Fe/FeO/Fe3O4 composite was synthesized by a simple solid method using ferric citrate and phenolic resin as raw materials. The reaction processes of raw materials mixture were characterized by thermogravimetric analysis (TGA) under nitrogen. X-Ray diffraction (XRD) and scanning electron microscopy (SEM) were used to investigate the structure and morphology of the products. The results showed that the obtained material was octahedral Fe/FeO/Fe3O4 composite with a size of 2-4 mm. The electrochemical performances of Fe/FeO/Fe3O4 composite as anode material were also evaluated, which exhibited a stable specific capacity of 260.3 mAh g-1 and an ideal initial coulombic efficiency of 90.8% in the range of 0.05~3 V at the 5C rate. A good rate capacity of Fe/FeO/Fe3O4 composite electrode was also shown by the charge-discharge testing even at the rate of 60C. The better rate capability of Fe/FeO/Fe3O4 electrode could be measured in higher temperature.

Primary frequency regulation, as an ancillary service, is usually supported by generation reserves. Modern generating units have special technical features; e.g. their governor operation mode can be selected, their ramp rate can be selected to be either normal or fast, etc. On the other hand, there are some technical constraints; e.g. some generating units cannot participate in primary frequency control at their capacity limits. In this paper, operational technical features and constraints of generating units are incorporated in a "simultaneous scheduling of energy and primary reserve" problem. To obtain the optimal scheduling, a heuristic iterative method based on genetic algorithm is proposed. The role of fast ramp rate and other capabilities and constraints on scheduling are investigated through simulation studies. Simulation results show that taking fast ramp rate of generating units into account not only reduces the total operation cost, but will also end up with a feasible solution, even in cases where previously proposed methods fail. Also, simulation results indicate that using fast ramp rate, results in the reduction of both the price of electricity and its volatility.

A new method for baseband demodulation of OQPSK has been proposed in this paper. The sampling rate is two times the Nyquist rate which is very low compared with similar demodulators. The demodulation process includes baseband mixer bank, matching filter, timing recovery and phase recovery. To fasten the process, we have used the fast convolution in matching filter. Besides, a new phase recovery method has been proposed which can be used in other phase demodulators such as QPSK. The high data rate demodulator will demodulate OQPSK with data rates ranging from 1 Mega-bits to more than 500 Mega-bits per second. The experiments show that this architecture can efficiently work with performance loss less than 0. 8dB for low SNR (i. e. Eb/N0≃ 5dB) and 0. 2 dB for high SNR (i. e. Eb/N0≃ 10dB).

Evaluating the cutting rate (CR) of stones is important in the cost estimation and the planning of the stone processing plants. This research used regression models to estimate the stones’ CR based on their physico-mechanical characteristics. Stone processing factories in Mahallat City (Markazi province, Iran) were visited, and the CR of diamond circular saws was recorded on six different travertine stones. Next, the stone block samples were collected from the quarries for laboratory tests. Stones’ porosity (n), uniaxial compressive strength (UCS), and Schmidt hammer hardness (SH) were determined in the laboratory as their physico-mechanical characteristics. Correlation relationships of CR with physico-mechanical characteristics were evaluated using simple and multiple regression analyses, and estimator models were developed. Results showed that multiple regression models are more reliable than simple regression for estimating the stones’ CR. The validity of the developed multiple regression models was verified with the published data of one researcher. The findings indicated that these models are accurate enough for estimating the CR of stones. Consequently, the multiple regression models provide practical advantages for estimating the CR and save time and cost during the planning and design of the stone processing factories.

Background: The current study is to evaluate cardiovascular effects of anesthetic medications and volatile anesthetics on cardiac stress using cardiac stress index (CSI) and rate pressure product (RPP) and to determine which of them in useful in evaluating cardiac stress after comparing results obtained from each method.Materials and methods: 40 patients, 60-80 years old, who were all performed trans abdominal prostatectomy were studied. Patients were divided into two groups, half of patients were placed in group A and the other half in group B. The study was carried out as a blinded study. CSI was measured and evaluated in group A and RPP changes were studied in group B.Results: The mean CSI were 60.25±5.57, 63.05±5.54, 55.75±4.78 and 67.65±4.88 before anesthesia induction, after induction, before surgical incision and in recovery respectively. There was no meaningful difference.RPP mean in four above mentioned stages was 10.15±0.44, 9.9±0.69, 6.8±0.36 and 9.2±0.61 respectively. There was a meaningful difference between RPP in stages before anesthesia induction and before surgical incision (P<0.0001).Conclusion: Considering the obtained results from this study, it can be seen that even in noncardiac surgery, the stress level is high in patients in the stage before surgery. This figure was not clear in RPP index case and was not in accordance with CSI, which means CSI has been able to illustrate existing stress level better and efficiently.

Organizations are increasingly in search of ways to derive more business values from IT investments and the need for IT capabilities (ITC) is surging. ITC is critical significant to build enterprise agility and promote organizational performance. However, IT capability is always treated as the causal factor already existing and there are few studies on how IT capability is created and evaluated. Appropriate evaluation is necessary for an organization to measure, manage and improve enterprise ITC. This research aims to identify and map the dimensions of an organization's ITC. Using a mixed research method, this paper comprises two sections. The qualitative section adopts a systematic literature review (SLR) approach to identify the dimensions of ITC. The quantitative section employs factor analysis to validate identified ITC dimensions and their indicators in an attempt to develop a more precise model for ITC evaluation. The proposed ITC model includes IT management, IT human resources, IT infrastructure, and implementation of IT solutions dimensions as well as the 25 related indicators. Drawing on the results of this paper, organizations can engage in evaluation and improve/create essential ITCs based on the evaluation results.

In this study, theoretical investigations of Li2MSiO4 family cathode materials, including Li2MnSiO4, Li2FeSiO4, Li2CoSiO4, and Li2NiSiO4 are performed using density functional theory (DFT), by GGA and GGA+U methods. The materials properties including electrical conductivity and rate capability were investigated. To evaluate electrical conductivity, we use here a noble approach in DFT established in our previous work, which is related to intrinsic/extrinsic band gap concepts in solid state physics. Also, using lithiated-delithiated junction, aligning Fermi levels, and the difference between conduction bands value is the basis of the comparison of rate-capability, which is also a noble approach. To perform a quantitative investigation of electrical rate-capability, Fermi levels of obtained DOS diagrams of lithiated and delithiated structures were aligned. The difference between maximum of valance band (MVB) of lithiated and delithiated structures was considered as the criteria of rate-capability. The obtained values for the considered materials were fairly close. It was concluded that electron conductivity and rate-capability of this family of Li-ion cathode material is in the same range and do not strictly relate to the transition metal.