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Number of results: 11
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Abstract

The paper deals with recent developments in the fields of applied mathematics and operational research triggered by the needs of effective support of environmental policy-making processes that require interdisciplinary science-based advice. Mathematical models developed for this purpose demand new modeling paradigms for an adequate integration of pertinent knowledge. and creation of knowledge needed for rational decision-making. The article first summarizes the model-based support for problem solving from the point of view of actual decision-makers. Next, il discusses the model representation of the knowledge pertinent lo a given decision-making problem, and the recently developed modeling technology supporting the whole process of modeling complex problems. The last parł deals with novel methods and tools for integrated management of risks related to natural catastrophes. The presented methodology is illustrated by its application lo actual environmental policy-making support.
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Authors and Affiliations

Marek Makowski
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Abstract

With the development of wireless power transfer technology, more and more attention has been paid to its electromagnetic safety. In this paper, a novel hybrid shielding structure composed of the innermost fan-shaped ferrite, the interlayer nanocrystalline strip and the outermost aluminum foil is proposed to shield the electromagnetic field of the inductive power transfer system. Eight structure parameters of the proposed shielding are optimized by finite element simulation, in order to reduce the magnetic leakage of the system and improve the utilization rate of shielding materials. In addition, the proposed structure is compared with two types of typical double-layer hybrid shielding from the perspectives of the weight, the coupling coefficient and the magnetic flux leakage. Both simulation and experiment results show that the cost and weight of the proposed shield are about 60% lower than the traditional disk shield. Moreover, the shielding layer proposed in this paper can not only effectively reduce the magnetic flux leakage of the system, but also maintain a high coupling coefficient.
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Bibliography

[1] Zhang Z., Pang H., Georgiadis A., Cecati C., Wireless Power Transfer—An Overview, IEEE Transactions on Industrial Electronics, vol. 66, no. 2, pp. 1044–1058 (2019).
[2] Kalwar K.A., Aamir M., Mekhilef S., Inductively coupled power transfer (ICPT) for electric vehicle charging – A review, Renewable and Sustainable Energy Reviews, vol. 47, pp. 462–475 (2015).
[3] Machura P., Li Q., A critical review on wireless charging for electric vehicles, Renewable and Sustainable Energy Reviews, vol. 104, pp. 209–234 (2019).
[4] Li H., Wang C., Liu Y., Yue R., Research on Single-Switch Wireless Power Transfer System Based on SiC MOSFET, IEEE Access, vol. 7, pp. 163796–163805 (2019).
[5] Zheng J., Wang C., Xia D., Design and analysis of the ferrite air-gapped cores for a resonant inductor[ J], Archives of Electrical Engineering, vol. 67, pp. 579–589 (2018).
[6] Xu H., Wang C., Xia D., Liu Y., Design of Magnetic Coupler for Wireless Power Transfer, Energies, vol. 12, no. 15 (2019).
[7] Christ A., Douglas M.,Nadakuduti J.,Kuster N., Assessing Human Exposure to Electromagnetic Fields from Wireless Power Transmission Systems, Proceedings of the IEEE, vol. 101, no. 6, pp. 1482–1493 (2013).
[8] Ding P., Bernard L., Pichon L., Razek A., Evaluation of Electromagnetic Fields in Human Body Exposed to Wireless Inductive Charging System, IEEE Transactions on Magnetics, vol. 50, no. 2, pp. 1037–1040 (2014).
[9] International Commission on Non-Ionizing Radiation Protection Guidelines for limiting exposure to time-varying electric and magnetic fields (1 Hz to 100 kHz), Health Phys., vol. 99, pp. 818–836 (2010).
[10] Tan L., Elnail K.E.I., Ju M., Huang X., Comparative Analysis and Design of the Shielding Techniques in WPT Systems for Charging EVs, Energies, vol. 12, no. 11 (2019).
[11] Choi S.Y., Gu B.W., Lee S.W., Lee W.Y., Huh J., Rim C.T., Generalized Active EMF Cancel Methods forWireless Electric Vehicles, IEEE Transactions on Power Electronics, vol. 29, no. 11, pp. 5770–5783 (2014).
[12] Zhu Q., Zhang Y., Guo Y., Liao C.,Wang L.,Wang L., Null-Coupled Electromagnetic Field Canceling Coil for Wireless Power Transfer System, IEEE Transactions on Transportation Electrification, vol. 3, no. 2, pp. 464–473 (2017).
[13] Zeng H., Liu Z., Hou Y., Hei T., Zhou B., Optimization of Magnetic Core Structure for Wireless Charging Coupler, IEEE Transactions on Magnetics, vol. 53, no. 6, pp. 1–4 (2017).
[14] Houji L., Chunfang W., Zhihao W., Dan L., Research of shield structure for wireless power transfer system, Advanced Technology of Electrical Engineering and Energy, vol. 38, no. 5, pp. 74–83 (2019).
[15] Stergiou C.A., Zaspalis V., Impact of Ferrite Shield Properties on the Low-Power Inductive Power Transfer, IEEE Transactions on Magnetics, vol. 52, no. 8, pp. 1–9 (2016).
[16] Wen F., Huang X., Optimal Magnetic Field Shielding Method by Metallic Sheets in Wireless Power Transfer System, Energies, vol. 9, no. 9 (2016).
[17] Li J., Huang X., Chen C., Tan L., Wang W., Guo J., Effect of metal shielding on a wireless power transfer system, AIP Advances, vol. 7, no. 5 (2017).
[18] Park H.H.,Kwon J.H.,Kwak S.I., Ahn S., Magnetic Shielding Analysis of a Ferrite Plate with a Periodic Metal Strip, IEEE Transactions on Magnetics, vol. 51, no. 8, pp. 18 (2015).
[19] Park H.H., Kwon J.H., Kwak S.I., Ahn S., Effect of Air-Gap Between a Ferrite Plate and Metal Strips on Magnetic Shielding, IEEE Transactions on Magnetics, vol. 51, no. 11, pp. 1–4 (2015).
[20] Kim H., Song C., Kim D., Jung D.H., Kim I., Kim Y., Kim J., Ahn S., Kim J., Coil Design and Measurements of Automotive Magnetic Resonant Wireless Charging System for High-Efficiency and Low Magnetic Field Leakage, IEEE Transactions on Microwave Theory and Techniques, vol. 64, no. 2, pp. 1–18 (2016).
[21] Kim S., Covic G.A., Boys J.T., Tripolar Pad for Inductive Power Transfer Systems for EV Charging, Transactions on Power Electronics, vol. 32, no. 7, pp. 5045–5057 (2017).
[22] Kim M., Byun J., Lee B.K., Performance Analysis of Magnetic Power Pads for Inductive Power Transfer Systems with Ferrite Structure Variation, Journal of Electrical Engineering and Technology, vol. 12, pp. 1211–1218 (2017).
[23] Budhia M., Boys J.T., Covic G.A., Huang C., Development of a Single-Sided Flux Magnetic Coupler for Electric Vehicle IPT Charging Systems, IEEE Transactions on Industrial Electronics, vol. 60, no. 1, pp. 318–328 (2013).
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Authors and Affiliations

Yun Rui Liu
1
Chunfang Wang
1
Dongwei Xia
1
Rui Yue
1

  1. Qingdao University, China
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Abstract

The 2150 km2 transboundary Gurara Reservoir Catchment in Nigeria was modelled using the Water Evaluation and Planning tool to assess the hydro-climatic variability resulting from climate change and human-induced activities from 1989 to 2019 and projected to the future till 2050. Specifically, the model simulated the historic dataset and predicted the future runoff. The initial results revealed that monthly calibration/validation of the model yielded acceptable results with Nash–Sutcliff efficiency ( NSE), percent bias ( PBIAS), and coefficient of determination (R2) values of 0.72/0.69, 0.72/0.67 and 4.0%/1.0% respectively. Uncertainty was moderately adequate as the model enveloped about 70% of the observed runoff. Future predicted runoffs were modelled for climate ensembles under three different representative concentration pathways (RCP4.5, RCP6.5 and RCP8.5). The RCP projections for all the climate change scenarios showed increasing runoff trends. The model proved efficient in determining the hydrological response of the catchment to potential impacts from climate change and human-induced activities. The model has the potential to be used for further analysis to aid effective water resources planning and management at catchment scale.
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Authors and Affiliations

Francis Ifie-emi Oseke
1
ORCID: ORCID
Geophery Kwame Anornu
1
Kwaku Amaning Adjei
1
ORCID: ORCID
Martin Obada Eduvie
1

  1. National Water Resources Institute, Mando, P.MB 2309, Kaduna, Nigeria
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Abstract

The article presents the algorithm that enables adaptive determination of the amplification coefficient in the filter equation provided by Kalman. The method makes use of an estimation error, which was defined for this purpose, and its derivative to determine the direction of correction changes of the gain vector. This eliminates the necessity to solve Riccati equation, which causes reduction of the method computational complexity. The experimental studies carried out using the proposed approach relate to the estimation of state coordinates describing river pollution using the BOD (biochemical oxygen demand) and DO (dissolved oxygen) indicators).The acquired results indicate that the suggested method does better estimations than the Kalman filter. Two indicators were used to measure the quality of estimates: the Root Mean Squared Error (RMSE) and the Mean Percentage Error (MPE).
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Authors and Affiliations

Tadeusz Kwater
1
ORCID: ORCID
Przemysław Hawro
1
ORCID: ORCID
Jacek Bartman
2
ORCID: ORCID
Damian Mazur
3
ORCID: ORCID

  1. Institute of Technical Engineering, The State University of Technology and Economics in Jaroslaw, Czarnieckiego 16, 37-500 Jaroslaw, Poland
  2. Faculty of Natural Sciences, University of Rzeszow, Pigonia 1, 35-959 Rzeszów, Poland
  3. Faculty of Electrical and Computer Engineering, Rzeszow University of Technology, 35-959 Rzeszów, Pola 2, Poland
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Abstract

This article engages in detailed discussion of the material properties of water pipes made of polyethylene (PE). It describes the influence of properties of the material (including its geometric dimensions) on the level of reliability of pipelines made from PE 100. Values for the index of reliability obtained from analyses carried out using probabilistic methodswere compared with those recommended for the index in regard to a reference period of 50 years and different Reliability Classes (RCs). The fully probabilistic (3rd level) method – Monte Carlo simulation method was used to analyze the reliability. The probabilistic calculations were carried out with account taken of different values for the coefficient of variation describing material parameters, adopted as random variables; as well as the correlations between them. The work detailed here reports an influence of material geometry on the reliability index reported for the analysed pipeline made from PE. Where the analysed PE pipe was associated with a coefficient of variation for wall thickness at or over 0.07, this denoted non-compliance with standard PN-EN 1990:2002 as regards the minimum level of reliability recommended for a reference period of 50 years and Reliability Class RC2.
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Bibliography

[1] European Standard. EN 1990: Eurocode – Basis of structural design. 2004.
[2] International Standard. ISO 2394: General principles on reliability for structures. 2015.
[3] ASTM International Standard. D 3350: Standard Specification for Polyethylene Plastics Pipe and Fittings Materials. 2014.
[4] K. Bortel, “Wpływ wybranych czynników na trwałosc rur z tworzyw termoplastycznych”, Przetwórstwo Tworzyw, 2011, vol. 17, no. 6, pp. 559–566.
[5] Y.G. Hsuan, R.M. Koerner, “Antioxidant Depletion Lifetime in High Density Polyethylene Geomembranes”, Journal of Geotechnical and Geoenvironmental Engineering, 1999, vol. 124, pp. 532–541.
[6] E. Kuliczkowska, A. Kuliczkowski, B. Tchórzewska-Cieslak, “The structural integrity of water pipelines by considering the different loads”, Engineering Failure Analysis, 2020, vol. 118, pp. 1–11, DOI: 10.1016/j.engfailanal.2020.104932.
[7] A.H. Awad, A.A. Abd El-Wahab, R. El-Gamsy, M.H. Abdel-Latif, “A study of some thermal and mechanical properties of HDPE blend with marble and granite dust”, Ain Shams Engineering Journal, 2019, vol. 10, pp. 353–358, DOI: 10.1016/j.asej.2020.02.001.
[8] X.T. Zheng, X.H. Zhang, L.W. Ma, W. Wang, J.Y. Yu, “Mechanical characterization notched high density polyethylene (HDPE) pipe: Testing and prediction”, International Journal of Pressure Vessels and Piping, 2019, vol. 173, pp. 11–19, DOI: 10.1016/j.ijpvp.2019.04.016.
[9] L-E. Janson, Plastics Pipes for Water Supply and Sewage Disposal, 4th ed. Stockholm: Borealis, 2003.
[10] International Standard. ISO 13477: Thermoplastics pipes for the conveyance of fluids – Determination of resistance to rapid crack propagation (RCP) – Small-scale steady-state test (S4 test). 2008.
[11] D. Castagnetti, E. Dragoni, G. ScireMammano, N. Fontani, I. Nuccini, V. Sartori, “Effect of sodium hypochlorite on the structural integrity of polyethylene pipes for potable water conveyance”, Proceedings of Plastic Pipes XIV, Budapest, 2008.
[12] F. Majid, F.M. Elghorba, “Critical lifetime of HDPE pipes through damage and reliability models”, Journal of Mechanical Engineering and Sciences, 2019, vol. 13, pp. 5228–5241.
[13] S. Vlase, D.D. Scarlatescu, M.L. Scutaru, “Stress Field in Tubes Made of High Density Polyethylene Used in Water Supply Systems”, Acta Technica Napocensis, 2019, vol. 62, pp. 273–280.
[14] The Design Of Buried Thermoplastics Pipes. [Online]. Available: https://www.prik.pl/images/pdf/ bibliografia/DesignOfBuriedPipesArecentUpdate-PDF.pdf. [Accessed: 24.11.2020].
[15] S. MacKellar, “UKWIR National Mains Failure Database”, in Proceedings of the Plastic Pipes XIII. Washington, 2006.
[16] S. Burn, P. Davis, T. Schiller, “Long-Term Performance Prediction for PVC Pipes”, AWWA Report 91092F, 2006.
[17] M. Kwietniewski, J. Rak, Niezawodnosc infrastruktury wodociagowej i kanalizacyjnej w Polsce.Warszawa: Polska AkademiaNauk.Komitet Inzynierii Ladowej i Wodnej. Instytut Podstawowych Problemów Techniki, 2010.
[18] “Flexible and rigid sewer pipes in Europe: Comparing performance and environmental impact”, Report on the TEPPFA-PLASTICS EUROPE. Sustainable Municipal Pipes Project, 2005.
[19] European Standard. EN 12201: Polyethylene (PE) pipes for water supply, and for drainage and sewerage under pressure – dimensions. 2011.
[20] International Standard. ISO 13761: Plastics pipes and fittings – Pressure reduction factors for polyethylene pipeline systems for use at temperatures above 20 degrees C. 2017.
[21] S. Wolinski, Podstawy Projektowania Konstrukcji”, in Budownictwo ogólne, Warszawa PWN, 2011.
[22] M. Słowik, I. Skrzypczak, R. Kotynia, M. Kaszubska, “The Application of a Probabilistic Method to the Reliability Analysis of Longitudinally Reinforced Concrete Beams”, Procedia Engineering, 2017, vol. 193, pp. 273–280, DOI: 10.1016/j.proeng.2017.06.214.
[23] J. Szyszka, J. Kogut, I. Skrzypczak,W. Kokoszka, “Selective Internal Heat Distribution in Modified Trombe Wall”, IOP Conference Series: Earth and Environmental Science, 2017, vol. 95, no. 4, DOI: 10.1088/1755-1315/95/4/042018.
[24] International Standard ISO 12162: Thermoplastics materials for pipes and fittings for pressure applications – Classification, designation and design coefficient. 2009.
[25] M. Bournonville, J. Dahnke, D. Darwin, “Statistical Analysis of the Mechanical Properties and Weight of Reinforcing Bars”, Structural Engineering and Engineering Materials, SL 04–1, 2004.
[26] M. Kwietniewski, K. Miszta-Kruk, ”Unreliability of Water Supply Networks in the Polish Towns Based on the Field Reliability Tests”, in Proceedings of The European Safety And Reliability Conference, Esrel, Troyes France, 2011.
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Authors and Affiliations

Andrzej Studzinski
1
ORCID: ORCID
Vlasta Ondrejka Harbulakova
2
ORCID: ORCID
Izabela Skrzypczak
1
ORCID: ORCID

  1. Rzeszow University of Technology, Faculty of Civil and Environmental Engineering and Architecture, ul. Poznanska 2, 35-084 Rzeszów, Poland
  2. Technical University of Kosice, Faculty of Civil Engineering, Vysokoskolská 4, 042 00 Košice, Slovak Republic
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Abstract

In the heterogeneous economic space, big cities are development poles that are usually characterized by the best conditions for running a business and the highest level and living conditions. Their role in development processes is the subject of many discussions. On 23 October 2017, at the invitation of the Mayor of Cracow, J. Majchrowski, an external Plenary meeting of the Committee for Spatial Development of the Polish National Academy of Sciences was held in Cracow, the aim of which was to discuss the role of big cities in Poland›s socio-economic development. This article presents the author›s opinions in a synthetic way, presenting the most important issues raised by him during the panel on the importance of Polish metropolises in shaping the development potential of the country and the region. In addition to the fundamental terminological and problematic discussion, the article describes the experience of Poznań as an agglomeration signifi cantly aff ecting the development of the region, formulating in the summary recommendations referring to the practice of regional policy.

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Authors and Affiliations

Paweł Churski
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Abstract

Geological carbon dioxide storing should be carried out with the assumption that there are no leakages from the storage sites. However, regardless of whether the gas which is injected in leaks from the storage site or not, the carbon dioxide stored will influence the environment. In a tight storage site the carbon dioxide injected in will dissolve in the reservoir liquids (groundwater and oil) and react with the rocks of the storage formation. Dissolving CO2 in underground water will result in the change of its pH and chemism. The reactions with the rock matrix of the storage site will not only trigger changes in its mineralogical composition, but also in the petrophysical parameters, because of the precipitation and dissolution of minerals. A leakage of CO2 from its storage site can trigger off changes in the composition of soil air and groundwater, influence the development of plants, and in case of sudden and large leaks it will pose a threat for people and animals. Carbon dioxide can cause deterioration of the quality of drinking waters related to the rise in their mineralization (hardness) and the mobilization of heavymetals' cations. A higher content of this gas in soil leads to a greater acidity and negatively affects plants. A carbon dioxide concentration of ca. 20-30% is a critical value for plants above which they start to die. The influence of high concentrations of carbon dioxide on the human organism depends on the concentration of gas, exposure time and physiological factors. CO2 content in the air of up to 1.5% does not provoke any side effects in people. A concentration of over 3% has a number of negative effects, such as: higher respiratory rate, breathing difficulties, headaches, loss of consciousness. Concentrations higher than 30% lead to death after a few minutes. Underground microorganisms and fungi have a good tolerance to elevated and high concentrations of carbon dioxide. Among animals the best resistance is found in invertebrates, some rodents and birds.

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Authors and Affiliations

Barbara Uliasz-Misiak
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Abstract

This paper discusses the transient characteristics of the planar type SOFC cell stack, of which the standard output is 300 W. The transient response of the voltage to the manipulation of an electric current was investigated. The effects of the response and of the operating condition determined by the operating temperature of the stack were studied by mapping a current-voltage (I-V) correlation. The current-based fuel control (CBFC) was adopted for keeping the fuel utilization factor at constant while the value of the electric current was ramped at the constant rate. The present experimental study shows that the transient characteristics of the cell voltage are determined by primarily the operating temperature caused by the manipulation of the current. Particularly, the slope of the I-V curve and the overshoot found on the voltage was remarkably influenced by the operating temperature. The different values of the fuel utilization factor influence the height of the settled voltages. The CBFC has significance in determining the slope of the I-V characteristic, but the different values of the fuel utilization factor does not affect the slope as the operating temperature does. The CBFC essentially does not alter the amplitude of the overshoot on the voltage response, since this is dominated by the operating temperature and its change is caused by manipulating the current.
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Authors and Affiliations

Janusz S. Szmyd
Yosuke Komatsu
Grzegorz Brus
Francesco Ghigliazza
Shinji Kimijima
Anna Ściążko
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Abstract

In 2016 near Bornity (Braniewo district) a so far unknown stronghold was discovered. Within a small area the researchers unearthed a quarter of an early ̔Abbāsid dirham, a bronze spur with bent-in hooked extremities and a fragment of a ring of the Perm-Glazow-Duesminde type. In 2017 a preliminary small test excavation was carried out at the site. The discovered items and radiocarbon analysis of the charcoals from the rampart structure indicate that the site was in use in the last decades of the 9th century and the first quarter of the 10th century. Among the discovered artefacts the Arabic dirhams (two Hārūn ar-Rašīd’s dirhams and one al-Mahdī’s coin) deserve special attention and are discussed in detail in the article.

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Authors and Affiliations

Sławomir Wadyl
Kacper Martyka
Dorota Malarczyk
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Abstract

Galicia’s autonomous status was in fact a doubletrack affair. On the one hand Galicia became a shining example of freedom and autonomy, embedded in the new constitutional order of the Austro-Hungarian Empire, while on the other hand it was tied down to a monarchical absolutism which offered only limited protection of individual rights. The press in particular was caught in the dilemmas produced by this situation, especially in the sensitive areas of political loyalty and religion.

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Authors and Affiliations

Elżbieta A. Maj
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Abstract

The paper outlines the Catholic and the Evangelical standpoint on the primate’s function served by the Bishop of Rome and its origin. The controversy revolves around the key phrase, iure divino and iure humano, which points to the divine or human origin of the primacy. In the Catholic perspective, Jesus Christ brought the Church into existence and provided this institution with permanent structural elements: primacy and apostolate. This thesis, considered an imperative of faith, is based on the texts of the Gospel which underscore the primacy of Saint Peter the Apostle among the Twelve and in the early Church. According to the Catholic ecclesiology, it was not only a private privilege enjoyed by Peter but a permanent element of the structure of the Church, which received the formal status of a dogma at the First Vatican Council. From the outset, the Reformation has assumed that primacy is an element shaped in the course of the historical development of the Church. The ecumenical dialogue between Catholicism and Lutheranism led to the establishment of a standpoint veering towards the consideration of the origin of primacy as a matter of lesser consequence. This step was taken in order to underscore the communal dimension of the Church, with its important function in unifying Christianity and presenting it to the world. The basic premise giving credence to this function is its foundation in the Gospel.

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Authors and Affiliations

Marek Żmudziński

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