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. [32]. M.R. Gharib 1999 Vortex-induced vibration, absence of lock-in and fluid force deduction GALCIT, California Institute of Technology

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Pollack Periodica
Authors: Zoltan Vizvari, Tibor Kiss, Csaba Ver, Kalman Mathe, Bojan Kuljic, Ferenc Henezi, and Peter Odry

. , Milano L. , Russo G. High-performance modular digital lock-in amplifier , Review of Scientific Instruments , Vol. 66 , No. 6 , 1995 , pp. 3697 – 3702 . [5

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In the otherwise rich debate on the eastward expansion of the Eurozone, fragmented approaches prevail, leaving several conceptual avenues of this process underexplored. The case of Poland — initially a fervent enthusiast of the euro adoption and a somewhat assertive endorser today — offers in this context an opportunity to add to the debate and deepen our understanding of the logic behind eastward expansion of the Eurozone. In what follows, Poland's prospective Eurozone entry is examined from the broader angle of the historically determined conceptual and policy-making context of systemic transition. To this end, a conceptual nexus between Eurozone expansion and transition is established and examined through the historical institutionalist perspective. It is argued that rather than being solely a function of Poland's EU membership, both the decision to adopt the euro and the attainment of real and nominal convergence are predominantly a function of the, as yet unfinished, transition process. Interestingly, as this paper suggests, the inconsistency inherent in the execution of the Maastricht convergence criteria not only creates disincentives that effectively delay Poland's Eurozone entry but also triggers reform-drift and backsliding, thus casting a shadow on the prospect of the completion of the Polish transition and its sustainability.

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favoured regions it becomes a reason of being locked in their developmental trajectories predetermined by an irreversible past (Morgan 1997 ; Hudson 1999 ; Hong 2008 ). Amin and Cohendet ( 1999 ) suggest that codified, extra-local knowledge is an

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Abstract  

It is possible to excite by a Penning's discharge the neutral atoms sputtered during the bombardment of a target by positive ions and thus to increase the sensibility of the ionoluminescence analysis method. However, the characteristic lines of the target's elements may be masked by the discharge lines. We describe in this paper an arrangement using a lock-in amplifier which permits to reduce the discharge lines. The results obtained with a duraluminium target show that it is possible to identify the characteristic target's lines even when they are weak and near the discharge lines.

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Abstract  

The thermal behaviour of kaolinites intercalated with formamide, dimethyl sulphoxide and hydrazine has been studied by simultaneous TG-DTG-DTA-EGA and TG-MS techniques. The complexes can be decomposed completely without dehydroxylating the mineral. It was found that the amount of intercalated guest molecules per inner surface OH-group is close to unity for the formamide and dimethyl sulphoxide intercalates. For the intercalation of hydrazine it was found that hydrazine is locked in the expanded mineral as hydrazine hydrate and its amount is somewhat higher than that obtained for the other two reagents. The thermal evolution patterns of the guest molecules revealed that all the three reagents are bonded at least in two different ways in the interlayer space.

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Abstract  

We have designed, built and calibrated a microcomputer-controller automated a.c. calorimeter for liquid crystals and solid samples, in the temperature range from 30 to 250°C, in which we enhance several features of previous ones reported in the literature. We have incorporate the lock-in amplifier model 5302 from EG&G in our set-up, which permits to extend the frequency range to 1 mHz. This allows the performance of suitable frequency sweeps in order to choose the optimum operating frequency for low thermal conductivity materials. The calorimeter has been calibrated with the 8OCB liquid crystal compound. The resolution obtained forC p values was better than 0.1% and the absolute erroer around 5%. As applications, we show the ferroelectric transition of the triglicerine sulphate (TGS), the Nematic-Smetic A transition of the 8OCB and a study in a binary system of ferroelectric liquid crystals, SCE9-SCE10.

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The construction, the isothermal operation (26.2±0.06) and the calibration of a differential calorimeter of high performance are described. Its construction is based on the conduction principle by using copper resistors noninductively coiled on thin aluminium cylinders used as temperature sensors with very low inertia. Thermal flows are measured by using an ac bridge with a lock-in amplifier. The calibration, both of the height (h) and of the area (A) of the recorded peaks, is performed by using calibrated heat pulsesw p with errors under 0.5%. A reproducible value of ratioh/A is obtained on a large number ofw p values, which represents a figure of merit of the high-performance calorimeter. This value is an immediate index of the nature of the general transformation process. For a clear-cut definition of the process, the universal procedure recently established on the topoenergetic principles is applied.

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Abstract

This study examines the impact of collaborating patterns on the R&D performance of public research institutions (PRIs) in Korea's science and engineering fields. For the construction of R&D collaborating networks based on the co-authorship data of 127 institutions in Scopus, this paper proposes four types of collaborations by categorizing network analyses into two dimensions: structural positions (density, efficiency, and betweeness centrality) and the relational characteristics of individual nodes (eigenvector and closeness centralities). To explore the research performance by collaboration type, we employ a data envelopment analysis window analysis of a panel of 23 PRIs over a 10-year period. Comparing the R&D productivities of each group, we find that the PRIs of higher productivity adhere to a cohesive networking strategy, retaining intensive relations with their existing partners. The empirical results suggest that excessively cohesive alliances might end up in ‘lock-in’ relations, hindering the exploitation of new opportunities for innovation. These findings are implicit in relation to the Korean Government's R&D policies on collaborating strategies to produce sustained research results with the advent of the convergence research era.

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Summary The curing behaviour of commercial UF and MUF resins, stored at room temperature nearly up to gelation, is studied by simultaneous TG-DTA technique and structural changes of resins are also followed during aging. On the basis of 13C NMR spectra, the main chemical reaction during UF resin storage is the formation of methylenes and dimethylene ethers linked to secondary amino groups. Aging of resins results in a decrease of cure rate which is related to lower concentration of active functional groups and decrease in molecular mobility. On DTA curve, the resin with higher content of methylol groups reveals the curing exotherm earlier. With decreasing methylol content during storage, the peak maximum of exotherm is shifted to higher temperature value. Advanced polycondensation and sedimentation processes during storage produce partly locked in macromolecule structure water, and the water evaporation endotherm on DTA curve shifts to considerably higher temperature. The aged MUF resins are chemically less changed than UF resins and the aging process mainly involves noncovalent network formation due to complex molecular structure.

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