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1.
With the ongoing challenge of successfully managing information technology (IT) projects, organizations are recognizing the need for greater project management discipline. For many organizations, this has meant ratcheting up project management skills, processes, and governance structures by implementing a project management office (PMO). While anecdotal evidence suggests that implementing a PMO can be quite difficult, few studies discuss the specific challenges involved, and how organizations can overcome them. To address this gap in existing knowledge, we conducted a Delphi study to (1) identify the challenges of implementing a PMO for managing IT projects, (2) rank these challenges in order of importance, (3) discover ways in which some organizations have overcome the top-ranked challenges, and (4) understand the role of PMO structure, metrics, and tools in the implementation of a PMO.We identified 34 unique challenges to implementing a PMO and refined this list to 13 challenges that our Delphi panelists considered most important. The top-three challenges were (1) rigid corporate culture and failure to manage organizational resistance to change, (2) lack of experienced project managers (PMs) and PMO leadership, and (3) lack of appropriate change management strategy. Through follow-up interviews with selected panelists, we identified a series of actions that can be taken to overcome these challenges including having a strong PMO champion, starting small and demonstrating the value of the PMO, obtaining support from opinion leaders, hiring an experienced program manager who understands the organization, bringing the most talented PMs into the PMO implementation team, adopting a flexible change management strategy, and standardizing processes prior to PMO implementation. The interviews were also used to better understand the role of PMO structure, metrics, and tools. In terms of PMO structure, we found that ‘light’ PMOs were more likely to be implemented successfully. Most organizations eschew formal metrics, instead relying on subjective indicators of PMO success. Lastly, it appears that PMO tools are difficult to implement unless a project management culture has been established. 相似文献
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Substituted polyaniline, poly(N-ethyl aniline) (PNEA), doped with camphor sulphonic acid (CSA) and p-toluene sulphonic acid (p-TSA), was synthesized by single-step chemical polymerization method using ammonium persulphate as an oxidizing agent. This is a single-step polymerization process to synthesize directly the conducting emeraldine salt phase of the polymer using CSA and p-toluene sulphonic acid as dopants. The synthesized polymers were characterized by UV–vis and FTIR spectroscopy, scanning electron microscopy, TGA/SDTA, DSC, and conductivity measurements. This single-step chemical synthesis method offers a polymer having very good physicochemical properties with good electrical conductivity. High temperature conductivity measurements show “thermal activated behavior.” The change in resistance with respect to % relative humidity (% RH) is observed, when pressed pellets of the polymer were exposed to the broad range of humidity (ranging between 20 and 100% RH). POLYM. ENG. SCI., 47:1621–1629, 2007. © 2007 Society of Plastics Engineers 相似文献
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Narayana Thota M. Gurubhaskar A. C. Kasi Reddy G. Hema Chandra B. R. Mehta Ashutosh Tiwari Y. P. Venkata Subbaiah 《Journal of Materials Science: Materials in Electronics》2017,28(16):11702-11711
In this paper, we report the two stage growth of Cu2ZnSnS4 (CZTS) thin films as a function of sulfurization time. First, magnetron sputtered metallic precursors were deposited sequentially (Zn/Cu/Sn/Cu) over rotating glass substrates held at 230?°C. Later, the sputtered precursors were heat treated at 500?°C in the ambiance of sulfur for various time durations in the range, 10–120 min. The sulfur treated samples were examined using various analytical tools to understand the role of sulfurization time on the CZTS growth and properties. From composition and structural analysis, Zn/Cu/Sn/Cu precursors sulfurized for shorter duration (10 and 20 min) revealed severe deficiency of sulfur that resulted in several metallic, bi-metallic and metal sulfide phases. With the increase of sulfurization time to 30 min, sulfur incorporation was enhanced and reached stoichiometric ratio (~50% S) for CZTS growth, however, samples were poorly crystalline in nature and consisted of prominent Cu2?xS phase as well. The Zn/Cu/Sn/Cu precursors sulfurized for 60 min exhibited prominent CZTS phase without Cu2?xS phase. Further, rise in sulfurization time to 120 min enabled drastic improvement in crystallinity of CZTS phase. Raman mapping over 60 µm × 60 µm for these films confirmed the homogeneous phase growth of CZTS. XPS study revealed the oxidation states of Cu1+, Zn2+, Sn4+ and S2? in CZTS films. The optimized films showed high absorption coefficient of 105 cm?1 with an optical band gap of 1.51 eV. These films showed leaf like grain morphology with high mobility and low resistivity of 18.2 cm2/V-s and 0.7 Ω-cm, respectively. 相似文献
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A novel synthetic protocol for the one‐pot chemo‐ and stereoselective construction of diversely functionalized pyrido[1,2‐a]pyrimidin‐4‐imines via copper(I)‐catalyzed [3+2] cycloaddition/ring‐opening rearrangement/[4+2] cycloaddition/aromatization cascade of sulfonyl azides, alkynes and N‐arylidenepyridin‐2‐amines under mild reaction conditions is reported. In addition, the catalytic activity of copper(I)‐modified zeolite, a recyclable, heterogeneous catalyst is also investigated, which gives improved yield compared to its homogeneous equivalents. 相似文献
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The effect of cutting speed, tool rake angle, and wearland length on the nature of the surface generated in machining annealed red brass under unlubricated and lubricated conditions is studied. The machined surfaces are examined using optical and scanning electron microscopy. The machined surfaces were observed to have defects such as microcracks and macrocracks perpendicular to the direction of relative work-tool motion, cavities and plastically deformed regions. The surface damage decreases with an increase in the cutting speed and/or the positive tool rake angle. The presence of lubricant in the cutting region results in a surface of high quality. 相似文献
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Diamondlike films have unique properties that can be tailored between those of diamond and those of graphite to meet industrial applications. The purpose of this review is to emphasize the ability to prepare films with specific properties through control of the deposition parameters. The three basic approaches, plasma deposition, chemical vapor deposition, and ion beam deposition, are presented. Since the first two methods consist of complex chemical-physical systems which limit the possibilities for controlled parametric studies, the focus herein is on the latter technique. This work presents the unique capabilities of mass-selected carbon ion beam deposition in controlling deposition parameters over a wide range, particularly when combined with in-situ analysis of film evolution. The role of different deposition parameters on diamond film growth is discussed. The Houston deposition system that manifests the above features is described. A summary of results of some ongoing experiments is given to demonstrate the system capabilities for both parametric studies of diamondlike film growth and actual production of diamondlike films. 相似文献
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Milind V. Kulkarni Annamraju Kasi Viswanath R. Marimuthu U. P. Mulik 《Journal of Materials Science: Materials in Electronics》2004,15(12):781-785
Conducting polymer, Poly(o-toluidine) was synthesized by chemical oxidative polymerization method using different inorganic acids such as HCl, H2SO4, HClO4, HNO3, H3PO4 and H3BO3 as protonic acid media. Synthesized polymers were characterized by UV-Visible and FT-IR spectroscopy. Conducting emeraldine salt phase of the polymer has been confirmed with the help of spectroscopic analysis. Thermal stability of these polymers were investigated by thermogravimetric (TG/SDTA) analysis. Increase in conductivity with increase in temperature was observed in all the samples. 相似文献