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排序方式: 共有268条查询结果,搜索用时 15 毫秒
1.
Surfactant-aided gravity drainage is an improved oil recovery technique for water-invaded zone in fractured carbonate reservoirs, which are mostly oil-wet or mixed-wet rocks. The re-infiltration mechanism in water-invaded zone has a considerable effect on oil vertical movement in gravity drainage processes. In this work, a mechanistic understanding of re-infiltration in surfactant-aided gravity drainage, in comparison to oil–water gravity drainage is presented using an experimentally and numerically validated model. A column model is constructed from three matrix blocks. These blocks are separated from each other by horizontal fractures. A storage tank is considered on top of the model to store depleted oil from matrix blocks. The stacked-blocks model for re-infiltration is validated and verified to simulate water and chemical flooding using a mesh independency study and experimental flooding data in a composite core experiment. Using this model, several analyses are performed to investigate effects of rock and fluid properties, rock saturation functions, wettability alteration, surfactant adsorption, and capillary continuity on re-infiltration. 相似文献
2.
A case study validation of a knowledge-based approach for the selection of requirements engineering techniques 总被引:2,自引:1,他引:1
Requirements engineering (RE) is a critical phase in the software engineering process and plays a vital role in ensuring the
overall quality of a software product. Recent research has shown that industry increasingly recognizes the importance of good
RE practices and the use of appropriate RE techniques. However, due to the large number of RE techniques, requirements engineers
find it challenging to select suitable techniques for a particular project. Unfortunately, technique selection based on personal
experience has limitations with regards to the scope, effectiveness and suitability of the RE techniques for the project at
hand. In this paper, a Knowledge-based Approach for the Selection of Requirements Engineering Techniques (KASRET) is proposed
that helps during RE techniques selection. This approach has three major features. First, a library of requirements techniques
was developed which includes detailed knowledge about RE techniques. Second, KASRET integrates advantages of different knowledge
representation schemata and reasoning mechanisms. Thus, KASRET provides mechanisms for the management of knowledge about requirements
techniques and support for RE process development. Third, as a major decision support mechanism, an objective function evaluates
the overall ability and cost of RE techniques, which is helpful for the selection of RE techniques. This paper makes not only
a contribution to RE but also to research and application of knowledge management and decision support in process development.
A case study using an industrial project shows the support of KASRET for RE techniques selection.
相似文献
Behrouz H. FarEmail: |
3.
Erkan Yuce Shahram Minaei Oguzhan Cicekoglu 《Electrical Engineering (Archiv fur Elektrotechnik)》2006,88(6):519-525
In this paper, new floating immittance function simulators employing second-generation current controlled conveyors are proposed.
The first four of the presented circuits employ only a single grounded capacitor as passive component and can realize either
a negative or a positive floating inductor or capacitor. The last two of the proposed circuits do not employ passive components
and can realize either negative or positive floating resistances. All of the proposed circuits do not require passive element
matching. As an application, a third-order butterworth filter is realized using the proposed positive floating inductance
simulator. SPICE simulation results and large signal behavior of the filter are included. 相似文献
4.
Amir Movafeghi Yahaghi Effat Rokrok Behrouz Mirzapour Mahdi 《Russian Journal of Nondestructive Testing》2020,56(4):361-368
Russian Journal of Nondestructive Testing - The location of reinforcement bar in concrete, the bar corrosion, diameter and the depth below the surface are important factors in the evaluation of the... 相似文献
5.
In this paper, a new voltage-mode (VM) first-order phase shifter (all-pass filter) employing only four NMOS transistors and
minimum number of passive elements (i.e. one resistor and one capacitor) is proposed. The proposed VM phase shifter has high
input impedance and does not require passive element matching constraints. Moreover, since only two NMOS transistors are stacked
between positive and negative supply voltages, the proposed circuit is suitable for low-voltage operation. Electronic tunability
can be provided easily by replacing the employed resistor with an NMOS transistor operating in triode region. Simulation results
based on 0.18 μm TSMC CMOS parameters with ±0.9 V supply voltages are given to demonstrate the performance of the proposed
phase shifter. 相似文献
6.
Behrouz Parsa Moghaddam José António Tenreiro Machado 《Journal of scientific computing》2017,71(3):1351-1374
This paper proposes accurate and robust algorithms for approximating variable order fractional derivatives of arbitrary order. The proposed schemes are based on finite difference approximations. We compare the performance of algorithms by introducing a new formulation of experimental convergence order. Two initial value problems are considered and solved by means of the proposed methods. Numerical results are provided justifying the usefulness of the proposed methods. 相似文献
7.
Rouhallah Abedi Firouzjaei Saeid Minaei Babak Beheshti 《Sensing and Instrumentation for Food Quality and Safety》2018,12(3):1513-1518
Non-destructive measurement of qualitative parameters of agricultural produce is quite beneficial in the postharvest operations. The consequential effect of mechanical damage in citrus fruits is rarely visible in their appearance compared to other commodities. The purpose of this study was to propose a fast, non-destructive method for sweet lemon mechanical damage detection using image processing technique and UV radiation. For this purpose, 135 sweet lemons were tested based on a completely randomized factorial design. In order to examine mechanical damage, the independent variables included drop height, fruit diameter and tempering period (holding time at room temperature after treatment). Fruits were dropped from heights of 2, 2.5 and 3 m onto the ground. Then images were captured under UV light having a wavelength of 365 nm, 1, 3 and 6 days after treatment. The images were sent to a PC and analyzed using MATLAB software. “Green Spot Index” or GSI was defined to show the extent of mechanical damage. Results of the analysis of variance showed that the percentage of green spots on fruit skin is significant at the 1% level considering the main and double interaction effects of drop height and fruit diameter. Green spot index significantly increases with the level of mechanical damage. Accuracy of the developed method in differentiating the bruised and undamaged fruits was found to be 100%. 相似文献
8.
Shahram Minaei Oguzhan ÇiÇekoglu Hakan Kuntman Sait TÜrkÖz 《International Journal of Electronics》2013,100(8):915-922
Three new current-mode second-order filter configurations which employ one or two current controlled conveyors (CCCIIs) and three passive elements are presented. Each proposed filter can realize one of the bandpass, lowpass or highpass responses all at high impedance outputs. The proposed filters offer current-control of pole angular frequency ωo without disturbing the parameter ωo /Q. No component matching is required and all the passive and active sensitivities are low. PSPICE simulation results are given to confirm the theoretical analysis. 相似文献
9.
Mohammad Saied Andalib Mehdi Tavakolan Behrouz Gatmiri 《International Journal of Project Management》2018,36(4):600-611
Project valuation, as a decision-making tool for initiating investments in projects, should be able to value project flexibilities and incorporate reasonable risk preferences of relevant decision makers. Real options valuation methods are the available approaches for valuing project flexibilities, whereas they have shortcomings in considering managers’ reasonable risk preferences in project decisions. Therefore, researchers have suggested approximating the perspective on risk of real options methods and practitioners in project management. This study proposes a fair real options valuation for project-based environments by a behavioral economic approach, which adopts binomial lattice method, Monte-Carlo simulation, and cumulative prospect theory. The results show that behavioral factors such as ‘risk attitude’ and ‘loss aversion’ should be accepted in project investment decisions while limited to an acceptable amount depending on the project conditions (e.g. uniqueness of decision-making scenarios). This research contributes to the project management domain by enhancing project investment decisions that include project flexibilities. 相似文献
10.
In this study, we present a new topology for realizing a grounded inductor employing only a single current conveyor, called a negative‐type modified inverting second‐generation current conveyor (MICCII‐), and a minimum number of passive components, two resistors, and one capacitor. The non‐ideality effects of the MICCII‐on a simulated inductor are investigated. To demonstrate the performance of the presented inductance simulator, we use it to construct a third order Butterworth high‐pass filter and a parallel resonant circuit. Simulation results are given to confirm the theoretical analysis. 相似文献