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981.
This longitudinal study looks at the metaphors used in a public sector information systems development project from the perspective of cognitive metaphor theory (Lakoff & Johnson, 1980 ). We examine the use of metaphors by project team members, including representatives of the users, software developers and the managers guiding the project work. The findings indicate that project team members and managers use a rich set of metaphors to make sense of the project and the records management system they are working on. Notably, distinct sets of metaphors are used in different project phases and among the project personnel and management. As the differences in the metaphors also coincide with key events in the trajectory of the project, we contend that metaphors have significant power in sensemaking, influencing action and project outcomes. In particular, we find that in highly ambiguous, knowledge‐intensive situations, metaphor use with unclear intentions and purpose hinders learning and creates more chaos than order. From a practical perspective, our study highlights the relevance of metaphor use for project management. We suggest that intentional selection of metaphors by management could be beneficial for many complex information systems projects. © 2016 John Wiley & Sons Ltd 相似文献
982.
Yamaki Yuto Sato Yuki Izui Kazuhiro Yamada Takayuki Nishiwaki Shinji Hirai Yoshikazu Tabata Osamu 《Structural and Multidisciplinary Optimization》2018,58(3):1243-1254
Structural and Multidisciplinary Optimization - Deformable mirrors are vital components in fundus imaging modality incorporating adaptive optics systems. The application of precisely controlled... 相似文献
983.
Tsuchiya T. Tabata O. Sakata J. Taga Y. 《Journal of microelectromechanical systems》1998,7(1):106-113
A new tensile tester using an electrostatic-force grip was developed to evaluate the tensile strength and the reliability of thin-film materials. The tester was constructed in a scanning electron microscope (SEM) chamber for in situ observation and was applied for tensile testing of polycrystalline silicon (poly-Si) thin films with dimensions of 30-300 μm long, 2-5 μm wide, and 2 μm thick. It was found that the mean tensile strengths of nondoped and P-doped poly-Si are 2.0-2.8 and 2.0-2.7 GPa, respectively, depending on the length of the specimens, irrespective of the specimen width. Statistical analysis of these size effects on the tensile strength predicted that the location of the fracture origin was on the edge of the specimen, which was Identified by the SEM observation of the fracture surface of the thin films 相似文献
984.
Fábio Pittoli Henrique Damasceno Vianna Jorge Luis Victória Barbosa Emerson Butzen Mari Ângela Gaedke Juvenal Soares Dias da Costa Renan Belarmino Scherer dos Santos 《Telematics and Informatics》2018,35(5):1222-1236
Noncommunicable diseases are the main reason to the rise of diseases incidence in the developed world. The management and prevention of these diseases can be done by controlling the behavioral and biological risk factors which are related to them. ChronicPrediction is an intelligent system for noncommunicable diseases care which determines in real time the impact on risk factors due to actions taken by users. Based on impact information, the system presents on users’ smartphones strategic messages to help in their treatment. ChronicPrediction applies Bayesian Networks (BNs) which use risk factors for mapping the causes of noncommunicable diseases worsening. The support to multiple chronic diseases and the integrated use of multiple BNs based on risk factors are the main contributions of this work and differentiate the proposed system from related work. We have built a functional prototype that allowed us to conduct two experiments. The first one successfully tested the main functionalities provided by ChronicPrediction to support BNs based on risk factors and the sending of messages to users’ smartphones. The evaluation involved the building of a BN for predicting coronary artery disease made with real world data obtained in a prospective cohort study. The study involved 302 patients from a hospital localized in southern Brazil. The second experiment assessed the ChronicPrediction support to multiple BNs at same time. The test involved the previous BN and another from a thirty part research work to map risk factors of diabetes. The results were encouraging and show potential for implementing ChronicPrediction in real-life situations. 相似文献
985.
Derivatives of 2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropanecarboxylic acid (chrysanthemic acid) are classic natural pyrethroids discovered in pyrethrum plants and show insecticidal activity. Chrysanthemic acid, with two asymmetric carbons, has four possible stereoisomers, and most natural pyrethroids have the (1R,3R)-trans configuration. Interestingly, chrysanthemic acid–related structures are also found in insect sex pheromones; carboxylic esters of (1R,3R)-trans-(2,2-dimethyl-3-(2-methylprop-1-enyl)cyclopropyl)methanol (chrysanthemyl alcohol) have been reported from two mealybug species. In the present study, another ester of chrysanthemyl alcohol was discovered from the striped mealybug, Ferrisia virgata (Cockerell), as its pheromone. By means of gas chromatography–mass spectrometry, nuclear magnetic resonance spectrometry, and high-performance liquid chromatography analyses using a chiral stationary phase column and authentic standards, the pheromone was identified as (1S,3R)-(?)-cis-chrysanthemyl tiglate. The (1S,3R)-enantiomer strongly attracted adult males in a greenhouse trapping bioassay, whereas the other enantiomers showed only weak activity. The cis configuration of the chrysanthemic acid–related structure appears to be relatively scarce in nature, and this is the first example reported from arthropods. 相似文献
986.
Hideki Taguchi Sayuki YamadaMahiko Nagao Yoko IchikawaKenji Tabata 《Materials Research Bulletin》2002,37(1):69-76
In preparation for synthesizing LaCoO3, gel was prepared by adding citric acid to the aqueous solution of La(NO3)3·6H2O and Co(NO3)2·6H2O. The infrared spectrum indicates that the gel prepared with 0.007 mol of citric acid is the mixture of LaCo(C6H5O7)(NO3)3, lanthanum nitrate, and cobalt nitrate, while the gel prepared with 0.011 mol of citric acid is LaCo(C6H5O7)2. Perovskite-type LaCoO3 was obtained by firing the gel above 600°C. The LaCoO3 surface was characterized by X-ray photoelectron spectroscopy and with respect to the catalytic activity of CO oxidation. 相似文献
987.
Maria Enoi Santos Miranda Catiana Marcolla Clvis Antonio Rodrígues Helena Maria Wilhelm Maria Rita Sierakowski Tania Mari Bell Bresolin Rilton Alves de Freitas 《Polymer International》2006,55(8):961-969
Chitosan (degree of deacetylation of 90.2%) and N‐carboxymethylchitosan (N‐CMCh) (degree of substitution of 18.5%) were analyzed using thermogravimetric analysis in order to determine their thermal stability. Also, their films were evaluated using scanning electron microscopy (SEM) and mechanical and dynamic mechanical analysis (DMA). Both polymers showed a thermal degradation peak at Tm ~ 250 °C, with Tonset and weight loss of 175 °C and 62% and 190 °C and 35% for chitosan and N‐CMCh, respectively. N‐CMCh showed a second thermal degradation peak at Tm = 600 °C, with an additional weight loss of 25%. Kinetic thermal analysis showed a slower process of degradation at 100 °C for N‐CMCh compared with chitosan, and an activation energy 13 times higher for the former, confirming the higher stability of N‐CMCh. Analysis of chitosan and N‐CMCh films showed that the latter support a high tension, with lower elasticity, and, as revealed by DMA, N‐CMCh has a more compact film structure, with a crossing arrangement of N‐CMCh fibers, as compared with the chitosan films which were determined from SEM analysis to have fibers in one direction only. Copyright © 2006 Society of Chemical Industry 相似文献
988.
989.
Kentaro Taki Kazuhide Tabata Shin‐ichi Kihara Masahiro Ohshima 《Polymer Engineering and Science》2006,46(5):680-690
This paper investigates the effect of rheological behavior on dynamics of bubble coalescence. In situ observations on polymers with different rheological behaviors were conducted to study coalescence dynamics. Four patterns of interface deformation were observed. Deformation during coalescence was analyzed by applying image‐processing schemes and rheological models to the in situ observations. Polymer with Newtonian behavior showed nucleation and coalescence of spherical bubbles that created a planar interface. The planar interface was deformed by a combination of biaxial and planar elongational flows. Coalescence in polymers with non‐Newtonian behavior is characterized by penetration with a parabolic shaped interface. The deformation of parabolic interface was due to biaxial elongational flow. However, the interface deformation of the polymer with cross‐linked structure was due to an integration of biaxial and elongational flow. Further, cross‐linking was also observed to have an effect on coalescence time. POLYM. ENG. SCI. 46:680–690, 2006. © 2006 Society of Plastics Engineers 相似文献
990.
Cauce Ana Mari; Domenech-Rodríguez Melanie; Paradise Matthew; Cochran Bryan N.; Shea Jennifer Munyi; Srebnik Debra; Baydar Nazli 《Canadian Metallurgical Quarterly》2002,70(1):44
In this article, a mental health help-seeking model is offered as a framework for understanding cultural and contextual factors that affect ethnic minority adolescents' pathways into mental health services. The effects of culture and context are profound across the entire help-seeking pathway, from problem identification to choice of treatment providers. The authors argue that an understanding of these help-seeking pathways provides insights into ethnic group differences in mental health care utilization and that further research in this area is needed, (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献