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Abstract

This paper describes the arithmetic blocks based on Montgomery Multiplier (MM), which reduces complexity, gives lower power dissipation and higher operating frequency. The main objective in designing these arithmetic blocks is to use modified full adder structure and carry save adder structure that can be implemented in algorithm based MM circuit. The conventional full adder design acts as a benchmark for comparison, the second is the modified Boolean equation for full adder and third design is the design of full adder consisting of two XOR gate and a 2-to-1 Multiplexer. Besides Universal gates such as NOR gate and NAND gate, full adder circuits are used to further improve the speed of the circuit. The MM circuit is evaluated based on different parameters such as operating frequency, power dissipation and area of occupancy in FPGA board. The schematic designs of the arithmetic components along with the MM architecture are constructed using Quartus II tool, while the simulation is done using Model sim for verification of circuit functionality which has shown improvement on the full adder design with two XOR gate and one 2-to-1 Multiplexer implementation in terms of power dissipation, operating frequency and area.

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Authors and Affiliations

P. Velrajkumar
C. Senthilpari
J. Sheela Francisca
T. Nirmal Raj
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Abstract

Reinforced concrete composite slab consists of a thin prefabricated slab in which span reinforcement is located and of concrete joined with the slab, with such concrete being laid on site.

The existence of a joint of two concretes in such floors is interpreted as introducing a contact layer into a monolithic slab. In the paper parameters of two models are estimated. The first is a model of a contact layer and the second is a model of a composite slab with a single degree of freedom. The models consider that the contact has elastic properties and inelastic properties causing energy dissipation. Experimental investigations are discussed further based on which the parameters values of the contact layer model were determined.

Delamination was experienced for the slabs characterised by low contact layer stiffness after applying a maximum load. In addition, the strains of a contact layer having low stiffness are accompanied by lower energy dissipation than of a layer with high stiffness.

The smaller stiffness of composite floors, as compared to monolithic floors, occurs as a consequence of the existence of a joint. Such decrease for a composite slab is interpreted in the model with a single degree of freedom as the serial connection of stiffness of a monolithic slab and an element considering the existence of a contact layer.

The stiffness of an element considering the existence of a contact layer decreases along with a load, and the elements corresponding to the higher stiffness of the contact layer are characterised by higher energy dissipation.

The aforementioned results of the investigations confirm the assumptions of the contact layer model and a composite slab model with a single degree of freedom. The findings made represent a basis for establishing a method of evaluating the condition of a joint in composite slabs according to statistical investigations.

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Authors and Affiliations

K. Gromysz
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Abstract

In this work, steady flow-field and heat transfer through a copper-water nanofluid around a rotating circular cylinder, dissipating uniform heat flux, with a constant non-dimensional rotation rate varying from 0 to 5 was investigated numerically using a finite-volume method for Reynolds numbers from the range 10–40. Furthermore, the range of nanoparticle volume fractions considered is 0–5%. The variation of the local and the average Nusselt numbers with Reynolds number, volume fractions, and rotation rate are presented for the range of conditions. The average Nusselt number is found to increase with increasing the nanoparticle volume fractions and decrease with increasing value of the rotation rate.

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Authors and Affiliations

Rafik Bouakkaz
Abded El Ouahed Ouali
Yacine Khelili
Salhi Faouzi
Ilyes Tiauiria
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Abstract

Tomato is an economically important vegetable crop which is attacked heavily by insect pests leading to reduction of yield and quality of the fruits. Field experiments were carried out to investigate the dissipation of methomyl (a common insecticide) used mainly on tomato fruits. LC-MS/MS coupled with the QuEChERS method were used for the determination of methomyl. The results showed that the recovery using matrix-matched standards ranged from 87.8 to 101.3%, with relative standard deviation of 2.5 to 7.5%. Kinetics equation, Log R = log R0 – 0.434 Kt, was used to calculate the rate of degradation in tomato, soil and water. Residue half-life calculated using kinetic rate ranged from 1.95 to 1.63 days in tomato and soil, respectively. From the results it was concluded that tomato fruits can be safely harvested for consumption after 15 days of application based on estimated preharvest interval (PHI). It is advisable to re-estimate the PHI regularly owing to data from the EU and Codex.

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Authors and Affiliations

Dalia El-Hefny
Ibrahim Abdallah
Rania Helmy
Hend Mahmoud
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Abstract

Previous researchers have been widely studied the equation for calculating the energy dissipation in USBR Type IV, applied in the stilling basin structure as an energy dissipator. However, inefficient energy dissipating basins are commonly found in the field due to the large discharge and high water head, potentially damaging the bottom of the energy dissipating basin and its downstream river. Therefore, an energy dissipator plan fulfilling the safe specifications for the flow behaviour that occurred is required. This study aimed to determine the variation of the energy dissipators and evaluate their effect on the hydraulic jump and energy dissipation. For this purpose, a physical model was undertaken on the USBR Type IV spillway system. The novelty of this experiment showed that combination and modification dissipation features, such as floor elevation, end threshold and riprap lengthening, could effectively dissipate the impact of energy downstream. The final series exhibited a significantly higher Lj/y1 ratio, a favourable condition due to the compaction of the hydraulic jump. There was also a significant increase in the downstream tailwater depth (y2) during the jump formation. Therefore, the final series energy dissipator was better in the stilling basin design for hydraulic jump stability and compaction. The increase in energy dissipation for the final series type was the highest (98.4%) in Q2 and the lowest (84.8%) in Q10 compared to the original series. Therefore, this type can better reduce the cavitation risk damaging to the structure and downstream of the river.
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Authors and Affiliations

Alfiansyah Yulianur Bantacut
1
ORCID: ORCID
Azmeri Azmeri
1
ORCID: ORCID
Faris Zahran Jemi
2
ORCID: ORCID
Ziana Ziana
1
ORCID: ORCID
Muslem Muslem
1

  1. Universitas Syiah Kuala, Faculty of Engineering, Civil Engineering Department, Syech Abdur-Rauf No 7, Darussalam, 23111, Banda Aceh, Indonesia
  2. Universitas Syiah Kuala, Faculty of Engineering, Electrical Engineering Department, Banda Aceh, Indonesia
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Abstract

Energy dissipator functions to dissipate the river-flow energy to avoid longitudinal damage to the downstream river morphology. An optimal energy dissipator planning is essential to fulfilling safe specifications regarding flow behavior. This study aims to determine the variation of energy dissipators and evaluate its effect on the hydraulic jump and energy dissipation. For this purpose, a physical model was carried out on the existing weir condition (two steps). It was also carried out on four stepped-weir variations, i.e., three-step, three-step with additional baffle blocks at the end sills, four-step, and six-step. Dimensional analysis was employed to correlate the different parameters that affect the studied phenomenon. The study shows a three-step jump shows a significantly higher Lj/y1 ratio, which is an advantage to hydraulic jumps’ compaction. The comparison of energy dissipation in all weir variations shows that the three-stepped weir has wasted more energy than other types. The energy dissipation increase of the three-step type is 20.41% higher than the existing type’s energy dissipation and much higher than other types. The dimensions of the energy dissipation basin are the ratio of the width and height of the stairs (l/h) of the three-step type (2.50). Therefore, this type is more optimal to reduce the cavitation risk, which damages the river structure and downstream area.
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Bibliography

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ABDEL AAL G.M., SOBEAH M., HELAL E., EL-FOOLY M. 2018. Improving energy dissipation on stepped spillways using breakers. Ain Shams Engineering Journal. Vol. 9(4) p. 1887–1896. DOI 10.1016/j.asej.2017.01.008.

ALAM R.R.R., TAUFIQ M. 2018. Kajian hidrolika pelimpah samping pada model fisik Bendungan Pasuruhan Kabupaten Magelang Provinsi Jawa Tengah dengan Skala 1:60 [Study of side spillway hydraulics on physical model of Pasuruan Reservoir, Magelang Regency, Central Java Province with a scale of 1:60]. Art. of MSc Thesis. Water Engineering, Engineering Faculty – Brawijaya University p. 1–9.

ALTALIB A.N., MOHAMMED A.Y., HAYAWI H.A. 2019. Hydraulic jump and energy dissipation downstream stepped weir. Flow Measurement and Instrumentation. Vol. 69, 101616. DOI 10.1016/j.flowmea-sinst.2019.101616.

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Authors and Affiliations

Azmeri Azmeri
1
ORCID: ORCID
Hairul Basri
2
ORCID: ORCID
Alfiansyah Yulianur
1
ORCID: ORCID
Ziana Ziana
1
ORCID: ORCID
Faris Zahran Jemi
3
ORCID: ORCID
Ridha Aulia Rahmah
1

  1. Syiah Kuala University, Faculty of Engineering, Civil Engineering Department, Jl. Tgk. Syeh Abdul Rauf No. 7, Darussalam – Banda Aceh 23111, Indonesia
  2. Syiah Kuala University, Faculty of Agriculture, Department of Soil Science, Banda Aceh, Indonesia
  3. Syiah Kuala University, Faculty of Engineering, Department of Electrical Engineering, Banda Aceh, Indonesia
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Abstract

The article presents the results of experimental research aimed at recognizing the impact of the design of energy dissipation devices on the formation of bed local scouring below the sluice gate. The experiments were carried out on a model of a sluice gate built in a rectangular flume with a width of 0.58 m, with the outflow of the stream from under the slider to a horizontal bed 0.80 m long. Behind the dam gate valve three different constructions of energy dissipation devices were used: flat, horizontal slab, slab equipped with baffle blocks arranged in two rows and rip-rap. The experiments assumed forming a scour hole in 480 minutes downstream the sluice, where the bed was filled with sorted sand. The depths of the scour were measured in the longitudinal profile after 30, 60, 90, 120, 180, 240, 300, 360, 420 and 480 minutes. The deepest scour holes of the bed, both in terms of depth and length, occurred on the structure model with energy dissipation devices made as a flat, horizontal plate. At the same time, in this case, the hole was developing the most rapidly, and its shape and size posed the greatest threat to the stability of the structure. The use of baffle blocks arranged in two rows or a rip-rap behind the structure slide noticeably reduced the size of the scour and delayed the erosion of the bottom in time, as compared to the course of this process on a model with a flat, horizontal slab.

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Authors and Affiliations

Janusz Urbański
ORCID: ORCID
Marta Justyna Kiraga
Sławomir Bajkowski
ORCID: ORCID
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Abstract

The pattern of pore water pressure dissipation from the one-dimensional consolidation test significantly affects the calculated value of the coefficient of consolidation. This paper discusses the interpretation methodology for laboratory dissipation data from the oedometer test with the pore water pressure measurements or Rowe cell test. In the analysis, the gradient-based algorithm for finding the optimal value of the coefficient of consolidation is used against experimental results, obtained for various fine-grained soils. The appropriate value of coefficient of consolidation is considered as one with the lowest associated error function, which evaluates fitness between the experimental and theoretical dissipation curves. Based on the experimental results, two different patterns of the pore water pressure dissipation are identified, and the saturation of the specimen was found to be the key factor in describing the change in the patterns. For the monotonically decreasing dissipation curve, an inflection point is identified. The values of degree of dissipation at the inflection point are close to the theoretical value of 53.4%.
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Authors and Affiliations

Bartłomiej Szczepan Olek
1
ORCID: ORCID

  1. Krakow University of Technology, Faculty of Civil Engineering, Warszawska 24, 31-155 Kraków, Poland
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Abstract

To investigate the dynamic tensile properties and energy dissipation characteristics of marble in three different conditions: dry, water-saturated, and oil-saturated, a Brazilian disk splitting test was conducted using a 50 mm diameter Hopkinson pressure bar (SHPB) device. The findings indicate that the peak strain and dynamic tensile strength of the three conditions increase with strain rate, exhibiting a clear strain rate effect. Additionally, lubricating effects of water and oil weaken internal shear sliding friction, thus promoting crack expansion. Furthermore, immersion of fluid in marble weakens the cementation of internal mineral particles, leading to lower tensile strength of marble saturated with water and oil compared to dry marble under dynamic impact. When analyzing the energy dissipation of marble, both the absorption energy and dissipation energy density increase with oil strain rate, indicating a positive correlation. Moreover, numerical results obtained from ANSYS/LS-DYNA correspond well with experimental data, thus verifying and interpreting the experimental outcomes.
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Authors and Affiliations

Chaoxin Li
1
ORCID: ORCID
Dongyan Liu
2 3
Yunhui Zhu
4
ORCID: ORCID

  1. College of Architecture and Engineering, Chongqing University of Science and Technology, Chongqing401331, China
  2. Chongqing University, Chongqing 400000, China
  3. Chongqing College of Architecture and Technology, Chongqing 400000, China
  4. College of Architecture and Engineering, Chongqing University of Science and Technology, Chongqing 401331, China
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Abstract

This article analyzes the dynamic power losses generated by various hardware implementations of the BLAKE3 hash function. Estimations of the parameters were based on the results of post-route simulations of designs implemented in Xilinx Spartan-7 FPGAs. The algorithm was tested in various hardware organizations: based on a standard iterative architecture with one round instance in the programmable array, various derived versions with pipeline processing were elaborated, which ultimately led to a set of 6 architectural variants of the cipher, from the iterative case (without pipeline) to one with maximum of 6 pipeline stages. Moreover, the results obtained for the iterative architecture were compared with analogous implementations of the BLAKE2 (direct predecessor) and KECCAK (the foundation of the current SHA-3 standard) algorithms. This case study illustrates the differences (or lack thereof) in the power requirements of these three hash functions when they are implemented on an FPGA platform, and illustrate the significant savings that can be achieved by introducing pipeline to the processing of the BLAKE round.
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Authors and Affiliations

Jarosław Sugier
1

  1. Wrocław University of Science and Technology, Poland, Faculty of Information and Telecommunication Technology, Department of Computer Engineering, Poland
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Abstract

The scaling of turbulence characteristics such as turbulent fluctuation velocity, turbulent kinetic energy and turbulent energy dissipation rate was investigated in a mechanically agitated vessel 300 mm in inner diameter stirred by a Rushton turbine at high Reynolds numbers in the range 50 000 < Re < 100 000. The hydrodynamics and flow field was measured using 2-D TR PIV. The convective velocity formulas proposed by Antonia et al. (1980) and Van Doorn (1981) were tested. The turbulent energy dissipation rate estimated independently in both radial and axial directions using the one-dimensional approach was not found to be the same in each direction. Using the proposed correction, the values in both directions were found to be close to each other. The relation ε/(N3·D2) ∞ const. was not conclusively confirmed.

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Authors and Affiliations

Radek Šulc
Vít Pešava
Pavel Ditl
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Abstract

Feasibility of a model of gas bubble break-up and coalescence in an air-lift column enabling determination of bubble size distributions in a mixer with a self-aspirating impeller has been attempted in this paper. According to velocity measurements made by the PIV method with a self-aspirating impeller and Smagorinski’s model, the spatial distribution of turbulent energy dissipation rate close to the impeller was determined. This allowed to positively verify the dependence of gas bubble velocity used in the model, in relation to turbulent energy dissipation rate. Furthermore, the range of the eddy sizes capable of breaking up the gas bubbles was determined. The verified model was found to be greatly useful, but because of the simplifying assumptions some discrepancies of experimental and model results were observed.

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Authors and Affiliations

Jacek Stelmach
Czesław Kuncewicz
Radosław Musoski
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Abstract

A continuous contact layer exists between the top and bottom layer of concrete composite reinforced floors. The contact layer is characterised by linear elasticity and frictional properties. In this paper a model of single degree of freedom of composite floor is determined. The model assumes that the restoring forces and the non-conservative internal friction forces dissipating energy are produced within the contact layer. A hysteresis loop is created in the process of static loading and unloading of the model, with the energy absorption coefficient being defined on this basis. The value of the coefficient is rising along with the growing stiffness of the composite.

A critical damping ratio is a parameter describing free decaying vibration caused by non-conservative internal friction forces in the contact layer and in the bottom and top layer. The value of the ratio in the defined model is rising along with the lowering stiffness of the element representing contact layer.

The findings resulting from the theoretical analyses carried out, including the experimental tests, are the basis for the established methods of determining the concrete layer state for reinforced concrete floors. The method is based on energy dissipation in the contact layer.

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Authors and Affiliations

K. Gromysz
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Abstract

The article presents the problem of structural friction appearing in a screw joint with frictional effects between its elements. In the article, two mathematical models of screw joint are analysed. In the first model, high stiffness of a nut is assumed. In the second model, the influence of both cooperating elements (the screw and nut) is assumed.

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Authors and Affiliations

Wojciech Kaczmarek
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Abstract

The main points of the UPoN-2018 talk and some valuable comments from the Audience are briefly summarized. The talk surveyed the major issues with the notion of zero-point thermal noise in resistors and its visibility; moreover it gave some new arguments. The new arguments support the old view of Kleen that the known measurement data “showing” zero-point Johnson noise are instrumental artifacts caused by the energy-time uncertainty principle. We pointed out that, during the spectral analysis of blackbody radiation, another uncertainty principle is relevant, that is, the location-momentum uncertainty principle that causes only the widening of spectral lines instead of the zero-point noise artifact. This is the reason why the Planck formula is correctly confirmed by the blackbody radiation experiments. Finally a conjecture about the zero-point noise spectrum of wide-band amplifiers is shown, but that is yet to be tested experimentally.

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Authors and Affiliations

Laszlo B. Kish
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Abstract

This paper presents the research studies carried out on the application of lattice Boltzmann method (LBM) to computational aeroacoustics (CAA). The Navier-Stokes equation-based solver faces the difficulty of computational efficiency when it has to satisfy the high-order of accuracy and spectral resolution. LBM shows its capabilities in direct and indirect noise computations with superior space-time resolution. The combination of LBM with turbulence models also work very well for practical engineering machinery noise. The hybrid LBM decouples the discretization of physical space from the discretization of moment space, resulting in flexible mesh and adjustable time-marching. Moreover, new solving strategies and acoustic models are developed to further promote the application of LBM to CAA.

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Authors and Affiliations

Weidong Shao
Jun Li
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Abstract

One of the main causes of damage to weirs regulating the flow of water in canals is local erosion of the bottom and banks. This is mainly due to the excessive kinetic energy of the stream flow and the uneven volumetric distribution of the water flow rate at the end of the strengthening. Due to this, 35–40% of hydraulic structures fail prematurely. The aim of the research was to determine the parameters of the spatial hydraulic jump arising behind the hydrotechnical structure and the rapid expansion of the cross-section. The research showed that the hydraulic jump with a curved cylinder in the plan is a spatial form and not only dissipates the energy of the stream, but also acts as a diffuser. With the stream expansion angle values in the range of 7–10°, a highly turbulent flow remains, which still has high kinetic energy at a distance from the end of the structure. At an angle of 25–27°, the flow is smooth, the velocity distribution is uniform across the width of the channel. In some cases, the forced expansion of the cross-section at the outflow of the weir favours the energy dissipation and uniform flow velocity distribution.
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Authors and Affiliations

Zhuzbay Kassymbekov
1
Abai Shinibaev
1
Galimzhan Kassymbekov
1

  1. Satbayev University, Satpayev Str., 22, Almaty, 050013, Kazakhstan
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Abstract

This work aims to improve the total power dissipation, leakage currents and stability without disturbing the logic state of SRAM cell with concept called sub-threshold operation. Though, sub-threshold SRAM proves to be advantageous but fails with basic 6T SRAM cell during readability and writability. In this paper we have investigated a non-volatile 6T2M (6 Transistors & 2 Memristors) sub-threshold SRAM cell working at lower supply voltage of VDD=0.3V, where Memristor is used to store the information even at power failures and restores previous data with successful read and write operation overcomes the challenge faced. This paper also proposes a new configuration of non-volatile 6T2M (6 Transistors & 2 Memristors) subthreshold SRAM cell resulting in improved behaviour in terms of power, stability and leakage current where read and write power has improved by 40% and 90% respectively when compared to 6T2M (conventional) SRAM cell. The proposed 6T2M SRAM cell offers good stability of RSNM=65mV and WSNM=93mV which is much improved at low voltage when compared to conventional basic 6T SRAM cell, and improved leakage current of 4.92nA is achieved as compared.
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Authors and Affiliations

Zeba Mustaqueem
1
Abdul Quaiyum Ansari
1
Md Waseem Akram
1

  1. Jamia Milia Islamia Central University, India
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Abstract

Shape memory polymers (SMP) are new multifunctional materials raising increasing interest in various functional applications. Among them, polyurethane shape memory polymers (PU-SMP) are particularly attractive due to their combination of shape memory, high strength and biocompatible properties. Developing new applications for PU-SMP requires comprehensive research on their characteristics. This work involved investigating the structure and mechanical behavior as well as characterizing the energy storage and dissipation of a thermoplastic PU-SMP with a glass transition temperature (Tg) of 25_C during tensile loading-unloading. The process of energy storage and dissipation in the PU-SMP was investigated based on the stress-strain curves recorded by a quasi-static testing machine and the temperature changes, accompanying the deformation process, obtained by using a fast and sensitive infrared camera. The results showed that the thermomechanical behavior of the examined PU-SMP depends significantly on the strain rate. At a higher strain rate, there are higher stress and related temperature changes, which lead to greater energy dissipation. However, the energy storage values estimated during the deformation process turned out to be not significant, indicating that the work supplied to the PU-SMP structure during loading is mainly converted into heat. It should also be noted that the structural investigation revealed no crystalline phase in the investigated PU-SMP.
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Authors and Affiliations

Maria Staszczak
1
ORCID: ORCID
Arkadiusz Gradys
2
ORCID: ORCID
Karol Golasiński
1
ORCID: ORCID
Elżbieta A. Pieczyska
1
ORCID: ORCID

  1. Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawi´nskiego 5B, 02-106 Warsaw, Poland
  2. Multidisciplinary Research Center, Cardinal Stefan Wyszy´ nski University in Warsaw, Dewajtis 5, 01-815 Warsaw, Poland
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Abstract

In this research, nonlinear analysis of composite shear walls (CSWs) with a gap between reinforced concrete wall and steel frame is investigated under cyclic loading by the use of the finite element method (FEM) software ABAQUS. For the purpose of the verification, an experimental test is modelled and comparison of its obtained result with that of the experimental test demonstrates an inconsiderable difference between them; therefore, the reasonable accuracy of the modelling is revealed. Then, effects of different parameters on the behaviour of the CSWs are examined. Gap size between reinforced concrete wall and steel frame, reinforcement percentage, steel sections of beams and columns, and existence of reinforced concrete wall are considered as parameters. It is concluded that change of the parameters affects the ultimate strength, ductility, and energy dissipation of the system. A steel shear wall (SSW) is also modelled and compared with the CSWs. Buckling of the walls is presented as well.

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Authors and Affiliations

Alireza Bahrami
Mojtaba Yavari
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Abstract

Steel-glulam structure is a new type of composite structure,glulam have lateral support effect on steel plate, that can prevent premature buckling of steel plate and improve the stability of steel structure. In order to study the influence of column’s cross-section form on the seismic performance of steel-glulam composite beam-to-column exterior joint, the column’s cross-section form was taken as the basic variable (glulam rectangular section , H-beam section and H-beam-glulam rectangular section were used respectively). The pseudo-static tests of three composite beam-to-column joints were carried out to observe the different failure modes, and obtain the mechanical performance indexes. The experiment results demonstrated that: The energy dissipation capacity of beam-to-column exterior joint composed of glulam column was the worst, the ultimate bearing capacity and stiffness were the lowest. The ultimate bearing capacity of the exterior joints formed by the H-beam column and the H-beam-glulam composite column were both high, and their ductility coefficients were similar, while the former had better energy dissipation capacity.
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Authors and Affiliations

Shaowei Duan
1
Xinglong Liu
2
Jian Yuan
1
Zhifeng Wang
1

  1. Central South University of Forestry and Technology, College of Civil Engineering, Changsha, Hunan, China
  2. Shenzhen Huayang International Design Group Co., Ltd. Changsha Branch, Changsha, Hunan, China
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Abstract

The self-centering buckling-restrained brace (SC-BRB) may achieve self-restoration for structures and, to a certain degree, diminish the substantial seismic residual deformation following rare earthquakes when compared to the usage of the conventional buckling-restrained brace (BRB). It may be possible to reduce the abrupt change in stiffness at the location of the strengthened stories and make the outrigger better at dissipating energy by improving the design of the energy-dissipation outrigger. This study compares the seismic performances of two types of energy-dissipation outriggers with BRB and SC-BRB web member designs during rare earthquakes so that the changes can be measured. The results show that using the SC-BRB web member design reduces the maximum inter-story drift ratio by an average of 7.68% and increases the average plastic-energy dissipation of the outrigger truss by 8.75%. The evaluation results showthat the SC-BRB outrigger truss structure has better structural regularity and energy-dissipation performance. It has the ability to efficiently regulate the structural seismic response and lessen primary-structure damage.
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Authors and Affiliations

Yongxu Jin
1
ORCID: ORCID
Man Xu
1
ORCID: ORCID
Jie Jia
1
ORCID: ORCID

  1. College of Civil Engineering, Northeast Forestry University, Harbin 150040, China
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Abstract

The purpose of the study was to estimate in 2012 range and degree of soil contamination due to local diesel fuel leakage spills that occurred in 1980 and from any subsequent activities in the vicinity of the scientific Polish Polar Station in Hornsund, Svalbard. The area of the study covered the immediate vicinity of station buildings including areas of the 1980’s fuel barrel storage depot and location of current fuel tanks. Results of the study were compared with a similar study performed in 1980. As of 2012, areas potentially contaminated covered 0.9 ha, which was a 50% decrease compared to 1980. The area contaminated with total petroleum hydrocarbons was extremely localized. Spread of petroleum hydrocarbons from 1980’s source of pollution investigated 32 years later showed that petroleum derived products were environmentally mobile. Concentrations of total petroleum hydrocarbons in surface soils of the unsaturated active layer above the permafrost decreased significantly mostly due to surface runoff and dispersion through ephemeral drainages. Concentrations of total petroleum hydrocarbons increased with depth through time in sandy soils on the flat area where the largest 1980’s fuel barrel depot was located.

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Authors and Affiliations

Anna J. Krzyszowska Waitkus
Brian Waitkus

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