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Number of results: 14
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Abstract

The paper discusses the mode of land acquisition for public road development resulting from the process of land severance performed at the request of the owner in terms of: the legitimacy of land acquisition by the State Treasury or local government units, by virtue of law, upon the land severance approval, the compensation for taking over the land severed for roads, the possibility of restitution of partially acquired plots of land in case a road has not been constructed, and therefore the redundancy of land earmarked for public purposes. The author compares land acquisition procedures set out in historical and currently applicable regulations as well as obligation to pay compensation. The aim of the research is to answer the question of whether the regulations according to which the land allocated for roads is acquired by operation of law by public entities should be modified, and if so, to what extent. On the example of a selected city, research was carried out to determine whether the acquired land is used at a later stage for road construction and what is the scale of compensation claims paid by the municipality. The conducted research made it possible to propose solutions to modify the mode of land severance resulting in land being severed for road development, considering both rational property management and the rights of former owners for restitution in the event public entities failed to use this real property for public purposes.
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Authors and Affiliations

Anna Trembecka
1
ORCID: ORCID

  1. AGH University of Science and Technology, Krakow, Poland
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Abstract

I n t r o d u c t i o n: Fecal calprotectin (FC) rises significantly in intestinal inflammation accompanied by neutrophil activation — such as Clostridium diffi cile infection (CDI). The aim of the study was to evaluate the benefi t of FC testing in assessing the severity of CDI.

Ma t e r i a l s a n d M e t h o d s: The study group included 76 patients with CDI hospitalized in the Jagiellonian University Hospital in Krakow from July 2017 till January 2018. FC levels were measured using an EIA (Enzyme Immunoassay). Demographic, clinical information and blood tests were recorded using standardized data collection forms. The selection of patients into non-severe and severe groups was carried out in accordance with the ESCMID criteria (European Society of Clinical Microbiology and Infectious Diseases) and some modifications to those criteria were proposed.

R e s u l t s: The studied population included 76 patients (39 men and 37 women) with CDI aged from 24 to 98 years (mean: 72). Median calprotectin level was 739 (Q25–Q75: 612–799 μg/g), characteristic of patients with colitis. A statistically signifi cant diff erence in FC concentration in patients with severe vs non-severe CDI was observed (severe — 770 vs non-severe — 659 μg/g, p = 0.009). FC directly correlated with platelets level; however, no correlation between FC level and the blood parameters prognostic for CDI (leukocyte, neutrophil count, albumin, creatinine levels) was found.

C o n c l u s i o n: FC level is an indication of ongoing intestinal inflammation in CDI patients. FC level significantly correlated with CDI severity, which demonstrates that FC could serve as a predictive marker for assessing CDI severity.

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Authors and Affiliations

Mirosław Dróżdż
Grażyna Biesiada
Hanna Pituch
Dorota Wultańska
Piotr Obuch-Woszczatyński
Michał Piotrowski
Jolanta Kędzierska
Mateusz Michalak
Aleksander Garlicki
Jacek Czepiel
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Abstract

In a deregulated electricity market, it is important to dispatch the generation in an economical manner and to ensure security under different operating conditions. In this study evolutionary computation based solution for optimal power flow is attempted. Social welfare optimization is taken as the objective function, which includes generation cost, transmission cost and consumer benefit function. Transmission cost is calculated using Bialek’s power flow tracing method. Severity index is applied as a constraint to measure the security. The objective function is calculated for pre and post contingency periods. Real power generations, real power loads and transformer tap settings are selected as control variables. Different bilateral and multilateral conditions are considered for analysis. A Human Group Optimization algorithm is used to find the solution of the problem. The IEEE 30 bus system is taken as a test system.

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Authors and Affiliations

Bastin Solai Nazaran J.
K. Selvi
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Abstract

In this paper voltage stability is analysed based not only on the voltage deviations from the nominal values but also on the number of limit violating buses and severity of voltage limit violations. The expression of the actual state of the system as a numerical index like severity, aids the system operator in taking better security related decisions at control centres both during a period of contingency and also at a highly stressed operating condition. In contrary to conventional N – 1 contingency analysis, Northern Electric Reliability Council (NERC) recommends N – 2 line contingency analysis. The decision of the system operator to overcome the present contingency state of the system must blend harmoniously with the stability of the system. Hence the work presents a novel N – 2 contingency analysis based on the continuous severity function of the system. The study is performed on 4005 possible combinations of N – 2 contingency states for the practical Indian Utility 62 bus system. Static VAr Compensator is used to improve voltage profile during line contingencies. A multi- objective optimization with the objective of minimizing the voltage deviation and also the number of limit violating bus with optimal location and optimal sizing of SVC is achieved by Particle Swarm Optimization algorithm.
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Authors and Affiliations

S.P. Mangaiyarkarasi
T. Sree Renga Raja
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Abstract

The forming limit of AZ31 alloy, a representative Mg-Al-Zn-based wrought alloy, and the effect of severe plastic deformation (SPD) by examining the microstructure change caused by dynamic recrystallization led by high temperature and high dislocation density at 300℃ using a biaxial alternate forging (BAF) were investigated in this study. As a result of BAF test for AZ31 Mg alloy, significant cracks on the ends of workpieces occurred after 7 passes. The microstructure of as-extruded specimen showed the non-uniform distribution of the relatively coarse grains and the fine grains considered to be sub-grains. However, as the number of passes increases, the area of coarse grains gradually disappeared and the fine grains became more dominant in the microstructures. The result of tensile test for workpieces with each forging pass showed an increase in strength depending on pass number was shown with a slight increase of elongation. The Electron Backscatter Diffraction (EBSD) results exhibited that, the microstructure showed the presence of coarse grains and twins after only 1 pass, while the grains appeared to be significantly refined and uniformly distributed after 3 pass, at which the strength and elongation began to increase, simultaneously.
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Authors and Affiliations

Young-Chul Shin
1
ORCID: ORCID
Seong-Ho Ha
1
ORCID: ORCID
Abdul Wahid Shah
1
ORCID: ORCID

  1. Korea Institute of Industrial Technology (KITECH), Molding & Metal Forming R&D Department, 156 Gaetbeol-ro, Yeonsu-gu, Incheon 21999, Republic of Korea
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Abstract

This study was undertaken to investigate the effect of severe plastic deformation (SPD) by extrusion combined with reversible torsion (KoBo) method on microstructure and mechanical properties of Al-5Cu and Al-25Cu alloys. The extrusion combined with reversible torsion was carried out using reduction coefficient of λ = 30 and λ = 98. In this work, the microstructure was characterized by light microscopy (LM), scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM). Compression test and tensile test were performed for deformed alloys. The binary Al-5Cu and Al-25Cu alloys consist of the face cantered cubic (FCC) α phase in the form of dendrites and tetragonal (C16) θ-Al2Cu intermetallic phase observed in interdentritic regions. The increase of Cu content leads to increase of interdentritic regions. The microstructure of the alloys is refined after applying KoB deformation with λ = 30 and λ = 98. Ultimate Tensile Strength (UTS) of Al-5Cu alloy after KoBo deformation with λ = 30 and λ = 98 reached about 200 MPa. UTS for samples of Al-25Cu with λ = 30 and λ = 98 increased compared to Al-5Cu alloy and exceed 320 MPa and 270 MPa respectively. All samples showed increase of plasticity with increase of reduction coefficient. Independently of reduction coefficient, the compressive strain of Al-5Cu alloys is about 60%. The Al-25Cu alloy with λ = 98 showed the value of compressive strain exceed 60%, although for this same alloy but with λ = 30, the compressive strain is only 35%.

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Authors and Affiliations

K. Rodak
A. Brzezińska
J. Sobota
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Abstract

The present paper focuses on the analysis of resistance of several prototypical under sleeper pads (USP) to severe environmental conditions. Taking into account the climate in Poland, evaluation of USP in regard to water and frost resistance should be performed and the influence of high temperatures should be analyzed. In the present paper results of several tests carried out on the selected USP are presented. The tests were performed in accordance with the rules given in PN-EN 16730. Concrete blocks with USP were immersed in water at room temperature for 24 h and then placed in a climatic chamber for resistance testing. The results show that the severe environmental conditions influence the damping-related parameters of USP, which affects the effectiveness of the vibration isolation. The performed analyses allowed the authors to indicate the most resistant pads that will undergo further testing. Additionally, requirements of several railway infrastructure managers as well as authors' recommendations concerning the properties of USP were given.
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Bibliography


[1] C. Jayasuriya, B. Indraratna, T. Ngoc Ngo, “Experimental study to examine the role of under sleeper pads for improved performance of ballast under cyclic loading”, Transportation Geotechnics 19: pp. 61–73, 2019. https://doi.org/10.1016/j.trgeo.2019.01.005
[2] C. Kraśkiewicz, A. Zbiciak, W. Oleksiewicz, W. Karwowski, “Static and Dynamic Parameters of Railway Tracks Retrofitted With Under Sleeper Pads”, Archives of Civil Engineering 64(4): pp. 187–201, 2018. https://doi.org/10.2478/ace-2018-0070
[3] M. Sol-Sánchez, F. Moreno-Navarro, C. Rubio-Gámez, “The use of elastic elements in railway tracks: A state of the art review”, Construction and Building Materials 75: pp. 293–305, 2015. https://doi.org/10.1016/j.conbuildmat.2014.11.027
[4] M. Sol-Sánchez, L. Pirozzolo, F. Moreno-Navarro, C. Rubio-Gámez, “A study into the mechanical performance of different configurations for the railway track section: A laboratory approach”, Engineering Structures 119: pp. 13–23, 2016. https://doi.org/10.1016/j.engstruct.2016.04.008
[5] M. Sol-Sánchez, F. Moreno-Navarro, C. Rubio-Gámez, “The Use of Deconstructed Tires as Elastic Elements in Railway Tracks”, Materials 7: 5903–5919, 2014. https://doi.org/10.3390/ma7085903
[6] M. Sol-Sánchez, N.H. Thom, F. Moreno-Navarro, C. Rubio-Gámez, G.D. Airey, “A study into the use of crumb rubber in railway ballast” Construction and Building Materials 75: pp. 19–24, 2015. https://doi.org/10.1016/j.conbuildmat.2014.10.045
[7] J. Kennedy, P.K. Woodward, G. Medero, M. Banimahd, “Reducing railway track settlement using three-dimensional polyurethane polymer reinforcement of the ballast” Construction and Building Materials 44: pp. 615–625, 2013. https://doi.org/10.1016/j.conbuildmat.2013.03.002
[8] S. Kaewunruen, A. Aikawa, A.M. Remennikov, “Vibration attenuation at rail joints through under sleeper pads”. Procedia Engineering 189: pp. 193-198, 2017. https://doi.org/10.1016/j.proeng.2017.05.031
[9] A. Omodaka, T. Kumakura, T. Konishi, “Maintenance reduction by the development of resilient sleepers for ballasted track with optimal under-sleeper pads”, Procedia CIRP 59: pp. 53–56, 2017. https://doi.org/10.1016/j.procir.2016.09.039
[10] T. Abadi, L. Le Pen, A. Zervos, W. Powrie, “Effect of Sleeper Interventions on Railway Track Performance”, Journal of Geotechnical and Geoenvironmental Engineering 145(4): 04019009, 2019. https://doi.org/10.1061/(ASCE)GT.1943-5606.0002022
[11] C. Jayasuriya, B. Indraratna, T.N. Ngo, “Experimental study to examine the role of under sleeper pads for improved performance of ballast under cyclic loading”, Transportation Geotechnics 19: pp. 61–73, 2019. https://doi.org/10.1016/j.trgeo.2019.01.005
[12] C. Kraśkiewicz, A. Zbiciak, A. Al Sabouni-Zawadzka, A. Piotrowski, “Experimental Research on Fatigue Strength of Prototype under Sleeper Pads Used in the Ballasted Rail Track Systems”, Archives of Civil Engineering 66(1): pp. 241–255, 2020. https://doi.org/10.24425/ace.2020.131786
[13] Zbiciak, C. Kraśkiewicz, Al Sabouni-Zawadzka, J. Pełczyński, S. Dudziak, “A Novel Approach to the Analysis of Under Sleeper Pads (USP) Applied in the Ballasted Track Structures”, Materials 13(11): p. 2438, 2020. https://doi.org/10.3390/ma13112438
[14] IRS 70713-1: Railway Application – Track & Structure “Under Sleeper Pads (USP) - Recommendations for Use”, 1st edition 01.04.2018.
[15] PN-EN 16730:2016-08 Railway applications – track – concrete sleepers and bearers with under sleeper pads.
[16] RFI TCAR SF AR 03 007 C, Specifica tecnica di fornitura: Tappetini sotto traversa (USP), 2017.
[17] SNCF IG04013 Traverses et supports béton pour pose ballastée équipées de semelles résilientes en sous faces (ex CT IGEV 016) 14.08.2018.
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Authors and Affiliations

Cezary Kraśkiewicz
1
ORCID: ORCID
Artur Zbiciak
1
ORCID: ORCID
Anna Al Sabouni-Zawadzka
1
ORCID: ORCID

  1. Warsaw University of Technology, Faculty of Civil Engineering, Al. Armii Ludowej 16, 00-637 Warsaw, Poland
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Abstract

In response to stresses, plants are capable of communicating their physiological status to other individuals in the community using several chemical cues. Nearby receivers then adjust their own homeostasis to increase resilience. The majority of studies to date have concentrated on the communication of abiotic stressors (e.g., salinity or drought) or herbivory. Less attention has been paid to the role of communication during microbial infections and almost nothing has focused on viruses. Here we investigated the effect that the prevalence of a turnip mosaic virus in a community of Arabidopsis thaliana has on the severity of symptoms developed in a group of receivers. First, we looked at the influence of two factors on the kinetics of symptom progression in the receivers, namely the prevalence of infection among emitters and the growth stage of the receiver plants at inoculation. We found that young receiver plants developed milder symptoms than older ones, and that high infection prevalence resulted in slower disease progression in receivers. Second, we tested the possibility that jasmonates could act as chemical signaling cues. To do this, we examined the kinetics of symptom progression in jasmonate-insensitive and wild-type plants. The results showed that the protective effect vanished in the mutant plants. Third, we investigated the possibility that root communication could also be relevant. We found that the kinetics of symptom progression across receivers was further slowed down in an age-dependent manner when plants were planted in the same pot. Together, these preliminary findings point to a potential function for disease prevalence in plant communities in regulating the severity of symptoms, this effect being mediated by some volatile organic compounds.
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Authors and Affiliations

Francisca de la Iglesia
1
Santiago F. Elena
1 2

  1. Instituto de Biología Integrativa de Sistemas (I2SysBio), CSIC-Universitat de València, CL.Catedrático Agustín Escardino Belloch 9, Paterna, 46980 València, Spain
  2. Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA
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Abstract

Microstructure and texture of the CuCr0.6 alloy processed by rolling with cyclic movement of rolls (RCMR) at room temperature were investigated. The RCMR processing was applied for the samples in different initial conditions in the solid solution followed by quenching into iced water at 1000oC for 3 h and in aging treatment conditions performed at 500oC for 2 h and at 700oC for 24 h. Application of the solution and aging processes prior to RCMR deformation results in the partial dissolution of Cr particles into the Cu matrix and precipitation of the second phase particles. RCMR processing with value of the total effective strain (εft) of 5 was introduced to the material. It was found that the RCMR method is effective in texture weakening. The obtained results revealed that there is a large similarity in texture orientations after RCMR processing independently of heat treatment conditions. Cyclic character of deformation leads to an incomplete transition of LAB to HAB.

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Authors and Affiliations

A. Urbańczyk-Gucwa
A. Brzezińska
B. Adamczyk-Cieślak
ORCID: ORCID
K. Rodak
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Abstract

Two strength-age hardening aluminum-lithium alloys: Al-2.3wt%Li and Al-2.2wt%Li-0.1wt%Zr in two different heat treatment conditions: solution state (S) and additionally in aging state (A) were severely plastically deformed by rolling with cyclic movement of rolls (RCMR) method to produce ultrafine – grained structure. Two thermo-mechanical treatments were used: (S+A+RCMR) and (S+RCMR+A+RCMR). To investigate the combined effect of plastic deformation and heat treatment, tensile tests were performed. Microstructural observations were undertaken using scanning transmission electron microscopy (STEM), and scanning transmission electron microscopy (SEM) equipped with electron backscattering diffraction detector (EBSD). Based on the obtained results, it can be deduced that maximum mechanical properties as: yield strength (YS) and ultimate tensile strength (UTS) could be achieved when the microstructure of alloys is in (S+A+RCMR) state. For samples in (S+RCMR+A+RCMR) state, ductility is higher than for (S+A+RCMR) state. The microstructural results shows that the favourable conditions for decreasing grain size of alloys is (S+A+RCMR) state. Additionally, in this state is much greater dislocation density than for (S+RCMR+A+RCMR) state. The microstructure of alloys in (S+RCMR+A+RCMR) state is characterized by grains/subgrains with higher average diameter and with higher misorientation angles compared with (S+A+RCMR) state.

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Authors and Affiliations

A. Brzezińska
A. Urbańczyk-Gucwa
R. Molak
K. Rodak
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Abstract

To understand the contributory factors to rear-end accident severity on mountainous expressways, a total of 1039 rear-end accidents, occurring on G5 Jingkun Expressway from Hechizhai to Qipanguan in Shaanxi, China over the period of 2012 to 2017, were collected, and a non-parametric Classification and Regression Tree (CART) model was used to explore the relationship between severity outcomes and driver factors, vehicle characteristics, roadway geometry and environmental conditions. Then the random forest model was introduced to examine the accuracy of variable selection and rank their importance. The results show that driver’s risky driving behaviours, vehicle type, radius of curve, angle of deflection, type of vertical curve, time, season, and weather are significantly associated with rear-end accident severity. Speeding and driving while drunk and fatigued are more prone to result in severe consequences for such accidents and driving while fatigued is found to have the highest fatality probability, especially during the night period (18:00–24:00). The involvement of heavy trucks increases the injury probability significantly, but decreases the fatality probability. In addition, adverse weather and sharp curve with radius less than 1000mare the most risk combination of factors. These findings can help agencies more effectively establish stricter regulations, adopt technical measures and strengthen safety education to ensure driver’s driving safety on mountainous expressways for today and tomorrow.
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Authors and Affiliations

Yonggang Wang
1
ORCID: ORCID
Xianyu Luo
1
ORCID: ORCID

  1. Chang’an University, College of Transportation Engineering, Middle Section of South 2 Ring Rd., Xi’an 710064, Shaanxi, China
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Abstract

Oxide-dispersion-strengthened high-entropy alloys were produced by hot-pressing a ball-milled mixture of Y2O3 and atomized CoCrFeMnNi powder. The effect of milling duration on grain size reduction, oxide formation behavior, and the resulting mechanical properties of the alloys was studied. Both the alloy powder size and Y2O3 particle size decreased with milling time. Moreover, the alloy powder experienced severe plastic deformation, dramatically generating crystalline defects. As a result, the grain size was reduced to ~16.746 nm and in-situ second phases (e.g., MnO2 and σ phase) were formed at the defects. This increased the hardness of the alloys up to a certain level, although excessive amounts of in-situ second phases had the reverse effect.
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Bibliography

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Authors and Affiliations

Yongwook Song
1
ORCID: ORCID
Daeyoung Kim
1
ORCID: ORCID
Seungjin Nam
1
ORCID: ORCID
Kee-Ahn Lee
2
ORCID: ORCID
Hyunjoo Choi
1
ORCID: ORCID

  1. Kookmin University, School of Materials Science and Engineering, Seoul, Republic of Korea
  2. Inha University, Department of Materials Science and Engineering, Incheon 22212, Republic of Korea
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Abstract

The objective of the present study was to identify the dynamics of Alternaria blight spread on spring oilseed rape lower, middle and upper leaves and siliques, to determine the disease incidence (DI) and severity (DS) on leaves, stems, siliques and seeds under the effect of prochloraz and tebuconazole. Efficiency of the fungicides was compared in relation to their application time. Field experiments with the spring oilseed rape cv. 'Star' were conducted at the Lithuanian Institute of Agriculture during 1997-1999.
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Authors and Affiliations

Irena Brazauskiene
Egle Petraitiene
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Abstract

Range-gated-imaging system, which can be used to eliminate backscatter in strong scattering environments, is based on two high speed technologies. It uses high power, ultra-short pulse laser as the light source. And it opens the optical gate of an ICCD camera with a micro-channel-plate image intensifier in a very short time while the laser pulses reflected by the object is coming back to the ICCD camera. Using this range-gated-imaging technology, the effect of scattered light can be reduced and a clear image is obtained.

In this paper, the test results of the range-gated-imaging system under dense aerosol environments, which simulates environments in the reactor containment building when the severe accident of the nuclear power plant occurred, are described. To evaluate the observation performance of the range-gated-imaging system under such dense fog environment, we made a test facility. Fog particles are sprayed into the test facility until fog concentration is reached to the postulated concentration level of the severe accident of the nuclear power plant. At such dense fog concentration conditions, we compared and evaluated the observation performances of the range-gated-imaging system and the CCD camera.

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Authors and Affiliations

J.W. Cho
Y.S. Choi
K.M. Jeong

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