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991.
992.
This paper explores how countries in non-leadership positions can couple onto globally developing technological innovation systems (TISs) for renewable energy. The paper contributes to recent debates on relations between TISs and context, with a focus on how industries located in one country relate to the international TIS. Based on a survey of 102 firms in the offshore wind industry in Norway and semi-structured interviews, we find that even though Norwegian firms link up with international TISs, the lack of a domestic market represents a barrier. However, firms with activities in related industries and large firms are less exposed to this barrier. This poses a challenge as the offshore wind industry in Norway mainly consists of smaller firms. We therefore suggest that policies should aim to stimulate interaction between smaller suppliers and larger firms that potentially can act as intermediaries and provide access to international markets. 相似文献
993.
Weibull Analysis of Electrical Breakdown Strength as an Effective Means of Evaluating Elastomer Thin Film Quality
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Harald Silau Nicolai Bogø Stabell Frederik Riddersholm Petersen Martin Pham Liyun Yu Anne Ladegaard Skov 《Advanced Engineering Materials》2018,20(9)
994.
LB Johnsen P Ravn L Berglund TE Petersen LK Rasmussen CW Heegaard JT Rasmussen C Benfeldt SN Fedosov 《Canadian Metallurgical Quarterly》1998,37(36):12631-12639
Bovine tissue-type plasminogen activator (tPA) was heterologously expressed in the methylotrophic yeast Pichia pastoris and characterized structurally and kinetically. The bovine single-chain tPA-mediated activation of bovine plasminogen was studied in the presence and absence of fibrinogen fragments. We have proposed a refined new method of kinetic analysis which allows examination of both stationary and prestationary phases of this process. The investigation revealed the presence of two interconvertible forms of the recombinant bovine tPA being in equilibrium at a 1 to 50 ratio. Only the minor form was able to bind and activate plasminogen. Saturation of the whole pool of tPA required high plasminogen concentration (Km >/= 5 microM) in order to reverse the equilibrium between the two forms. Fibrinogen fragments activated the single-chain tPA due to preferential binding and stabilization of the minor "active" form of the enzyme until all the molecules of tPA were converted. The same mechanism could be applied to human tPA as well. The Km values, obtained for recombinant bovine and human tPA in the presence of fibrinogen fragments, were found to be similar (Km = 0.1 microM) while kcat of human tPA was 5-10 times higher. 相似文献
995.
R Faghih PA Lartey HN Nellans L Seif C Burnell-Curty LL Klein P Thomas A Petersen A Borre T Pagano KH Kim M Heindel YL Bennani JJ Plattner 《Canadian Metallurgical Quarterly》1998,41(18):3402-3408
In our quest toward the discovery of highly potent and acid-stable motilides, novel 4"-deoxy derivatives of 9-deoxo-6, 9-epoxyerythromycin were designed, synthesized, and evaluated for their gastrointestinal prokinetic activities. These compounds, in their 9R configuration, were more potent than their 6,9-enol ether homologues in inducing well-coordinated smooth muscle contractions in an in vitro rabbit duodenal assay: e.g., (9R), (8S)-9-deoxo-4"-deoxy-3'-N-desmethyl-3'-N-ethyl-6, 9-epoxyerythromycin A (10) and (9R), (8S)-9-deoxo-4"-deoxy-3'-N-desmethyl-3'-N-ethanol-6, 9-epoxyerythromycin A (15) had a pED50 of 8.54 and 8.11 compared to a pED50 of 7.22 for compound 2 (ABT-229). Reduction of the 6,9-enol ether, which was aimed at improving the acid stability, afforded the most stable motilides to date with t1/2 of 5.5 h for 10 and 15. Compounds 10 and 15 bind specifically to rabbit antral smooth muscle motilin receptors with pIC50 values of 8.52 and 8.70. 相似文献
996.
Jens Erik Hansen Sten Bay Jørgensen Jonathan Heath John D. Perkins 《Journal of Process Control》1998,8(3):185-195
This paper treats a case study on control structure selection for an almost binary distillation column. The column is energy integrated with a heat pump in order to transfer heat from the condenser to the reboiler. This integrated plant configuration renders the possible control structures somewhat different from what is usual for binary distillation columns. Further the heat pump enables disturbances to propagate faster through the system. The plant has six possible actuators of which three must be used to stabilize the system. Hereby three actuators are left for product purity control. An MILP screening method based on a linear state space model is used to determine economically optimal sets of controlled and manipulated variables. The generated sets of inputs and outputs are analysed with frequency dependent relative gain array (RGA), relative disturbance gain (RDG) and condition number (CN) to determine the best structure in terms disturbance rejection and setpoint tracking. The pairing and controller design are implemented and evaluated through nonlinear simulation. The suggested control structure is also qualitatively compared to a control structure applied experimentally. 相似文献
997.
Dipl.-Inf. Jens Vykoukal Dipl.-Wirtsch.-Inf. Martin Wolf Prof. Dr. Roman Beck 《WIRTSCHAFTSINFORMATIK》2009,51(2):206-214
Over the last few years Grid computing has attracted considerable attention from the industry, because it offers opportunities for new on-demand business services for enterprises. In this article, we depict the current trend of enterprises to source Grid services offered by third-party utility providers on a use-on-demand, pay-per-use basis, thus leading to faster IT response to changing business needs. We outline the emerging expansion of Grid computing in industry and discuss the significant challenges still needing to be solved to further promote the adoption of Grid technology in the business domain. 相似文献
998.
Jens Wawerla Shelley Marshall Greg Mori Kristina Rothley Payam Sabzmeydani 《Machine Vision and Applications》2009,20(5):303-317
In this paper we describe the development of the BearCam, a camera system which was deployed in Fall 2005 to monitor the behaviour
of grizzly bears at a remote location near the arctic circle. The system aided biologists in collecting the data for their
study on bears’ behavioural responses to ecotourists. We developed a camera system for operating in the challenging arctic
conditions. We describe a novel “motion shapelet” algorithm for automatically detecting bears in the video captured by this
camera system. This algorithm is an extension of the shapelet features (Sabzmeydani and Mori in CVPR 2007), which are mid-level
features capturing pieces of shape. Our extension of this technique incorporates motion information and proves effective at
automatically detecting the occurrence of bears. We present quantitative results demonstrating that our algorithm can reliably
detect bears in the vast amounts of video footage collected by our system.
相似文献
Payam SabzmeydaniEmail: |
999.
This study investigated the relationships between workers’ compliance with health and safety (H&S) routines and instructions adopted in the company (dependent variable) and psychological demands, decision authority, social support, management support, unionization and H&S management system (independent variables). A cross-sectional questionnaire study was performed among 1051 workers and the managers of 102 small- and medium-sized motor vehicle repair garages. Multilevel modeling was performed to account for the hierarchical structure of the data. At the worker level, high compliance with H&S routines correlated significantly with both social support and H&S-related management support. At the garage level, mean management support and a well-developed H&S management system correlated significantly with high workers’ compliance. Changing both the individual and contextual factors in the work environment may thus increase workers’ participation in H&S activities. 相似文献
1000.
Jens Maßberg 《Information Processing Letters》2009,109(18):1087-1083
For a set of two-element sets of non-negative real numbers we consider rooted strict binary trees with the property that the two edges leading from every non-leaf to its two children are assigned lengths l1 and l2 with {l1,l2}∈L.For choices of L for which l1+l2 is constant for every {l1,l2}∈L which models that a certain total length can be distributed with some degree of freedom specified by L to incident edges, we study the asymptotic growth of the maximum number of leaves of bounded depths in such trees and the existence of such trees with leaves at individually specified maximum depths. 相似文献