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Journal Article 9

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2021 2

2020 2

2019 1

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Asymmetric Genetic Algorithm 1

Connections 1

Fatigue 1

Resin-injected bolts 1

S-N curves 1

Structural adhesives 1

Structural reinforcements 1

adaptive 1

benefit and cost analysis (BCA) 1

constraints of serviceability limits 1

constraints of ultimate load 1

cracked structure 1

drought 1

ecosystem dis-services (EDS) 1

ecosystem services (ES) 1

edge-based strain smoothing 1

extremum seeking (ES) 1

fractional calculus 1

fractional order control (FOC) 1

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Adaptive selective ES-FEM limit analysis of cracked plane-strain structures

H. NGUYEN-XUAN,T. RABCZUK

Frontiers of Structural and Civil Engineering 2015, Volume 9, Issue 4,   Pages 478-490 doi: 10.1007/s11709-015-0317-7

Abstract: This paper presents a simple and efficient approach for predicting the plastic limit loads in cracked plane-strain structures. We use two levels of mesh repartitioning for the finite element limit analysis. The master level handles an adaptive primal-mesh process through a dissipation-based indicator. The slave level performs the subdivision of each triangle into three sub-triangles and constitutes a dual mesh from a pair of two adjacent sub-triangles shared by common edges of the primal mesh. Applying a strain smoothing projection to the strain rates on the dual mesh, the incompressibility constraint and the flow rule constraint are imposed over the edge-based smoothing domains and everywhere in the problem domain. The limit analysis problem is recast into the compact form of a second-order cone programming (SOCP) for the purpose of exploiting interior-point solvers. The present method retains a low number of optimization variables. It offers a convenient way for designing and solving the large-scale optimization problems effectively. Several benchmark examples are given to show the simplicity and effectiveness of the present method.

Keywords： cracked structure     limit analysis     von Mises criterion     edge-based strain smoothing     second-order cone programming     adaptive    

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Evaluation of a novel Asymmetric Genetic Algorithm to optimize the structural design of 3D regular and irregular steel frames

Mohammad Sadegh ES-HAGHI, Aydin SHISHEGARAN, Timon RABCZUK

Frontiers of Structural and Civil Engineering 2020, Volume 14, Issue 5,   Pages 1110-1130 doi: 10.1007/s11709-020-0643-2

Abstract: We propose a new algorithm, named Asymmetric Genetic Algorithm (AGA), for solving optimization problems of steel frames. The AGA consists of a developed penalty function, which helps to find the best generation of the population. The objective function is to minimize the weight of the whole steel structure under the constraint of ultimate loads defined for structural steel buildings by the American Institute of Steel Construction (AISC). Design variables are the cross-sectional areas of elements (beams and columns) that are selected from the sets of side-flange shape steel sections provided by the AISC. The finite element method (FEM) is utilized for analyzing the behavior of steel frames. A 15-storey three-bay steel planar frame is optimized by AGA in this study, which was previously optimized by algorithms such as Particle Swarm Optimization (PSO), Particle Swarm Optimizer with Passive Congregation (PSOPC), Particle Swarm Ant Colony Optimization (HPSACO), Imperialist Competitive Algorithm (ICA), and Charged System Search (CSS). The results of AGA such as total weight of the structure and number of analyses are compared with the results of these algorithms. AGA performs better in comparison to these algorithms with respect to total weight and number of analyses. In addition, five numerical examples are optimized by AGA, Genetic Algorithm (GA), and optimization modules of SAP2000, and the results of them are compared. The results show that AGA can decrease the time of analyses, the number of analyses, and the total weight of the structure. AGA decreases the total weight of regular and irregular steel frame about 11.1% and 26.4% in comparing with the optimized results of SAP2000, respectively.

Keywords： optimization     steel frame     Asymmetric Genetic Algorithm     constraints of ultimate load     constraints of serviceability limits     penalty function    

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Signal promoting role of a p-type transition metal dichalcogenide used for the detection of ultra-trace amounts of diclofenac via a labeled aptasensor

Abdolhamid Hatefi-Mehrjardi, Amirkhosro Beheshti-Marnani, Zarrin Es'haghi

Frontiers of Chemical Science and Engineering 2019, Volume 13, Issue 4,   Pages 823-831 doi: 10.1007/s11705-019-1797-0

Abstract: A -type transition metal dichalcogenide (WS ) was synthesized and hybridized with graphene oxide via a simple hydrothermal method. The as-prepared material was used to modify a glassy carbon electrode for the fabrication of a simple, stable, and repeatable methylene blue-labeled “signal-off” aptasensor used for the sensitive determination of very low amounts of sodium diclofenac (DCF). The synthetic material, modification process, and role of WS in the current response enhancement were studied by X-ray diffraction, energy-dispersive X-ray spectroscopy, field emission scanning electron microscopy, high resolution transmission electron microscopy, Hall effect, cyclic voltammetry, differential pulse voltammetry, and electrochemical impedance spectroscopy. Subsequently, a wide linear range of DCF concentration (0.5–300 nmol/L), very low limit of detection (0.23 nmol/L), and good selectivity were obtained using the differential pulse voltammetry method with the assembled aptasensor. Finally, the fabricated aptasensor was successfully developed for physiological real samples with significant recoveries.

Keywords： labeled aptasensor     transition metal dichalcogenide     graphene oxide     sodium diclofenac    

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Ecosystem service tradeoff between traditional and modern agriculture: a case study in Congjiang County, Guizhou Province, China

Dan ZHANG, Qingwen MIN, Moucheng LIU, Shengkui CHENG

Frontiers of Environmental Science & Engineering 2012, Volume 6, Issue 5,   Pages 743-752 doi: 10.1007/s11783-011-0385-4

Abstract: Besides crops, agriculture supplies all three major categories of ecosystem services (ES).The flows of ES and EDS are directly dependent on the management of agricultural ecosystems.method of Chinese agriculture, which supports sustainable agriculture, has been proven to increase ESIn this study, an investigation was conducted on the ecosystem services (ES) and ecosystem dis-servicesAfterwards, the economic values of ES and EDS were quantified experimentally and calculated based on

Keywords： agriculture     rice-fish agriculture     rice monoculture     benefit and cost analysis (BCA)     ecosystem services (ES    

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Restoring soil health to reduce irrigation demand and buffer the impacts of drought

MORREALE, Zhigang LI, Erin MENZIES PLUER, Kirsten KURTZ, Xilu NI, Cuiping WANG, Changxiao LI, Harold VAN ES

Frontiers of Agricultural Science and Engineering 2020, Volume 7, Issue 3,   Pages 339-346 doi: 10.15302/J-FASE-2020348

Abstract:

Irrigation consumes three quarters of global water withdrawals each year. Strategies are needed to reduce irrigation water use, including increasing the efficiency of transfer methods and field application. Comprehensive restoration of soil health, specifically through organic matter amendments, can substantially reduce irrigation demand and increase crop yield. A program to restore severely degraded and desertified soils by incorporating coarse woodchips into the soil successfully increased rainfall capture and elevated soil moisture for several weeks between rainfall events at both Ningxia, north-west China and North Dakota, USA. With addition of fertilizer, woodchip incorporation further increased growth of wheat and alfalfa. Comprehensive soil health assessment of remnant grasslands was used to develop target reference soil profiles by which to guide restoration efforts. Given that most agricultural soils are degraded to some degree, soil health restoration can provide a powerful strategy toward achieving global food and water security.

Keywords： drought     irrigation     restoration     soil health     woodchips    

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Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Ammar NEÇAIBIA,Samir LADACI,Abdelfatah CHAREF,Jean Jacques LOISEAU

Frontiers in Energy 2015, Volume 9, Issue 1,   Pages 43-53 doi: 10.1007/s11708-014-0343-5

Abstract: The proposed control scheme was based on extremum-seeking (ES) combined with fractional order systems

Keywords： extremum seeking (ES)     fractional order control (FOC)     fractional calculus     photovoltaic (PV) panel     maximum    

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A cooperative heterogeneous vehicular clustering framework for efficiency improvement Research Articles

Ahmed, Umm-e-Habiba, Naveed Akram, Fausto Pedro García Márquez,ify_ia@yahoo.com,faustopedro.garcia@uclm.es

Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 9,   Pages 1247-1259 doi: 10.1631/FITEE.2000260

Abstract: Heterogeneous ing integrates multiple types of communication networks to work efficiently for various vehicular applications. One popular form of heterogeneous network is the integration of long-term evolution (LTE) and dedicated short-range communication. The of such a network infrastructure and the non- involved in sharing cost/data are potential problems to solve. A ing framework is one solution to these problems, but the framework should be formally verified and validated before being deployed in the real world. To solve these issues, first, we present a heterogeneous framework, named destination and interest-aware clustering, for ing that integrates vehicular ad hoc networks with the LTE network for improving road traffic efficiency. Then, we specify a model system of the proposed framework. The model is formally verified to evaluate its performance at the functional level using a model checking technique. To evaluate the performance of the proposed framework at the micro-level, a heterogeneous simulation environment is created by integrating state-of-the-art tools. The comparison of the simulation results with those of other known approaches shows that our proposed framework performs better.

Keywords： 车辆集群；异构性；协同；形式验证；系统模型    

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Spatial fading channel emulation for over-the-air testing of millimeter-wave radios: concepts and experimental validations

Wei Fan, Lassi Hentilä, Pekka Kyösti,wfa@es.aau.dk

Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 4,   Pages 548-559 doi: 10.1631/FITEE.2000484

Abstract: Millimeter-wave (mmWave) communication is regarded as the key enabling component for fifth-generation (5G) cellular systems due to the large available spectrum bandwidth. To make mmWave new radio (NR) a reality, tremendous efforts have been exerted from the industry and academia. Performance evaluation of mmWave NR is a mandatory step and the key to ensuring the success of mmWave 5G deployment. Over-the-air (OTA) radiated method of testing mmWave NR in laboratory conditions is highly attractive, since it facilitates virtual field testing of mmWave devices in realistic propagation conditions. In this paper, we first discuss the need for and challenges in OTA measurement of mmWave 5G NR under fading channel conditions. After that, two promising candidate solutions, i.e., wireless cable and multi-probe anechoic chamber (MPAC), are detailed. Their principles, applicability for mmWave NR, and main challenges are discussed. Furthermore, preliminary experimental validation results in a frequency range 2 anechoic chamber are demonstrated for the wireless cable and MPAC methods at 28 GHz.

Keywords： 空间信道模型；空口测试；无线线缆；多探头电波暗室；FR2验证    

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Fatigue Strength Evaluation of Resin-Injected Bolted Connections Using Statistical Analysis

Silva Rebelo, Rui Artur Bartólo Calçada, Luís Alberto Proença Simões

Engineering 2017, Volume 3, Issue 6,   Pages 795-805 doi: 10.1016/j.eng.2017.12.001

Abstract:

Different strategies can be used to perform reparations and reinforcements of ancient bolted and riveted metallic bridges. As the riveting process is not currently a common practice, it requires proper equipment and skilled workers. Another solution is the use of welding. However, the weldability of old steels is poor. Bolts are very attractive alternative solutions, and are most commonly used to repair old metallic bridges. Fitted bolts are expensive solutions; the alternative is the use of resin-injected bolts. The behavior of bolted joints with preloaded resin-injected bolts has been studied using quasi-static and creep tests; however, few studies on the slip and fatigue behavior of these joints can be found in the literature. This paper presents an overview of a few experimental programs that were carried out by several authors aiming at evaluating the fatigue behavior of single and double shear resin-injected bolted connections. A comparison between the experimental data of joints with preloaded standard bolts and preloaded resininjected bolts shows a fatigue strength reduction in the latter. Since Eurocode 3 (EC3) suggests the same fatigue strength curve for joints made of resin-injected bolts and standard bolts, this may raise some concerns. Furthermore, research on the feasibility of using both bonded and bolted connections is shown. This last study was performed with high-strength low-alloy structural steel plates and an acrylic structural adhesive for metal bonding. For both case studies, a statistical analysis is performed on fatigue experimental data using linearized boundaries and the Castillo and Fernández-Canteli model. Fatigue design curves are proposed and compared with the design suggestions of several European and North American standards.

Keywords： Fatigue     Connections     Structural reinforcements     Structural adhesives     S-N curves     Resin-injected bolts    

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Title Author Date Type Operation

Adaptive selective ES-FEM limit analysis of cracked plane-strain structures

H. NGUYEN-XUAN,T. RABCZUK

Journal Article

Evaluation of a novel Asymmetric Genetic Algorithm to optimize the structural design of 3D regular and irregular steel frames

Mohammad Sadegh ES-HAGHI, Aydin SHISHEGARAN, Timon RABCZUK

Journal Article

Signal promoting role of a p-type transition metal dichalcogenide used for the detection of ultra-trace amounts of diclofenac via a labeled aptasensor

Abdolhamid Hatefi-Mehrjardi, Amirkhosro Beheshti-Marnani, Zarrin Es'haghi

Journal Article

Ecosystem service tradeoff between traditional and modern agriculture: a case study in Congjiang County, Guizhou Province, China

Dan ZHANG, Qingwen MIN, Moucheng LIU, Shengkui CHENG

Journal Article

Restoring soil health to reduce irrigation demand and buffer the impacts of drought

MORREALE, Zhigang LI, Erin MENZIES PLUER, Kirsten KURTZ, Xilu NI, Cuiping WANG, Changxiao LI, Harold VAN ES

Journal Article

Fractional order extremum seeking approach for maximum power point tracking of photovoltaic panels

Ammar NEÇAIBIA,Samir LADACI,Abdelfatah CHAREF,Jean Jacques LOISEAU

Journal Article

A cooperative heterogeneous vehicular clustering framework for efficiency improvement

Ahmed, Umm-e-Habiba, Naveed Akram, Fausto Pedro García Márquez,ify_ia@yahoo.com,faustopedro.garcia@uclm.es

Journal Article

Spatial fading channel emulation for over-the-air testing of millimeter-wave radios: concepts and experimental validations

Wei Fan, Lassi Hentilä, Pekka Kyösti,wfa@es.aau.dk

Journal Article

Fatigue Strength Evaluation of Resin-Injected Bolted Connections Using Statistical Analysis

Silva Rebelo, Rui Artur Bartólo Calçada, Luís Alberto Proença Simões

Journal Article