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91.
Collaborative software development involving multiple organizational units, often spanning national, language, and cultural boundaries, raises new challenges and risks that can derail software development projects even when traditional risk factors are being controlled. This article presents a framework that can be used to manage collaborative software development projects, based on an extended set of risk management principles. Three risk factors — trust, culture, and collaborative communication — are discussed in depth. 相似文献
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93.
Faramarzi Marjan Khanmohammadi Hamid Zendehdel Mojgan 《Journal of Porous Materials》2022,29(3):807-815
Journal of Porous Materials - A new molecular anion receptor, HL, was synthesized via condensation reaction of 2-hydroxy-3-methoxy-5-((2,4-dichlorophenyl)diazenyl)benzaldehyde, L, with... 相似文献
94.
Saeed Hesaraki Mojgan Safari Mohammad Ali Shokrgozar 《Journal of materials science. Materials in medicine》2009,20(10):2011-2017
In the present study, bioceramic composites with improved mechanical and biological properties were synthesized by sintering
mixtures of β-tricalcium phosphate and SiO2–CaO–MgO–P2O5 sol–gel derived bioactive glass at 1000–1200°C. The physical, mechanical, structural and biological properties of the composites
were evaluated by appropriate experiments such as microhardness, bending strength, XRD, SEM and MTT. The results showed that
1000 and 1100°C were not appropriate temperatures for sintering the composites and in contrast, the microhardness, bending
strength and bulk density significantly increased by increasing in quantity of bioglass phase when the samples were sintered
at 1200°C. No significant difference was found between the fracture toughness of the composites and pure β-tricalcium phosphate.
β-tricalcium phosphate was structurally stable up to 1200°C and did not transform to its alpha form even in the presence of
the bioglass phase but migration of magnesium cations from the glass composition into its lattice structure was found by right-shift
in XRD patterns, especially when the composite contained higher amount of bioglass component. Calcium silicate was also crystallized
in the composition of the composites, which was more detectable in higher sintering temperatures. The results of the MTT test
showed that proliferation of human osteosarcoma cells on the composites was considerably better than that of pure β-TCP. 相似文献
95.
Farzad Deyhimi Mojgan Sabzehzari Zohreh Karimzadeh 《Chemical Engineering Communications》2007,194(12):1654-1665
The mean activity coefficients for NaCl in a ternary electrolyte system were determined by the potentiometric method, at 25°C, using a solvent polymeric (PVC) sodium-selective membrane electrode (Na+ ISE), containing N,N'-dibenzyl-N,N'-diphenyl-1,2-phenylenedioxydiacetamide as ionophore, and combined with an Ag/AgCl electrode. The potentiometric measurements were performed at the same ionic strengths in different series of mixed salt solutions, each characterized by a fixed salt molal ratio r (where r = m1/m2 = 1, 10, 50, 100). The nonideal behavior of the ternary NaCl(m1) + LiCl(m2) + H2O electrolyte system was described based on the Pitzer ion-interaction model for mixed salts over the ionic strength ranging from 0.01 up to about 4 mol/kg. Two- and three-particle Pitzer interaction parameters for a mixed electrolyte system were determined based on potentiometric data, and the critical role of potentiometric selectivity coefficient (K12) of ISE as limiting factor in the potentiometric measurements was analyzed. 相似文献
96.
Measuring outages in telecommunications switched networks 总被引:2,自引:0,他引:2
The actions taken by end-users, service providers, standards bodies, and government and regulators agencies relating to network reliability and service outages are reviewed. End-to-end customer perceivable characteristics of network reliability and network outages are identified. The traditional definition of reliability is extended to include reliability of a telecommunication network and services. The fundamental concepts of network reliability are formulated. Network outages are defined and a framework for measuring network outages is presented. This framework is applied to the circuit switched network 相似文献
97.
Effect of miscibility on migration of third component in star‐like co‐continuous and disperse‐within‐disperse mixed brushes 下载免费PDF全文
Saleheh Abbaspoor Samira Agbolaghi Mojgan Mahmoudi Yalda Jahanbani Farhang Abbasi Raana Sarvari 《Polymer International》2018,67(1):141-150
Novel ternary mixed‐brush single crystals were designed with disperse‐within‐disperse and star‐like co‐continuous morphologies based on poly(ethylene glycol) (PEG)‐b‐polystyrene (PS)/PEG‐b‐poly(methyl methacrylate) (PMMA)/PEG‐b‐polyaniline (PANI) and PEG‐b‐PS/PEG‐b‐PMMA/PEG‐b‐(poly(?‐caprolactone) (PCL) or poly(l ‐lactide) (PLLA)) block copolymers, respectively. In the disperse‐within‐disperse ternary mixed brushes, PANI nanorods were dispersed within the matrix (PS)–dispersed (PMMA) amorphous brushes. The flexibility and rigidity of brushes mainly affected the ultimate morphology and arrangement of amorphous coiled brushes in the vicinity of PANI nanorods. In addition, the migration of PCL and PLLA crystallizable brushes was evident into PMMA phases dispersed in the PS matrix, leading to star‐like co‐continuous patterns of PCL and PLLA brushes. This phenomenon was related to the miscibility of crystallizable PCL and PLLA brushes with the PMMA phase. The migration of crystallizable PCL and PLLA brushes increased the size of PMMA domains in the star‐like co‐continuous patterns. Despite the larger osmotic pressure of PLLA brushes, their higher miscibility with PMMA chains reflected the greater PMMA dispersal and wider PLLA star‐like branches. © 2017 Society of Chemical Industry 相似文献
98.
Farhang Daneshmand Akbar Karimi Mohammad Reza Nikoo Mohammad Reza Bazargan-Lari Jan Adamowski 《Water Resources Management》2014,28(6):1517-1529
Multi-period optimization of conjunctive water management can utilize reservoirs and aquifer carry-over to alleviate drought impacts. Stakeholders’ socio-economic and environmental indices can be used to minimize the socio-economic and environmental costs associated with water shortages in drought periods. The knowledge gap here is the evaluation and inclusion of the socio-economic and environmental value of conjunctive water management in terms of its drought mitigation capability. In this paper, an integrated water quantity-quality optimization model that considers socio-economic and environmental indices is developed. The model considers and integrates reservoir and aquifer carry-over, river-aquifer interaction and water quality with stakeholders’ socio-economic indices of production, net income and labor force employment to evaluate the socio-economic and environmental value of conjunctive water management. Total dissolved solid (TDS) is used as the water quality index for environmental assessments. The model is formulated as a multi-period nonlinear optimization model, with analysis determining the optimal decisions for reservoir release and withdrawal from the river and aquifer in different months to maximize the socio-economic indices of stakeholders within the environmental constraints. The proposed model is used in Zayandehrood water resource system in Iran, which suffers from water supply and pollution problems. Model analysis results show that conjunctive water use in the Zayandehrood water basin reduces salinity by 50 % in the wetland and keeps water supply reduction during a drought under 10 % of irrigation demand. 相似文献
99.
Chonggang Wang Bo Li Mahmoud Daneshmand Kazem Sohraby Rittwik Jana 《Mobile Networks and Applications》2011,16(1):71-80
Radio frequency identification (RFID) provides a more convenient and automatic approach for object identification than traditional
universal product code-based barcode technology. However, radio communications are naturally unreliable and inevitably lead
to unreliable object identification, which in turn encumber some special applications demanding large-scale deployment of
RFID, even though many RFID applications have been emerging recent years. This paper discusses object identification reliability.
We first list factors that could cause false readings and lead to unreliable object identification. Then we provide five definitions
that directly and formally define object identification reliability. Based on these reliability-related definitions, a general
framework for guaranteeing object identification reliability is proposed in this paper. Existing schemes for reliability improved
are briefly compared within this framework. 相似文献
100.
Mehramizi A Alijani B Pourfarzib M Dorkoosh FA Rafiee -Tehrani M 《Drug development and industrial pharmacy》2007,33(8):812-823
The purpose of this study was to increase the solubility of glipizide (gli) by solid dispersions SDs technique with polyvinylpyrrolidone (PVP) in aqueous media. The gli-PVP solid dispersion systems was prepared by physical mixing or spray drying method, and characterized by differential scanning calorimetry (DSC), X-ray powder diffraction (XRD) analysis, Fourier transformation-infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The elementary osmotic pumps (EOPs) were prepared with gli-PVP complex and the effect of the PVP percentages on the enhancing of gli dissolution rate was studied. The influences of various parameters e.g., drug- PVP ratio, level of solubility modifier, coating weight gain and diameter of drug releasing orifice on drug release profiles were also investigated. The solubility and dissolution rates of gli were significantly increased by solid dispersion using spray dried method as well as their physical mixture. The obtained results indicated that gli-PVP solid dispersion system has suitable solubility behavior in EOP tablets. 相似文献