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11.
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
12.
Behrouz Sabour Kheirollah Mehrani Azadeh Mehrani Mohammad Hassan Peyrovi 《Journal of Inorganic and Organometallic Polymers and Materials》2013,23(5):1183-1188
MCM-48 nanoporous silica were prepared by the sol–gel method and functionalized by pyridine using a silane agent. With the aid of pyridines on the surface, the nanoporous material was used as a support for immobilization of metalloporphyrin. The formation of this material was confirmed by infrared spectroscopy, X-ray powder diffraction, transmission electron microscopy, inductively coupled plasma atomic emission spectroscopy analysis and specific surface area measurement. The application of this metalloporphyrin-immobilized MCM-48 was investigated as a heterogeneous catalyst in cyclohexene oxidation. Various parameters such as solvent and time were optimized. Also the effect of nanoporous structure on the efficiency of the catalyst was investigated by comparing the results with the same composite using nonporous silica (SiO2). The result showed that the MCM-48 immobilized metalloporphyrin is a better catalyst for cyclohexene oxidation, which can be attributed to its nanoporous structure. The nanoporous structure increases the surface area of MCM-48 and leads to more metalloporphyrin immobilization. 相似文献
13.
Seismic performance evaluation of steel moment resisting frames through incremental dynamic analysis 总被引:2,自引:0,他引:2
Earthquake hazards effect significant damage to structures and cause widespread failure throughout buildings. Moment resisting frames are widely used as lateral resisting systems when sufficient ductility is to be met. Generally three types of moment resisting frames are designed in practice namely Special, Intermediate and Ordinary Moment Frames, each of which has certain level of ductility. Comparative studies on the seismic performance of these three different types of structure are performed in this study. Analytical models of connections are employed including panel zone and beam to column joint model. Incremental dynamic analysis is then utilized to assess the structural dynamic behavior of the frames and to generate required data for performance based evaluations. Maximum annual probability of exceeding different limit states may reveal the superiority of a ductile structure in which a greater behavior factor is employed. Special moment resisting frames are expected to perform better once a certain level of ductility is to be met but the amount of superiority may be the subject of investigation especially from a performance based design standpoint. 相似文献
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Among the high carbohydrate content the cane molasses contains considerable amount of nitrogen compounds including proteins and amino acids. Protein hydrolyzates showed the presence of 16 amino acids with aspartic and glutamic acids and alanine as the major acids in both states bound and free, and there were two unidentified N-containing free acids. Fe, Zn, Mn and Cu were predominant microminerals, K and P were found to be present and in smaller quantities Na. 相似文献
16.
Dipyridamole recognition and controlled release by uniformly sized molecularly imprinted nanospheres
Mehdi Esfandyari-Manesh Mehran Javanbakht Fatemeh Atyabi Ali Mohammadi Somayeh Mohammadi Behrouz Akbari-Adergani Rassoul Dinarvand 《Materials science & engineering. C, Materials for biological applications》2011,31(8):1692-1699
We used novel synthetic conditions of precipitation polymerization to obtain uniformly sized molecularly imprinted nanospheres of dipyridamole for application in the design of new drug delivery systems. In addition, the morphology, drug release, and binding properties of molecularly imprinted polymers (MIPs) were studied, and the effects of morphology on other properties were investigated. The MIPs prepared by acetonitrile/chloroform (19:1, v/v) were uniformly sized nanospheres with an average mean diameter of approximately 88 nm at a wetted state, 50 nm at a dry state, and a polydispersity index of 0.062. The imprinted nanospheres showed excellent binding properties and had 62.7% of template binding compared with 17.1% of its blank polymer. The imprinted nanospheres with 67.5 (mg template/of polymer) of binding capacity had better imprinting efficiency than the 50.5% of binding capacity shown by irregularly shaped MIP particles that were prepared by chloroform. The molecular binding abilities of imprinted nanospheres in human serum were evaluated by HPLC analysis (binding about 77% of dipyridamole). Results from release experiments of MIPs showed a very slow, controlled, and satisfactory release of dipyridamole. The loaded drug was released up to 99% in 17 days for nanospheres and 22 days for irregularly shaped particles. 相似文献
17.
Behrouz Peikari 《Computers & Electrical Engineering》1978,5(4):293-297
This paper considers the problem of designing nonlinear multiport memoryless systems with prescribed driving point and transfer characteristics. It is shown that if the structure of the multiport system is given the input-output characteristics of the nonlinear elements can be obtained iteratively. This is achieved by implementation of a generalized steepest descent criterion. 相似文献
18.
Behrouz BEHNAM Fahimeh SHOJAEI Hamid Reza RONAGH 《Frontiers of Structural and Civil Engineering》2019,13(4):904
Investigating progressive collapse of tall structures under beam removal scenarios after earthquake is a complex subject because the earthquake damage acts as an initial condition for the subsequent scenario. An investigation is performed here on a 10 story steel moment resisting structure designed to meet the life safety level of performance when different beam removal scenarios after earthquake are considered. To this end, the structure is first subjected to the design earthquake simulated by Tabas earthquake acceleration. The beam removal scenarios are then considered at different locations assuming that both ends connections of the beam to columns are simultaneously detached from the columns; thus the removed beam falls on the underneath floor with an impact. This imposes considerable loads to the structure leading to a progressive collapse in all the scenarios considered. The results also show that the upper stories are much more vulnerable under such scenarios than the lower stories. Hence, more attention shall be paid to the beam-to-column connections of the upper stories during the process of design and construction. 相似文献
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Mohammad Taghan Sasanpour Taheri Ali Movafeghi Amir Rokrok Behrouz 《Russian Journal of Nondestructive Testing》2019,55(12):967-974
Russian Journal of Nondestructive Testing - The purpose of this article is to determine the mathematical function of the optical behavior of radiographic films/images produced by gamma-ray... 相似文献