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Abstract

In this paper a sample rate conversion algorithm which allows for continuously changing resampling ratio has been presented. The proposed implementation is based on a variable fractional delay filter which is implemented by means of a Farrow structure. Coefficients of this structure are computed on the basis of fractional delay filters which are designed using the offset window method. The proposed approach allows us to freely change the instantaneous resampling ratio during processing. Using such an algorithm we can simulate recording of audio on magnetic tape with nonuniform velocity as well as remove such distortions. We have demonstrated capabilities of the proposed approach based on the example of speech signal processing with a resampling ratio which was computed on the basis of estimated fundamental frequency of voiced speech segments.

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Authors and Affiliations

Marek Blok
Piotr Drózda
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Abstract

Tests for combustion of hay and sunflower husk pellets mixed with wood pellets were performed in a horizontal-feed as well as under-feed (retort) wood pellet furnace installed in boilers with a nominal heat output of 15 and 20 kW, located in a heat station. During the combustion a slagging phenomenon was observed in the furnaces. In order to lower the temperature in the furnace, fuel feeding rate was reduced with unaltered air stream rate. The higher the proportion of wood pellets in the mixture the lower carbon monoxide concentration. The following results of carbon monoxide concentration (in mg/m3 presented for 10% O2 content in flue gas) for different furnaces and fuel mixtures (proportion in wt%) were obtained: horizontal-feed furnace supplied with hay/wood: 0/100 - 326; 30/70 - 157; 50/50 - 301; 100/0 - 3300; horizontal-feed furnace supplied with sunflower husk/wood: 50/50 - 1062; 67/33 - 1721; 100/0 - 3775; under-feed (retort) furnace supplied with hay/wood: 0/100 - 90; 15/85 - 157; 30/70 - 135; 50/50 - 5179; under-feed furnace supplied with sunflower husk/wood: 67/33 - 2498; 100/0 - 3128. Boiler heat output and heat efficiency was low: 7 to 13 kW and about 55%, respectively, for the boiler with horizontal-feed furnace and 9 to 14 kW and 64%, respectively, for the boiler with under-feed furnace.

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Authors and Affiliations

Marek Juszczak
Katarzyna Lossy
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Abstract

Recent empirical research has provided compelling evidence that the proliferation of intellectual property rights (IP) and the fragmentation of patent rights among different patent holders have created barriers to innovation and impediments to the commercialization of scientific discoveries. Legal and economic scholars have suggested that due to the rising number of patent applications, the limited resources in patent offices around the world and the lack of sufficient time to prior art search, examiners have failed to conduct thorough patent examination processes. Moreover, researchers have linked the growing number of overlapping intellectual property rights to the tragedy of the anticommons and to the concept of patent thickets. Multiple studies have been performed in order to develop measures that could verify the existence of patent thickets and to better understand the social and economic impact of fragmentary patent owners. When it comes to the energy sector, the problem of patent thickets is now even more important. As the technological innovation in this sector increases and the energy-related patenting continues to grow, it has been argued that the issue of patent thickets may have a direct impact on investment decisions and the long-run development of this sector. This paper presents an overview of literature on the definition of a patent thicket and summarizes some of the possible factors causing thickets to arise. Additionally, it discusses the recent developments in patent thicket measures and patent thicket identification methods.

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Authors and Affiliations

Pablo Benalcazar
Jacek Kamiński
Przemysław Kaszyński
ORCID: ORCID
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Abstract

Helicopters of the Medical Air Rescue (LPR) help transport the patients to large hospitals quickly. The requirements for the space around the helipad and flight safety mean that more elevated helipads than ground helipads are built at hospitals located in proximity to the city centres. Elevated helipads can vary in design and location depending on the opportunities offered by the hospital buildings and their surroundings. The Vibroacoustic Laboratory of the Warsaw Institute of Aviation took measurements to determine the impact of a helicopter on a hospital elevated helipad during landing or taking off. Helicopter landings are neither frequent nor long, however, they can have a significant impact on a helipad structure, the hospital building itself and its patients, staff or equipment. The impact of the helicopter includes both the noise, vibrations transmitted by the helicopter chassis and air pulsations under the rotor (low-frequency ones). This paper discusses some methods used for measuring vibration properties of several elevated helipads and building recorded during the landing and take-off of the EC135 helicopter. The sample results of such tests are also presented. The tests discussed can be used to verify both the assumptions and calculations referring to helipads and to meet the requirements of the standards in the field of noise and vibrations.
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Bibliography

[1] Act dated 8 September 2006 r. on National Medical Rescue (J. of L. 191 No. 1410).
[2] Regulation of the Min. of Health, 27 June 2019 on the hospital emergency department (J. of L. 2019 No. 1213)
[3] Federal Aviation Administration, US Department of Transportation, 2012, Heliport Design -AC 150/5390-2c, Chapter 4 - Hospital Heliports.
[4] K. Wąchalski, „Wyniesione lądowiska dla helikopterów na budynkach szpitalnych” (Elevated helipads on hospital buildings), „Inżynier Budownictwa”, Warsaw, 2018.
[5] K. Wąchalski, “Assessment of the current construction conditions for elevated helipad on hospital buildings in Poland”, Warsaw, Prace Instytutu Lotnictwa No. 3 (244), pp 189–201, 2016, http://dx.doi.org/10.5604/05096669.1226158
[6] Polish Standard PN-B-02171_2017 “Ocena wpływu drgań na ludzi w budynkach” (Assessment of the effects of vibration on people in buildings).
[7] S. Cieślak, W. Krzymień, “Initial analysis of helicopter impact on hospital helipads”, Transactions of the Institute of Aviation (256), Warsaw, pp 14 –23, 2019, https://doi.org/10.2478/tar-2019-0014
[8] W. Krzymień, S. Cieślak, “Investigation of the vibration properties of concrete elevated hospital helipads”, Vibrations in Physical Systems No. 31, Poznan, 2020.
[9] M. Szmidt, W. Krzymień, S. Cieślak, “Vibration properties of steel constructed hospital elevated helipads”, Transactions on Aerospace Research (260), Warsaw, pp 11–20 , 2020. https://doi.org/10.2478/tar-2020-0013
[10] Eric E. Ungar, “Vibration criteria for healthcare facility floors”, Sound & Vibration, 41(9) pp. 26–27, 2007.
[11] P. Ruchała, K. Grabowska “Problems of an aerodynamic interference between helicopter rotor slipstream and an elevated heliport”, Journal of KONES Powertrain and Transport, Vol. 26, No. 3, 2019, http://dx.doi.org/10.2478/kones-2019-0072
[12] A. Dziubiński, A. Sieradzki, R. Żurawski, “The elevated helipads – study of wind and rotor wash influence for most common configuration types”, 44th European Rotorcraft Forum, Netherlands, 2018.
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Authors and Affiliations

Wiesław Krzymień
1
ORCID: ORCID

  1. Łukasiewicz Research Network – Institute of Aviation, Al. Krakowska 110/114, 02-256 Warsaw
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Abstract

Low concentrations of phytoplankton (average 2.5 x 104 to б.0 х 105 cells l-1) were found at ten stations surveyed in the region of the Weddell-Scotia Confluence. Phytoflagellates represented mainly by 1—3 μm picoplankton were prevalent among the algae, contributing 65—100% to the total numbers: this group is observed to dominate over diatoms in areas of intensive water mixing. Maximum concentrations of phytoplankton at one station, reaching down to 200 m, were due to a physical aggregation of cells by confluencing and downwelling waters. The average for the water column quantities of the same algal groups were nearly identical at most stations, but peak numbers occurred in the 0—75 m surface layer. Differences in diatom assemblages were associated with the complex hydrography of the WSC region.

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Authors and Affiliations

Elżbieta E. Kopczyńska

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