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61.
Assurance has different meanings, depending on the source, audience, and interpretation. We applied institutional theory and the Capability Maturity Model to conceptualize assurance: its symbolic aspects to gain social acceptance, and its substantive aspects to improve organizational capability and effectiveness in performing IS security risk management (SRM). An empirical study examined assurance-seeking behavior and outcomes for regulatory compliance. Some degree of process maturity in SRM was found necessary for producing convincing verbal accounts and compliance evidence. Findings suggest that unless an organization's assurance claims are based on achieving Level 4 maturity, assurance will be based more on symbolism than effectiveness. 相似文献
62.
The self-vibratory drilling (SVD) is an innovative technology that allows increasing the productivity, without coolant. The aim of this paper is to prove that the environmental impacts of SVD are significantly less than those of traditional drilling (TD) and to quantify them. The study is based on a life cycle analysis of both processes. The major contributor to the environmental impacts in TD is the coolant. The new major contributors in SVD are the twist drills. A model that links the lifespan of the twist drills and the environmental impacts of SVD has been developed to support decisions for R&D. 相似文献
63.
Lessons learned from an empirical study of the early design phases of an unfulfilled innovation 总被引:1,自引:1,他引:0
Jérémy Legardeur Jean François Boujut Henri Tiger 《Research in Engineering Design》2010,21(4):249-262
This paper presents the results of an empirical study focused on the observation and analysis of an innovative design process.
We have had the opportunity to observe and participate in the early phase of a new innovative project within a design office
of a truck manufacturer. Our observations based on the actor-network theory highlight the importance of the various design
rationales carried by the actors involved. The results of this study show the weakness and complexity of an innovative process
within a highly constrained environment. We particularly show that carrying out innovation requires different viewpoints with
regard to the object of the design to evolve along with the network of actors and the organisation involved. The issue of
product and process integration involving knowledge transfer between actors throughout the design process is also discussed
here. As a result, we highlight the importance of rethinking the interface role played by the material expert (in our case)
and, in line with other works, we put forward the “interface actor” as the key network actor involved during the early development
phases. To provide the network and the interface actor with a means to share information and co-operate during these informal
early design phases we propose some features of a new web-based information system and the basis for a debate on the idea
lifecycle management concept as a solution to the issue of innovative idea information structuring. 相似文献
64.
65.
Critères généraux de conception des réseaux de diodes lasers à rubans couplés par champs évanescents
Françoise Lozes-Dupuy Sophie Bonnefont Alain Bensoussan Michèle Delort Georges Vassilieff Henri Martinot 《电信纪事》1989,44(3-4):135-141
The aim of this article is to define the general criteria for design of phase-locked diode laser arrays. A general method for designing these devices is presented using the effective index method and the coupled mode theory. The confinement required for the individual diodes is defined, and the allowed structure geometries are determined. 相似文献
66.
Ricardo K. Donato Moisés A. Benvegnú Luciano G. Furlan Raquel S. Mauler Henri S. Schrekker 《应用聚合物科学杂志》2010,116(1):304-307
This article describes the application of ionic liquid 1‐decyl‐3‐methylimidazolium tetrafluoroborate in the preparation of polypropylene‐silica composites. The sol‐gel technology was used to prepare xerogel silica‐ionic liquid hybrid S1 , which was obtained as a free flowing powder of aggregated spherical particles. Ionic liquid free silica S2 was obtained by extraction and calcination of S1 . Melt blending of isotactic polypropylene with S1 and S2 afforded the composites C1 (with ionic liquid) and C2 (without ionic liquid), respectively. The presence of ionic liquid on the S1 silica surface promoted significantly improved silica dispersion in the polymer matrix and prevented compression of the silica particles. Furthermore, the crystallization temperature of composite C1 was significantly higher, which indicated that silica‐ionic liquid filler S1 acted as nucleating agent. The resistance to thermal decomposition of both composites was increased, but this was higher in the presence of ionic liquid. These results show that liquid salts can function as coupling agents and compatibalizers for the preparation of polymeric composites with differentiated properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
67.
68.
Hammurabi is a software application designed to help the UNIX system administrator to evaluate better the consequences of the actions he/she carries out, in order to maintain the system and to make it change. In this paper, we describe the implementation of Hammurabi's inference engine. This engine is a multiactor Prolog-like engine. The actors have, on the one hand, the ability to spy the events occurring inside the whole machine (inside the engine, and inside the UNIX OS), and on the other hand, the ability to forbid or to freeze some events. This ability is used as a synchronization mechanism. In the first part of this paper, we describe the data representation. In its second part, we describe the implementation of the spying mechanism. 相似文献
69.
Eddy Collin Laure Filleau Thierry Fournier Yuriy M. Bunkov Henri Godfrin 《Journal of Low Temperature Physics》2008,150(5-6):739-790
Nowadays microfabrication techniques originating from micro-electro nics enable to create mechanical objects of micron-size.
The field of Micro-Electro-Mechanical devices (MEMs) is continuously expanding, with an amazingly broad range of applications
at room temperature.
Vibrating objects (torsional oscillators, vibrating wires) widely used at low temperatures to study quantum fluids, can be
replaced advantageously by Silicon MEMs. In this letter we report on the study of Silicon vibrating wire devices. A goal-post
structure covered with a metal layer is driven at resonance by the Laplace force acting on a current in a magnetic field,
while the induced voltage arising from the cut magnetic flux allows to detect the motion. The characteristics of the resonance
have been studied from 10 mK to 30 K, in vacuum and in 4He gas. In this article, we focus on the results obtained above 1.5 K, in vacuum and gas, and introduce some features observed
at lower temperatures.
The resonant properties can be quantitatively understood by means of simple models, from the linear regime to a highly non-linear
response at strong drives. We demonstrate that the non-linearity is mostly due to the geometry of the vibrators. We also show
that in our device the friction mechanisms originate in the metallic layers, and can be fully characterized. The interaction
with 4He gas is fit to theory without adjustable parameters.
相似文献
70.
Ali Sarhadi Jesper Henri Hattel Hans Nørgaard Hansen Cem Celal Tutum Lasse Lorenzen Peter M.W. Skovgaard 《Journal of Materials Processing Technology》2012,212(8):1771-1779
In the precision glass moulding process, the heat transfer and the resulting transient temperature distributions of the molten glass are of great importance because they significantly affect the productivity as well as the thermally induced residual stresses in the final product. Thermal modelling of the heating system in the glass moulding process considering detailed heating mechanisms therefore plays an important part in optimizing the heating system and the subsequent pressing stage in the lens manufacturing process.The current paper deals with three-dimensional transient thermal modelling of the multi-stage heating system in a wafer based glass moulding process. In order to investigate the importance of the radiation from the interior and surface of the glass, a simple finite volume code is developed to model one dimensional radiation–conduction heat transfer in the glass wafer for an extreme case with very high temperature difference considering temperature dependant thermal conductivity and heat capacity. Afterwards, by using three-dimensional FEM modelling along with a predefined experimental test, the equivalent glass–mould interface contact resistance is determined for two different pressures. Finally, the three-dimensional modelling of the multi-stage heating system in the wafer based glass moulding process is simulated with the FEM software ABAQUS for a particular industrial application for mobile phone camera lenses to obtain the temperature distribution in the glass wafer. In the numerical modelling, the interface boundary conditions for each heating stage are changed according to the determining heat transfer mechanism(s). Numerical results are compared with experimental data to show the validity of the numerical modelling. The obtained results show that the right thermal modelling is highly dependent on the proper choice of thermal boundary conditions in different stages according to the real physical phenomena behind the process. 相似文献