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1.
AI & SOCIETY - This paper is addressed to recent theoretical discussions of the Anthropocene, in particular Bernard Stiegler’s Neganthropocene (Open Universities Press, 2018), which... 相似文献
2.
We propose a general modeling framework to evaluate the performance of cache consistency algorithms. In addition to the usual hit rate, we introduce the hit* rate as a consistency measure, which captures the fraction of non-stale downloads from the cache. We apply these ideas to the analysis of the fixed TTL consistency algorithm in the presence of network delays. The hit and hit* rates are evaluated when requests and updates are modeled by renewal processes. Classical results on the renewal function lead to various bounds. 相似文献
3.
T.S. Nguyen A.P.S. Selvadurai G. Armand 《International Journal of Rock Mechanics and Mining Sciences》2005,42(5-6):639
Buffer materials being considered as engineered barriers in nuclear fuel waste (NFW) disposal systems possess a pronounced nonlinear behaviour in the unsaturated state. In order to simulate such non-linear responses,the authors adopted an incrementally nonlinear poro-elastic approach where the coefficients of the governing equations are assumed to be functions of suction and the void ratio. These functions are in turn developed from a state-surface equation obtained from suction-controlled oedometric tests. In this paper we show the derivation of the governing equations of the poro-elastic model. A finite element computer code, FRACON, was developed by the authors to numerically solve the above equations. We first use the code to simulate laboratory tests to characterize the swelling properties of a typical bentonite. That same bentonite was used in the FEBEX in-situ heater experiment, conducted at the Grimsel site, Switzerland. The FRACON code was also used to perform blind predictions of the FEBEX heater experiment. It is shown that the model correctly predicts drying of the bentonite near the heaters and re-saturation near the rock interface. The evolution of temperature and the heater thermal output were also reasonably well predicted by the model. The trends in the total stresses developed in the bentonite were correctly predicted; the absolute values however were underestimated probably due to the omission of pore pressure build-up in the rock mass. 相似文献
4.
The effects, during formation, of current density, charge capacity, and concentration and temperature of H2SO4 electrolyte on the capacity of tubular electrodes in lead/acid batteries have been studied. Electrode capacity was found to be maximum at a H2SO4 concentration of 1.05 sp. gr., a charge amount of 250% theoretical capacity, a current density of 0.44 A dm?2, and an electrolyte temperature of 40 °C. A study of the soaking process for tubular electrodes showed the electrode capacity to be maximum when the acid absorption was about 170 mg of H2SO4 per g of oxide. Finally, the discharge overpotential of tubular electrodes was analyzed by a galvanostatic transient method. 相似文献
5.
The reactivity of hexamethylphosphorus triamide, (P[N? (CH3)2]3) (HPT), with cotton cellulose was examined under various conditions. HPT was found to react readily with the cellulose to produce a cellulose phosphite and/or phosphate ester having approximately one acidic hydrogen atom per phosphorus atom. The reaction of HPT with cotton cellulose was efficiently catalyzed by dimethylamine hydrochloride (1%). The phosphorus content imparted by the catalyzed reaction on cotton fabrics was approximately twice that imparted by the uncatalyzed reaction. Flame resistance of the treated fabrics ranged from fair to excellent. The treated fabrics also exhibited ion exchange properties and some crosslinking. 相似文献
6.
Marketing Activities to Support ‘Moderately Novel’ Product Innovation: Insights from the Chemical Industry 下载免费PDF全文
Scholars often follow a contingency approach to study which marketing activities are suitable for a particular type of product innovation project, thereby making a distinction between incremental and radical innovation only. ‘Moderately novel’ projects, which have intermediate levels of newness, have therefore not been given due attention. This paper focuses on market intelligence generation and the creation of cross‐functional linkages as marketing activities that are important in the context of moderately novel product innovation. In addition, the organizational position of the marketers involved in these activities is dealt with. Based on the analysis of four successful projects in the chemical industry, we argue, firstly, that moderately novel innovation projects have their own particular sets of marketing practices and, secondly, that differences exist between projects aiming at a new market segment and projects in which novelty is not related to market segment but to other market dimensions. These differences are especially salient in early project phases. These findings are pertinent to research on the role of marketers in product innovation, and to the study of organizational ambidexterity. 相似文献
7.
Recent advances in design theory help clarify the logic, forms and conditions of generativity. In particular, the formal model of forcing predicts that high-level generativity (so-called generic generativity) can only be reached if the knowledge structure meets the ‘splitting condition’. We test this hypothesis for the case of Bauhaus (1919–1933), where we can expect strong generativity and where we have access to the structures of knowledge provided by teaching. We analyse teaching at Bauhaus by focusing on the courses of Itten and Klee. We show that these courses aimed to increase students’ creative design capabilities by providing the students with methods of building a knowledge base with two critical features: (1) a knowledge structure that is characterized by non-determinism and non-modularity and (2) a design process that helps students progressively ‘superimpose’ languages on the object. From the results of the study, we confirm the hypothesis deduced from design theory; we reveal unexpected conditions on the knowledge structure required for generativity and show that the structure is different from the knowledge structure and design process of engineering systematic design and show that the conditions required for generativity, which can appear as a limit on generativity, can also be positively interpreted. The example of Bauhaus shows that enabling a splitting condition is a powerful way to increase designers’ generativity. 相似文献
8.
We present a primal–dual augmented Lagrangian method to solve an equality constrained minimization problem. This is a Newton-like method applied to a perturbation of the optimality system that follows from a reformulation of the initial problem by introducing an augmented Lagrangian function. An important aspect of this approach is that, by a choice of suitable updating rules of parameters, the algorithm reduces to a regularized Newton method applied to a sequence of optimality systems. The global convergence is proved under mild assumptions. An asymptotic analysis is also presented and quadratic convergence is proved under standard regularity assumptions. Some numerical results show that the method is very efficient and robust. 相似文献
9.
10.
N. A. Armand A. I. Zakharov 《Journal of Communications Technology and Electronics》2006,51(10):1141-1147
The influence of the ionosphere on polarization characteristics of the electromagnetic radiation of a spacebome synthetic-aperture radar is analyzed. The value of the Faraday rotation angle of a linearly polarized wave radiated by this radar into the ionosphere is estimated for a comparatively long-wave band. A technique is proposed for determining the Faraday rotation angle by measuring the reflectivity of the Earth’s surface with a polarimetric radar. This technique is independent of the mapped geometry and orientation of reflected elements of the Earth’s surface. 相似文献