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21.
When network demands are uncertain, a planner might design a network based on some nominal set of point‐to‐point demands,
and later be faced with a different set of offered demands. To accommodate the offered demands, modification of the network
may be required. Given this scenario, it seems natural to question how these modification costs might affect the overall cost.
To address such questions, we study the effects of random demands on network costs. In this study, we design a network based
on nominal demands, generate random demands based on the nominal demands, and then modify the designed network to carry the
random demands. We generate the offered demands randomly from four different distributions. For each demand distribution we
perform 300 simulations. This paper describes our observations.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
22.
Aazam Nasirian Valliolah Mirkhani Majid Moghadam Shahram Tangestaninejad Iraj Mohammadpoor-Baltork Reza Keshavarzi 《Applied Solar Energy》2016,52(1):32-39
In this work, nanocrystalline P25 TiO2 films with different thicknesses were deposited on FTO coated glass substrates by an electrophoretic deposition technique (EPD) and applied as the work electrode for dye-sensitized solar cells (DSSC) using cis-bis(isothiocyanato)(2,2'-bipyridyl-4,4'-dicarboxylato)(4,4'di-nonyl-2'-bipyridyl) ruthenium(II) (Z907, Dyesol) as sensitizing dye.The results showed that the increasing the thickness of TiO2 films lead to increase the adsorption of the dye on the TiO2 layers which in turns improved the short-circuit photocurrent (Jsc) and open-circuit voltage (Voc), respectively. Furthermore, it was found that the effects of the surface states on the recombination of the photo-injected electrons (electron–hole pairs) in the TiO2 films strongly depend on theTiO2 electrode annealing temperature. Finally, a DSSC with a 32.82 μm thickness for TiO2 film annealed at 600°C produced the highest conversion efficiency with an incident solar energy of 100 mW/cm2 (η = 8.23%, Jsc = 15.98, Voc = 0.73, FF = 0.7). 相似文献
23.
Majid Moghadam Valiollah Mirkhani Shahram Tangestaninejad Iraj Mohammadpoor-Baltork Maedeh Moshref Javadi 《Inorganic chemistry communications》2010,13(2):244-249
The hybrid complex consist of molybdenylacetylacetonate complex covalently linked to a lacunary Keggin-type polyoxometalate, K8[SiW11O39] (POM), was synthesized and characterized by elemental analysis, SEM, XRD, diffuse reflectance UV–Vis and FT-IR spectroscopic methods. The hybrid complex, [MoO2(acac)–POM] (1), was used for alkene epoxidation with tert-BuOOH in 1,2-dichloroethane as solvent. The complex (1) can catalyze epoxidation of various olefins including non-activated terminal olefins. The effect of reaction parameters such as oxidant, solvent, and temperature on the epoxidation of cyclooctene was also investigated. This heterogeneous catalyst was reused several times in the oxidation of cyclooctene. 相似文献
24.
A novel frequency-selective metamaterial with negative permittivity and permeability for improving directivity and gain of a helix antenna is presented in this paper.The proposed metamaterial is composed of two Z-shape resonators printed on opposite sides of a dielectric substrate.Two forms of multilayered cells are found to be suitable for antennas and waveguides applications.In addition,a new method of designing a metamaterial-based helix antenna is presented with high directivity and gain.A comparison on radiation properties is given between the conventional and the new metamaterial-based helix antennas.Two comparisons on radiation properties are performed:(1) the effect of proposed Z-structure on monopole,dipole,and helix antennas;(2) the effect of OE3,split-ring resonator (SRR),and proposed Z-structure unit cells on the performance of helix antennas.The results show improvement of parameters such as directivity,gain,and radiation power of the new metamaterial-based helix antenna.Therefore,the combination of Z-structure with the helix antenna shows the best performance. 相似文献
25.
26.
This paper presents the details of a computationally efficient automatic voltage contingency selection algorithm developed for implementation at the AEP's new system control center in Columbus, Ohio. The methodology is based on the quantification of the real-time system-wide impacts of the transmission branch (line and transformer) outages on the load bus voltage profile via the fast computation of a quadratic system Performance Index (PI) for every branch, and subsequent sorting of the results according to the severity of effects. The algotithm enjoys superior computational complexity compared to the previously published work. An application of the algorithm to the AEP EHV real-time data base is presented as an illustration. 相似文献
27.
Gholamreza Hosseinyar Reza Moussavi-Harami Iraj Abdollahie Far Asadollah Mahboubi Rooholah Noemani Rad 《石油科学(英文版)》2019,16(4):776-793
Lower Cretaceous Shurijeh–Shatlyk Formations host some of the main reservoirs in the Kopeh Dagh-Amu Darya Basin.Exploration in this area so far has focused on the development of structural traps, but recognition of stratigraphic traps in this area is of increasing importance. Integration of 3D seismic data with borehole data from thirteen wells and five outcrop sections was used to identify potential reservoir intervals and survey the hydrocarbon trap types in the East Kopeh Dagh Foldbelt(NE Iran). Analyses of horizontal slices indicated that the lower Shurijeh was deposited in a braided fluvial system.Generally, three types of channel were identified in the lower Shurijeh Formation: type 1, which is low-sinuosity channels interpreted to be filled with non-reservoir fine-grained facies; type 2, which is a moderately sinuous sand-filled channel with good prospectively; and type 3, which is narrow, high sinuosity channel filled with fine-grained sediments. Results indicate that upper Shurijeh–Shatlyk Formations were deposited in fluvial to delta and shallow marine environments. The identified delta forms the second reservoir zone in the Khangiran Field. Study of the stratigraphic aspects of the Shurijeh succession indicates that both lower and upper Shurijeh reservoirs are stratigraphic reservoir traps that improved during folding. 相似文献
28.
Sivakumar P. Nagaraju Regonda Samanta Debabrata Sivaram M. Hindia Mhd. Nour Amiri Iraj Sadegh 《Wireless Networks》2020,26(4):2317-2328
Wireless Networks - Nowadays, the smart grid has demonstrated a great ability to make life easier and more comfortable given recent advances. This paper studies the above issue from the perspective... 相似文献
29.
30.
R. Udaiyakumar Senoj Joseph T. V. P. Sundararajan D. Vigneswaran R. Maheswar Iraj S. Amiri 《Wireless Personal Communications》2018,103(1):99-115
The aggressive scaling of CMOS technology has inevitably led to vastly increased power dissipation, process variability and reliability degradation, posing tremendous challenges to robust circuit design. To continue the success of integrated circuits, advanced design research must start in parallel with or even ahead of technology development. In this paper, an attempt is made to analyze various circuits’ delay and power performance by introducing certain level of variation to important process parameters like threshold voltage (Vth), mobility of carriers (μ0), oxide thickness (tox) and doping concentration (nsd). Basic Monte Carlo simulation is carried out on these circuits to ascertain the stability in performances. A 16 × 1 multiplexer is considered for detailed analysis. SPICE characterization is done for three different input slew rates (0.1, 0.5 and 1 ns) against four different output load drive strengths (1×, 2×, 3× and 4× output capacitive load). From the obtained results, output slew rates and average power results are observed and discussed. 相似文献