732 research outputs found
Identification and classification of shareable tacit knowledge associated with experience in the Chinese software industry sector
The study reported in this thesis aimed to provide an ontology of professional activities in the software industry that require and enable the acquisition of experience and that, in turn, is the basis for tacit knowledge creation. The rationale behind the creation of such an ontology was based on the need to externalise this tacit knowledge and then record such externalisations so that these can be shared and disseminated across organisations through electronic records management. The research problem here is to conciliate highly theoretical principles associated with tacit knowledge and the ill-defined and quasi-colloquial concept of experience into a tool that can be used by more technical and explicit knowledge minded practitioners of electronic records management.
The ontology produced and proposed here provides exactly such a bridge, by identifying what aspects of professional and personal experience should be captured and organising these aspects into an explicit classification that can be used to capture the tacit knowledge and codify it into explicit knowledge. Since such ontologies are always closely related to actual contexts of practice, the researcher decided to choose her own national context of China, where she had worked before and had good guarantees of industrial access.
This study used a multiple case-study Straussian Grounded Theory inductive approach. Data collection was conducted through semi-structured interviews in order to get direct interaction with practitioners in the field and capture individuals opinions and perceptions, as well as interpret individuals understandings associated with these processes. The interviews were conducted in three different and representative types of company (SMEs, State Owned and Large Private) in an attempt to capture a rich variety of possible contexts in the SW sector in a Chinese context. Data analysis was conducted according to coding the procedures advocated by Grounded Theory, namely: open, axial and selective coding. Data collection and analysis was conducted until the emergent theory reached theoretical saturation.
The theory generated identified 218 different codes out of 797 representative quotations. These codes were grouped and organised into a category hierarchy that includes 6 main categories and 31 sub-categories, which are, in turn, represented in the ontology proposed. This emergent theory indicates in a very concise manner that experienced SW development practitioners in China should be able to understand the nature and value of experience in the SW industry, effectively communicate with other stake holders in the SW development process, be able and motivated to actively engage with continuous professional development, be able to share knowledge with peers and the profession at large, effectively work on projects and exhibit a sound professional attitude both internally to their own company and externally to customers, partners and even competitors.
This basic theory was then further analysed by applying selective coding. This resulted in a main theory centred on Working in Projects, which was clearly identified as the core activity in the SW Industry reflecting its design and development nature. Directly related with the core category, three other significant categories were identified as enablers: Communication, Knowledge Sharing and Individual Development. Additionally, Understanding the Nature of Experience in the SW Industry and Professional Attitude were identified as drivers for the entire process of reflection, experience acquisition and tacit knowledge construction by the individual practitioners.
Finally, as an integral part of any inductive process of research, the final stage in this study was to position the emerged theory in the body of knowledge. This resulted in the understanding that the theory presented in this study bridges two extremely large bodies of literature: employability skills and competencies. Both of these bodies of literature put their emphasis in explicit knowledge concerning skills and competencies that are defined so that they can be measured and assessed. The focus of the theory proposed in this thesis on experience and resulting acquisition of tacit knowledge allows a natural link between the employability skills and competencies in the SW industry that was hitherto lacking in the body of knowledge.
The ontology proposed is of interest to academics in the areas of knowledge management, electronic records management and information systems. The same ontology may be of interest to human resources practitioners to select and develop experienced personnel as well as knowledge and information professionals in organisations
Identification of tacit knowledge associated with experience: a Chinese software industry study
This paper reports on a research project that aimed at identifying the professional and personal experience from
individuals in the SMEs in the Software (SW) industry sector in China. This study employed an inductive qualitative
approach based on a single case study and grounded theory (GT) data analysis. The SW company is a SME that specialises
in multimedia SW research and development and is located in Xiamen City (Fujian Province, South of China). Six
participants, selected on the basis of their role in SW design and development, were interviewed using a semiāstructured
interview script. These inādepth interviews ranged from 100 to 120 minutes in length. After completing the open coding of
the six interview transcripts, the researcher obtained 121 codes and 215 quotations from the interview data. These codes
were grouped and organized into a category hierarchy that included 6 main structured categories as the result of axial
coding. The results of the study enabled the development of a taxonomy and classification of tacit knowledge related to
experience in the different stages of the SW development process. The study also showed that each identified category of
tacit knowledge is not necessarily confined to one specific SW development stage or even to a specific role in the process.
This emergent theory challenges traditional perceptions that each stage requires very precise types of skills, experience
and even types of individuals
Plasmons in Pb nanowire arrays on Si(557): Between one and two dimensions
The plasmon dispersion in arrays of nanowires of Pb close to an average Pb coverage of one monolayer was determined on the Si(557) surface using electron energy loss spectroscopy with both high energy and momentum resolution. While we find purely one-dimensional (1D) plasmon losses at a Pb concentration of 1.31 monolayers (ML), measured with respect to the Si(111) surface concentration, the 1.2 and 1.4 ML coverages exhibit wavelength-dependent transitions from 1D to anisotropic 2D properties. However, due to the high anisotropy in the system at all coverages, the dispersion curves exhibit 1D characteristics in both directions. This behavior seems to be related to the Pb-induced refacetting of the Si(557) surface, which depends on Pb coverage. It changes both effective system sizes and coupling strength between miniterraces. Ā© 2011 American Physical Society.Ministry of Education, Culture, Sports, Science, and Technology, Japa
Wider. Bigger. Greater. Neo-Palladian country houses as representations of power struggle, globalization and "Britishness" in the United Kingdom of the 1750s
Neo-Palladianism in the United Kingdom followed a clear formula when it was first introduced in the 1720s: small and compact villas, a central portico and references to the Villa Emo or La Rotonda. This concept changed significantly till the 1750s: wings were added, the complexes became wider and references became more diverse. The early 18th century was also a time of change for the political and social situation in the United Kingdom. The Hanoverians took over the throne from the Stuarts in 1714 and the Whigs governed the country for almost three decades. At the same time the world had become more global thanks to colonization and Britain was constantly in conflict with continental Europe. This meant that the collective identity of the British elite had to be newly created. This thesis discusses how Neo-Palladian country houses on the English countryside were used to create this new collective identity of the British elite in the 1750s
Substrate-Dependent Two-State Reactivity in Iron-Catalyzed Alkene [2+2] Cycloaddition Reactions
Iron-catalyzed alkene
[2+2] cycloaddition reactions represent a
promising stepwise pathway to effect the kinetically hindered concerted
[2+2] cycloaddition. However, the fundamental reactivity paradigm
of these reactions remains unclear. Based on high level combined CASPT2/DFT
modelings, herein we reveal an unprecedented substrate-dependent two-state
reactivity scenario for the key CīøC coupling in this iron catalysis,
in which the representative substrates of mono-olefins only and mono-olefin
plus 1,3-diene exhibit different reactivity paradigms. The role of
the redox-active ligand is found to generate a ferric oxidation state
for the metallacyclic intermediate of CīøC coupling, thereby
rendering a thermodynamically more accessible Fe<sup>III</sup>/Fe<sup>I</sup> reductive elimination process compared with the otherwise
Fe<sup>II</sup>/Fe<sup>0</sup> one. The enhancement of the spin state
transition efficiency between the singlet and triplet states is predicted
as an alternative way to increase the CīøC coupling reactivity
in the cross [2+2] cycloaddition reactions between mono-olefins and
dienes. This work highlights the ab initio multi-reference method
in describing very complicated open-shell iron catalysis
Mechanism of Organophosphonate Catabolism by Diiron Oxygenase PhnZ: A Third Iron-Mediated OāO Activation Scenario in Nature
Diiron
oxygenase PhnZ catalyzes the catabolism of organophosphonate
(Pn) (<i>R</i>)-2-amino-1-hydroxyethylphosphonic to glycine
and inorganic phosphate (Pi). In this Pn catabolism way, PhnZ oxidatively
cleaves the highly stable CāP bond in Pn to produce Pi. However,
the mechanism of this enzyme that affords aquatic and marine bacteria
in Pi-limited environments to utilize the most abundant environmental
Pn (2-amino-ethylphosphonic acid) as the source of Pi is still unclear.
In this work, extensive QM/MM calculations reveal that the mechanism
of PhnZ consists of four consecutive steps: (1) rate-limiting Ī±-H
abstraction of Pn by Fe<sup>III</sup>-superoxo; (2) formation of Fe<sup>III</sup>OOC<sub>Ī±</sub> peroxide; (3) concerted O insertion
into C<sub>Ī±</sub>āP bond of Pn initiated by āinverseā
heterolytic OāO cleavage; and (4) phosphate hydrolysis to glycine
and Pi. Intriguingly, the enzymatic reaction mechanism of PhnZ for
the crucial breakage of the CāP bond is characterized by the
āinverseā heterolytic OāO cleavage of Fe<sup>III</sup>OOC<sub>Ī±</sub> intermediate, which renders the distal
O atom more oxidative to oxygenate Pn than the homolytic OāO
cleavage. In this way, PhnZ adopts a mechanism quite different from
the related diiron oxygenase MIOX, with His62 residue playing an important
role. This unusual āinverseā heterolytic OāO
cleavage mode, apart from the well-known homolytic and ānormalā
heterolytic ones, constitutes a third iron-mediated OāO activation
scenario in nature, which is expected to have its broad occurrence
in oxidative transformation involving heteroatoms of sulfur and phosphorus
Convergent Theoretical Prediction of Reactive Oxidant Structures in Diiron Arylamine Oxygenases AurF and CmlI: Peroxo or Hydroperoxo?
AurF and CmlI are
currently the only two known diiron arylamine
oxygenases. On the basis of extensive quantum mechanical/molecular
mechanical (QM/MM) spectroscopic and mechanistic modelings, here we
predict that the key oxygenated intermediates in AurF and CmlI, so-called <b>P</b>, are uniformly hydroperoxo species having similar structures.
As a basis for mechanistic unification in AurF and CmlI, the proposed
diferric-hydroperoxo <b>P</b> is calculated to be able to promote
the arylamine N-oxygenation with highly accessible kinetics. This
convergent Ī¼-Ī·<sup>0</sup>:Ī·<sup>2</sup> structural
assignment of <b>P</b>ās in AurF and CmlI can rationalize
many conundrums for <b>P</b>, including the different MoĢssbauer
spectroscopic parameters, low OāO vibrational frequency, ambiphilic
reactivity, and inertness toward CāH activation. In view of
the very limited knowledge about hydroperoxo species in diiron enzymes,
the novel diferric-hydroperoxo-mediated N-oxygenation mechanism revealed
in this work opens up a new avenue for understanding the O<sub>2</sub> activation mode in nature. For elucidating the structures of transient
oxidants for diiron enzymes, the promising approach of QM/MM MoĢssbauer
spectroscopic modeling is highlighted as a key problem solver in mechanistic
enzymatic research
Performance of Density Functionals for Activation Energies of Re-Catalyzed Organic Reactions
By employing high-level coupled cluster
CCSDĀ(T)-F12 calculations
as reference, we herein systematically assessed the performance of
16 popular density functional theory (DFT) approximations for typical
rhenium-catalyzed reactions. The reactions under study cover those
catalyzed by low-valent rheniumĀ(I)/(III) carbonyl complexes as well
as high-valent organorheniumĀ(VII) bisperoxo complex. Without DFT dispersion
correction, the four best-performing functionals for the barrier heights
are B2GP-PLYP, TPSSh, B3LYP, and PBE0 with the mean unsigned deviations
(MUDs) under 1.6 kcal/mol. Among these four functionals, B2GP-PLYP
generates more accurate barrier heights, while B3LYP and TPSSh behave
more reliably in the barrier trend description for these Re-catalyzed
reactions. In general, herein the hybrid functionals are better choices
than pure GGA or pure meta-GGA functionals. DFT empirical dispersion
corrections were found to have beneficial effects on MUDs only for
four tested functionals of BMK, CAM-B3LYP, LC-ĻPBE, and ĻB97X.
Often associated with very large errors up to about 15 kcal/mol in
barrier height for many tested functionals, the reaction catalyzed
by high-valent rheniumĀ(VII) bisperoxo is apparently different from
the ones catalyzed by low-valent rheniumĀ(I)/(III) carbonyl complexes.
For reactions catalyzed by ReĀ(I)/(III) carbonyl complexes, ĻB97XD
with dispersion correction performs excellently (MUD = 0.63 kcal/mol)
and hence is highly recommended for these ReĀ(I)/ReĀ(III)-mediated reactions
Assessment of DFT Methods for Computing Activation Energies of Mo/W-Mediated Reactions
Using high level ab initio coupled
cluster calculations as reference,
the performances of 15 commonly used density functionals (DFs) on
activation energy calculations for typical Mo/W-mediated reactions
have been systematically assessed for the first time in this work.
The selected representative Mo/W-mediated reactions cover a wide range
from enzymatic reactions to organometallic reactions, which include
Mo-catalyzed aldehyde oxidation (aldehyde oxidoreductase), Mo-catalyzed
dimethyl sulfoxide (DMSO) reduction (DMSO reductase), W-catalyzed
acetylene hydration (acetylene hydratase), Mo/W-mediated olefin
metathesis, Mo/W-mediated olefin epoxidation, W-mediated alkyne metathesis,
and W-mediated CāH bond activation. Covering both Mo- and W-mediated
reactions, four DFs of B2GP-PLYP, M06, B2-PLYP, and B3LYP are uniformly
recommended with and without DFT empirical dispersion correction.
Among these four DFs, B3LYP is notably improved in performance by
DFT empirical dispersion correction. In addition to the absolute value
of calculation error, if the trend of DFT results is also a consideration,
B2GP-PLYP, B2-PLYP, and M06 keep better performance than other functionals
tested and constitute our final recommendation of DFs for both Mo-
and W-mediated reactions
Performance of Density Functionals for Activation Energies of Zr-Mediated Reactions
Coupled cluster CCSDĀ(T) calculations
with coreāvalence correlation and complete basis set (CBS)
limit extrapolation are used to benchmark the performance of commonly
used density functionals in computing energy barriers for Zr-mediated
reactions involving zirconocene species. These reactions include (a)
insertions of the ZrāH bond of Cp<sub>2</sub>ZrĀ(H)Cl into Cī»C,
Cī¼C, and Cī»O bonds and (b) CāH activations by
Zrī»N bond in Cp<sub>2</sub>Zrī»NH. The best performing
functionals are M06-L, M06, and M06-2X in the M06 series, all having
mean unsigned deviations (MUD) less than 2 kcal/mol. The worst performing
functional is OLYP, with a distinctly large MUD of more than 10 kcal/mol.
Considering also the trends in barrier heights and the systematic
barrier height deviation, our best recommended functional is M06-2X.
In this work, DFT empirical dispersion correction (DFT-D3) is found
to improve the performance of barrier height values for most functionals
(especially of OLYP and B3LYP). With DFT empirical dispersion correction,
we also recommend M06-2X for reaction barrier calculations of Zr-mediated
reactions
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