the tube were calculated and plotted for theoretical, experimental and Numerical method using the k- conjugate heat transfer model. The model is validated through comparison with theoretical relations for single-pass cross-flow arrangements and with experimental results also. Simulation results showed good agreement with experimental values with respect to different mass flow rates.  相似文献   
9.
A stochastic numerical approach was developed to model the formation of grain structure and secondary phases during the solidification of nickel-based alloy 718 remelt ingots. The significance of the present stochastic approach is that the simulated phases can be directly compared with actual phases from experiments at two different scales: grain characteristics can be visualized at the macroscale, while the amount, size, and distribution of secondary phases can be viewed at the microscale. The computer becomes a “dynamic metallographic microscope.” Stochastic modeling was applied to simulate the formation of solidification phases (γprimary phase and NbC and eutectic γ-Laves secondary phases) during the solidification of vacuum-arc-remelted and electroslag-remelted alloy 718 ingots. Modeling results, such as pool profile, grain-growth pattern, grain structure (both columnar and equiaxed grains), columnar-to-equiaxed transition, grain size, and secondary dendrite arm spacing, as well as amount, size, and location of both eutectic γ-Laves and NbC phases compared well with experimental data for cast alloy 718. This research demonstrates that the stochastic approaches are relatively fast, comprehensive, and more accurate than the deterministic approaches in predicting the solidification characteristics of remelt ingots and are mature enough to be used effectively by the metal industry for process development and optimization. Laurentiu Nastac earned his Ph.D. in metallurgical and materials engineering at the University of Alabama at Tuscaloosa in 1995. He is currently a senior staff engineer at Concurrent Technologies Corporation. Dr. Nastac is a member of TMS. Suresh Sundarraj earned his Ph.D. in mineral engineering at the University of Minnesota in 1994. He is currently a process modeling engineer for Concurrent Technologies Corporation. Dr. Sundarraj is also a member of TMS. Kuang-O Yu earned his Ph.D. in metallurgical engineering at the University of Kentucky in 1978. He is currently director of research and development at RMI Titanium Company. Dr. Yu is also a member of TMS. Yuan Pang earned his M.S. in mechanical engineering at the University of Akron in 1977. He is currently a principal engineer at Concurrent Technologies Corporation.  相似文献   
10.
In this paper, a theoretical model is developed to investigate the performance of the hybrid solar thermoelectric generator (HSTEG) system, which is designed without (B-HSTEG) and with an evacuated glass tube (V-HSTEG). The heat loss, power output, thermal efficiency, and electrical efficiency of the B-HSTEG/V-HSTEG system are evaluated by analyzing the design parameters such as geometric solar concentration ratio, thermoelectric figure of merit, and cold-side inlet fluid temperature. The performance of the B-HSTEG is compared with the V-HSTEG system using two heat transfer fluids: water and Therminol VP-1. The maximum electrical efficiency of the B-HSTEG and V-HSTEG is estimated to be 12.2 and 15.6% (ZT = 3) with a corresponding thermal efficiency of about 61.9 and 60.3%, respectively. Overall, this paper provides a systematic performance analysis of HSTEG systems.  相似文献   
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