Search results for: site response analysis

Authors: Wenxue Xu

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Fluid resistance damper is an important damping element to attenuate vehicle vibration. It converts vibration energy into thermal energy dissipation through oil throttling. It is a typical fluid-solid-heat coupling problem. A complete three-dimensional flow-structure-thermal coupling dynamics simulation model of a gas-filled fluid-resistance damper was established. The flow-condition-based interpolation (FCBI) method and direct coupling calculation method, the unit's FCBI-C fluid numerical analysis method and iterative coupling calculation method are used to achieve the damper dynamic response of the piston rod under sinusoidal excitation; the air chamber inflation pressure, spring compression characteristics, constant flow passage cross-sectional area and oil parameters, etc. The system parameters, excitation frequency, and amplitude and other excitation parameters are analyzed and compared in detail for the effects of differential pressure characteristics, velocity characteristics, flow characteristics and dynamic response of valve opening, floating piston response and piston rod output force characteristics. Experiments were carried out on some simulation analysis conditions. The results show that the node-based FCBI (flow-condition-based interpolation) fluid numerical analysis method and direct coupling calculation method can better guarantee the conservation of flow field calculation, and the calculation step is larger, but the memory is also larger; if the chamber inflation pressure is too low, the damper will become cavitation. The inflation pressure will cause the speed characteristic hysteresis to increase, and the sealing requirements are too strict. The spring compression characteristics have a great influence on the damping characteristics of the damper, and reasonable damping characteristic needs to properly design the spring compression characteristics; the larger the cross-sectional area of the constant flow channel, the smaller the maximum output force, but the more stable when the valve plate is opening.

Keywords: damper, fluid-structure-thermal coupling, heat generation, heat transfer

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Authors: Frederic Jumelle, Kelvin So, Didan Deng

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A method and system for neuropsychological performance test, comprising a mobile terminal, used to interact with a cloud server which stores user information and is logged into by the user through the terminal device; the user information is directly accessed through the terminal device and is processed by artificial neural network, and the user information comprises user facial emotions information, performance test answers information and user chronometrics. This assessment is used to evaluate the cognitive performance and emotional response of the subject to a series of dichotomous questions describing various situations of daily life and challenging the users' knowledge, values, ethics, and principles. In industrial applications, the timing of this assessment will depend on the users' need to obtain a service from a provider, such as opening a bank account, getting a mortgage or an insurance policy, authenticating clearance at work, or securing online payments.

Keywords: artificial intelligence, neurofinance, neuropsychology, risk management

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Authors: Mohamed M. El Gendy, Ibrahim A. El Arabi, Rafeek W. Abdel-Missih, Omar A. Kandil

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Nonlinear analysis is one of the most important design and safety tools in structural engineering. Based on the finite-element method, a geometrical and material nonlinear analysis of large span reinforced concrete arches is carried out considering soil-structure interaction. The concrete section details and reinforcement distribution are taken into account. The behavior of soil is considered via Winkler's and continuum models. A computer program (NARC II) is specially developed in order to follow the structural behavior of large span reinforced concrete arches up to failure. The results obtained by the proposed model are compared with available literature for verification. This work confirmed that the geometrical and material nonlinearities, as well as soil structure interaction, have considerable influence on the structural response of reinforced concrete arches.

Keywords: nonlinear analysis, reinforced concrete arched structure, soil-structure interaction, geotechnical engineering

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Authors: Daniele Losanno, Giorgio Serino

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This paper focuses on parametric analysis of reinforced concrete structures equipped with supplemental damping braces. Practitioners still luck sufficient data for current design of damper added structures and often reduce the real model to a pure damper braced structure even if this assumption is neither realistic nor conservative. In the present study, the damping brace is modelled as made by a linear supporting brace connected in series with the viscous/hysteretic damper. Deformation capacity of existing structures is usually not adequate to undergo the design earthquake. In spite of this, additional dampers could be introduced strongly limiting structural damage to acceptable values, or in some cases, reducing frame response to elastic behavior. This work is aimed at providing useful considerations for retrofit of existing buildings by means of supplemental damping braces. The study explicitly takes into consideration variability of (a) relative frame to supporting brace stiffness, (b) dampers’ coefficient (viscous coefficient or yielding force) and (c) non-linear frame behavior. Non-linear time history analysis has been run to account for both dampers’ behavior and non-linear plastic hinges modelled by Pivot hysteretic type. Parametric analysis based on previous studies on SDOF or MDOF linear frames provide reference values for nearly optimal damping systems design. With respect to bare frame configuration, seismic response of the damper-added frame is strongly improved, limiting deformations to acceptable values far below ultimate capacity. Results of the analysis also demonstrated the beneficial effect of stiffer supporting braces, thus highlighting inadequacy of simplified pure damper models. At the same time, the effect of variable damping coefficient and yielding force has to be treated as an optimization problem.

Keywords: brace stiffness, dissipative braces, non-linear analysis, plastic hinges, reinforced concrete frames

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Authors: Justine A. Lloyd

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Since the onset of the Syrian Civil War in 2011, the ancient city of Dura-Europos has faced widespread destruction and looting. The site is one of many places in the country the terrorist group ISIS has specifically targeted, allegedly due to its particular representations of Syrian history and culture. However, looted art and artifacts are the extremist group’s second largest source of income, only after oil. The protection of this site is important to both academics and the millions who have called Syria a home, as it aids in the nation’s sense of identity, reveals developments in the arts, and contributes to humanity’s collective history. At a time when Syria’s culture is being flattened, this sense of cultural expression is especially important to maintain. Creating an awareness of the magnitude of the issue at hand begins with an examination of the rich history of the ancient fortress city. Located on the western bank of the Euphrates River, Dura-Europos contains artifacts dating back to the Hellenistic, Parthian, and Roman periods. Though a great deal of the art and artifacts have remained safe in institutions such as the National Museum of Damascus and the Yale University Art Gallery, hundreds of looting pits and use of heavy machinery on the site has severely set back the investigative progress made by archaeologists over the last century, as well as the prospect of future excavation. Further research draws on the current destruction of the site by both ISIS and opportunists involved with the black market. Because Dura-Europos is located in a war stricken region, the acquisition of data and possibility of immediate action is particularly challenging. Resources gained from local reports, in addition to technology such as satellite imagery, however, have provided a firm starting point for the evaluation of the state of the site. The Syrian Ministry of Culture, UNESCO, and numerous Syrian and global organizations provide insight into the historic city’s past, present issues, and future plans to ensure that the cultural integrity of the site is upheld. Though over seventy percent of Dura-Europos has been completely decimated, this research challenges the notion that physically destroyed sites are lost forever. This paper assesses preventative measures that can take place to ensure the preservation of the site’s art and architecture, including examining possible solutions to the damage, such as digital reconstruction, replication, and distribution of information through exhibitions and other forms of publically accessible information. In order to investigate any possible retribution, research also includes the necessary information pertaining the global laws and regulations dealing with cultural heritage, as it directly affects the ways in which this situation can be dealt with. With the countless experts and citizens dedicated to the importance of cultural heritage, the prospect of honoring and valuing elements of Dura-Europos is possible—whether physically preserved or otherwise.

Keywords: antiquities law, archaeological sites, restitution, Syrian Civil War

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Authors: Kangujam Monika, Kiranbala Devi Thokchom, Soibam Sandhyarani Devi

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Earthquake is a major natural hazard in India. Manipur, located in the North-Eastern Region of India, is one of the most affected location in the region prone to earthquakes since it lies in an area where Indian and Eurasian tectonic plates meet and is in seismic Zone V which is the most severe intensity zone, according to IS Code. Some recent earthquakes recorded in Manipur are M 6.7 epicenter at Tamenglong (January 4, 2016), M 5.2 epicenter at Churachandpur (February 24, 2017) and most recent M 4.4 epicenter at Thoubal (June 19, 2017). In these recent earthquakes, some houses and buildings were damaged, landslides were also occurred. A field study was carried out. An overview of the various causal factors involved in triggering of earthquake in Manipur has been discussed. It is found that improper planning, poor design, negligence, structural irregularities, poor quality materials, construction of foundation without proper site soil investigation and non-implementation of remedial measures, etc., are possibly the main causal factors for damage in Manipur during earthquake. The study also suggests, though the proper design of structure and foundation along with soil investigation, ground improvement methods, use of modern techniques of construction, counseling with engineer, mass awareness, etc., might be effective solution to control the hazard in many locations. An overview on the analysis pertaining to earthquake in Manipur together with on-going detailed site specific geotechnical investigation were presented.

Keywords: Manipur, earthquake, hazard, structure, soil

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Authors: Neetu Tyagi, Sumit Sharma

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The study illustrates the results of an integrated study done on Tangni landslide located on NH-58 at Chamoli, Uttarakhand. Geological, geo-morphological and geotechnical investigations were carried out to understand the mechanism of landslide and to plan further investigation and monitoring. At any rate, the movements were favored by continuous rainfall water infiltration from the zones where the phyllites/slates and Dolomites outcrop. The site investigations were carried out including the monitoring of landslide movements and of the water level fluctuations due to rainfall give us a better understanding of landslide dynamics that have been causing in time soil instability at Tangni landslide site. The Early Warning System (EWS) installed different types of sensors and all sensors were directly connected to data logger and raw data transfer to the Defence Terrain Research Laboratory (DTRL) server room with the help of File Transfer Protocol (FTP). The slip surfaces were found at depths ranging from 8 to 10 m from Geophysical survey and hence sensors were installed to the depth of 15m at various locations of landslide. Rainfall is the main triggering factor of landslide. In this study, the developed model of unsaturated soil slope stability is carried out. The analysis of sensors data available for one year, indicated the sliding surface of landslide at depth between 6 to 12m with total displacement up to 6cm per year recorded at the body of landslide. The aim of this study is to set the threshold and generate early warning. Local peoples already alert towards landslide, if they have any types of warning system.

Keywords: early warning system, file transfer protocol, geo-morphological, geotechnical, landslide

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Authors: Li Na Zhao, Arieh Warshel

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The design of enzymes is an extremely challenging task, and this is also true for metalloenzymes. In the case of naturally evolved enzymes, one may consider the active site residues as the musicians in the enzyme orchestra, while the metal can be considered as their concertmaster. Together they catalyze reactions as if they performed a masterpiece written by nature. The Lactonase can be thought as a member of the amidohydrolase family, with two concertmasters, Fe and Zn, at its active site. It catalyzes the quorum sensing signal- N-acyl homoserine lactones (AHLs or N-AHLs)- by hydrolyzing the lactone ring. This process, known as quorum quenching, provides a strategy in the treatment of infectious diseases without introducing selection pressure. However, the activity of lactonase is metal-dependent, and this dependence hampers the clinic usage. In our study, we use the empirical valence bond (EVB) approach to evaluate the catalytic contributions decomposing them to electrostatic and other components.

Keywords: enzyme redesign, empirical valence bond, lactonase, quorum quenching

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Authors: Asma Alhuqail, Nagwa Aref

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Programmed cell death resembles a real nature active defense in Datura metel against TMV after three days of virus infection. Physiological plant response was assessed for asymptomatic healthy and symptomatic infected detached leaves. The results indicated H2O2 and Chlorophyll-a as the most potential parameters. Chlorophyll-a was considered the only significant predictor variant for the H2O2 dependent variant with a P value of 0.001 and R-square of 0.900. The plant immune response was measured within three days of virus infection using the cutoff value of H2O2 (61.095 lmol/100 mg) and (63.201 units) for the tail moment in the Comet Assay. Their percentage changes were 255.12% and 522.40% respectively which reflects the stress of virus infection in the plant. Moreover, H2O2 showed 100% specificity and sensitivity in the symptomatic infected group using the receiver-operating characteristic (ROC). All tested parameters in the symptomatic infected group had significant correlations with twenty-five positive and thirty-one negative correlations where the P value was <0.05 and 0.01. Chlorophyll-a parameter had a crucial role of highly significant correlation between total protein and salicylic acid. Contrarily, this correlation with tail moment unit was (r = _0.930, P <0.01) where the P value was < 0.01. The strongest significant negative correlation was between Chlorophyll-a and H2O2 at P < 0.01, while moderate negative significant correlation was seen for Chlorophyll-b where the P value < 0.05. The present study discloses the secret of the three days of rapid transient production of activated oxygen species (AOS) that was enough for having potential quantitative physiological parameters for defensive plant response toward the virus.

Keywords: programmed cell death, plant–adaptive immune response, hydrogen peroxide (H2O2), physiological parameters

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Authors: N. Musayeva, N. Rustamova, N. Bagirov, S. Ibadov

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Purpose: to analyze the long-term results of external dacryocystorhinostomy (DCR), which remains the preferred primary procedure in the surgical treatment of lacrimal duct obstruction in chronic dacryocystitis. Methodology: long-term results of external DCR (after 3 years) performed on 90 patients (90 eyes) with chronic dacryocystitis from 2018 to 2020 were evaluated. The Azerbaijan National Center of Ophthalmology, named after acad. Zarifa Aliyeva. 15 of the patients were men, 75 – women. The average age was 45±3.2 years. Surgical operations were performed under local anesthesia. All patients suffered from diabetes mellitus for more than 3 years. All patients underwent external DCR and silicone drainage (tube) was implanted. In the postoperative period (after 3 years), lacrimation, purulent discharge, and the condition of the scar at the operation site were assessed. Results: All patients were under observation for more than 18 months. In general, the effectiveness of the surgical operation was 93.34%. Recurrence of disease was observed in 6 patients and in 3 patients (3.33%), the scar at the site of the operation was rough (non-cosmetic). In 3 patients (3.33%) – the surgically formed anastomosis between the lacrimal sac and the nasal bone was obstructed by scar tissue. These patients were reoperated by trans canalicular laser DCR. Conclusion: Despite the long-term (more than a hundred years) use of external DCR, it remains one of the primary techniques in the surgery of chronic dacryocystitis. Due to the high success rate and good long-term results of DCR in the treatment of chronic dacryocystitis in patients suffering from diabetes mellitus, we recommend external DCR for this group of patients.

Keywords: chronic dacryocystitis, diabetes mellitus, external dacryocystorhinostomy, long-term results

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Authors: Mohammad Javad Zehtab, S. Alireza Mirghasemi, Ali Majlesara, Parvin Tajik, Babak Siavashi

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Objective: There are different modalities proposed for tennis elbow treatment with few randomized trials comparing them. We designed a study to compare the effectiveness of five different modalities and determine the usefulness of recently proposed extensor grip test (EGT) in predicting the response to treatment. Methods: In a randomized controlled clinical trial 92 of 98 tennis elbow patients in Sina hospital of Tehran, Iran between 2006 and 2007 fulfill trial entry criteria, among these patients 56 (60.9%) had positive EGT result. Stratified on EGT result, patients allocated randomly to 5 treatment groups: Brace (B) group, physiotherapy (P), brace + physiotherapy (BP), injection (I) and injection + physiotherapy (IP). Results: Patients who had positive result of EGT had better response to treatments: less SOC (p = 0.06), less PFFQ and patients’ satisfaction scores (p < 0.001). Among the treatment IP was the most successful, then BP, P and B, respectively; injection was the worst treatment modality. Response to treatment was comparable in all groups between EGT positive and negative patients except bracing; in which positive EGT was correlated with a dramatic response to treatment. Conclusion: In all patients IP and then BP is recommended but in EGT negatives, bracing seems to be of no use. Injection alone is not recommended in either group.

Keywords: tennis elbow, extensor grip test, physiotherapy, tennis elbow treatment

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Authors: Mohsen Sanayei, Jerzy Szpunar

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The present study investigates the effects of deformation strain and annealing temperature on the formation of twin boundaries, deformation and recrystallization texture evolution and grain boundary networks and connectivity. The resulting microstructures were characterized using Electron Backscatter Diffraction (EBSD) and X-Ray Diffraction (XRD) both immediately following small amount of deformation and after short time annealing at high temperature to correlate the micro and macro texture evolution of these alloys. Furthermore, this study showed that the process of grain boundary engineering, consisting cycles of deformation and annealing, is found to substantially reduce the mass and size of random boundaries and increase the proportion of low Coincidence Site Lattice (CSL) grain boundaries.

Keywords: coincidence site lattice, grain boundary engineering, electron backscatter diffraction, texture, x-ray diffraction

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Authors: Eun Gyeong Lee, Ji Young Park, Hyun Ae Woo

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Reactive oxygen species (ROS) production is involved in ischemia/reperfusion (I/R) injury in kidney of mice. Oxidative stress develops from an imbalance between ROS production and reduced antioxidant defenses. Many enzymatic and nonenzymatic antioxidant systems including peroxiredoxins (Prxs) are present in kidney to maintain an appropriate level of ROS and prevent oxidative damage. Prxs are a family of peroxidases that reduce peroxides, with a conserved cysteine residue serving as the site of oxidation by peroxides. In this study, we examined the protective role of Prx V against I/R-induced acute kidney injury (AKI) using Prx V wild type (WT) and knockout (KO) mice. We compared the response of Prx V WT and KO mice in mice model of I/R injury. Renal structure, functions, oxidative stress markers, protein levels of oxidative damage marker were worse in Prx V KO mice. Ablation of Prx V enhanced susceptibility to I/R-induced oxidative stress. Prx V KO mice were seen to have more severe renal damage than Prx V WT mice in mice model of I/R injury. Our results demonstrate that Prx V is protective against I/R-induced AKI.

Keywords: peroxiredoxin, ischemia/reperfusion, kidney, oxidative stress

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Authors: Abdelhammid Chibane

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Often, for architectural reasons or designs, several buildings have a non-uniform profile in elevation. Depending on the configuration of the construction and the arrangements structural elements, the non-uniform profile in elevation (the recess) is considered concept of a combination of non-uniform distributions of strength, stiffness, weight and geometry along the height of irregular structures. Therefore, this type of configuration can induce irregular distribution load causing a serious concentration stresses at the discontinuity. This therefore requires a serious behavioral treatment buildings in an earthquake. If appropriate measures are not taken into account, structural irregularity may become a major source of damage during earthquakesEarth. In the past, several research investigations have identified differences in dynamic response of irregular and regular porches. Among the most notable differences are the increments of displacements and ductility applications in floors located above the level of the shoulder and an increase in the contribution of the higher modes cisaillement1 efforts, ..., 10. The para -ssismiques codes recommend the methods of analysis Dynamic (or modal history) to establish the forces of calculation instead of the static method equivalent, which is basically applicable only to regular structures without major discontinuities in the mass, rigidity and strength along the height 11, 12 .To investigate the effects of irregular profiles on the structures, the main objective of this study was the assessment of the inelastic response, in terms of applications of ductility four types of non-uniform multi-stage structures subjected to relatively severe earthquakes. In the This study, only the parallel responses are analyzed setback.

Keywords: buildings, concentration stresses, ductility, ductility, designs, irregular structures

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Authors: G. A. Khalid, M. D. Jones, R. Prabhu, A. Mason-Jones, W. Whittington, H. Bakhtiarydavijani, P. S. Theobald

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Head injury in childhood is a common cause of death or permanent disability from injury. However, despite its frequency and significance, there is little understanding of how a child’s head responds during injurious loading. Whilst Infant Post Mortem Human Subject (PMHS) experimentation is a logical approach to understand injury biomechanics, it is the authors’ opinion that a lack of subject availability is hindering potential progress. Computer modelling adds great value when considering adult populations; however, its potential remains largely untapped for infant surrogates. The complexities of child growth and development, which result in age dependent changes in anatomy, geometry and physical response characteristics, present new challenges for computational simulation. Further geometric challenges are presented by the intricate infant cranial bones, which are separated by sutures and fontanelles and demonstrate a visible fibre orientation. This study presents an FE model of a newborn infant’s head, developed from high-resolution computer tomography scans, informed by published tissue material properties. To mimic the fibre orientation of immature cranial bone, anisotropic properties were applied to the FE cranial bone model, with elastic moduli representing the bone response both parallel and perpendicular to the fibre orientation. Biofiedility of the computational model was confirmed by global validation against published PMHS data, by replicating experimental impact tests with a series of computational simulations, in terms of head kinematic responses. Numerical results confirm that the FE head model’s mechanical response is in favourable agreement with the PMHS drop test results.

Keywords: finite element analysis, impact simulation, infant head trauma, material properties, post mortem human subjects

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Authors: A. Chellil, A. Nour, S. Lecheb, H.Mechakra, A. Bouderba, H. Kebir

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In this paper, the numerical study for the instability of a composite rotor is presented, under dynamic loading response in the harmonic analysis condition. The analysis of the stress which operates the rotor is done. Calculations of different energies and the virtual work of the aerodynamic loads from the rotor is developed. The use of the composite material for the rotor, offers a good Stability. Numerical calculations on the model develop of three dimensions prove that the damage effect has a negative effect on the stability of the rotor. The study of the composite rotor in transient system allowed to determine the vibratory responses due to various excitations.

Keywords: rotor, composite, damage, finite element, numerical

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Authors: J. Ranjbarn, A. Alibeigloo

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In this paper, we present an analytical method for analysis of nano-scale spherical shell subjected to thermo-mechanical shocks based on nonlocal elasticity theory. Thermo-mechanical properties of nano shpere is assumed to be temperature dependent. Governing partial differential equation of motion is solved analytically by using Laplace transform for time domain and power series for spacial domain. The results in Laplace domain is transferred to time domain by employing the fast inverse Laplace transform (FLIT) method. Accuracy of present approach is assessed by comparing the the numerical results with the results of published work in literature. Furtheremore, the effects of non-local parameter and wall thickness on the dynamic characteristics of the nano-sphere are studied.

Keywords: nano-scale spherical shell, nonlocal elasticity theory, thermomechanical shock, dynamic response

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Authors: P. Suchismita Behera, V. G. Sathe, A. K. Nigam, P. A. Bhobe

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Co-existence of long-range ferromagnetism and semi-conductivity with correlated behavior of structural, magnetic, optical and electrical properties in various sites doping at CdCr2Se4 makes it a most promising candidate for spin-based electronic applications and magnetic devices. It orders ferromagnetically below TC = 130 K with a direct band gap of ~ 1.5 eV. The magnetic ordering is believed to result from strong competition between the direct antiferromagnetic Cr-Cr spin couplings and the ferromagnetic Cr-Se-Cr exchange interactions. With an aim of understanding the influence of crystal structure on its magnetic properties without disturbing the magnetic site, we investigated four compositions with 3%, 5%, 7% and 10% of Sn-substitution at Cd-site. Partial substitution of Cd2+ (0.78Å) by small sized nonmagnetic ion, Sn4+ (0.55Å), is expected to bring about local lattice distortion as well as a change in electronic charge distribution. The structural disorder would affect the Cd/Sn – Se bonds thus affecting the Cr-Cr and Cr-Se-Cr bonds. Whereas, the charge imbalance created due to Sn4+ substitution at Cd2+ leads to the possibility of Cr mixed valence state. Our investigation of the local crystal structure using the EXAFS, Raman spectroscopy and magnetic properties using SQUID magnetometry of the Cd1-xSnxCr2Se4 series reflects this premise. All compositions maintain the Fd3m cubic symmetry with tetrahedral distribution of Sn at Cd-site, as confirmed by XRD analysis. Lattice parameters were determined from the Rietveld refinement technique of the XRD data and further confirmed from the EXAFS spectra recorded at Cr K-edge. Presence of five Raman-active phonon vibrational modes viz. (T2g (1), T2g (2), T2g (3), Eg, A1g) in the Raman spectra further confirms the crystal symmetry. Temperature dependence of the Raman data provides interesting insight to the spin– phonon coupling, known to dominate the magneto-capacitive properties in the parent compound. Below the magnetic ordering temperature, the longitudinal damping of Eg mode associated with Se-Cd/Sn-Se bending and T2g (2) mode associated to Cr-Se-Cr interaction, show interesting deviations with respect to increase in Sn substitution. Besides providing the estimate of TC, the magnetic measurements recorded as a function of field provide the values of total magnetic moment for all the studied compositions indicative of formation of multiple Cr valences.

Keywords: exchange interactions, EXAFS, ferromagnetism, Raman spectroscopy, spinel chalcogenides

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Authors: Bel G Raggad

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An e-Learning setting is a distributed computing environment where information resources can be connected to any public network. Public networks are very unsecure which can compromise the reliability of an e-Learning environment. This study is only concerned with the intrusion detection aspect of e-Learning security and how incident responses are planned. The literature reported great advances in intrusion detection system (ids) but neglected to study an important ids weakness: suspected events are detected but an intrusion is not determined because it is not defined in ids databases. We propose an incident response generator (DIRG) that produces incident responses when the working ids system suspects an event that does not correspond to a known intrusion. Data involved in intrusion detection when ample uncertainty is present is often not suitable to formal statistical models including Bayesian. We instead adopt Dempster and Shafer theory to process intrusion data for the unknown event. The DIRG engine transforms data into a belief structure using incident scenarios deduced by the security administrator. Belief values associated with various incident scenarios are then derived and evaluated to choose the most appropriate scenario for which an automatic incident response is generated. This article provides a numerical example demonstrating the working of the DIRG system.

Keywords: decision support system, distributed computing, e-Learning security, incident response, intrusion detection, security risk, statefull inspection

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Authors: Xiaohua Zou, Yongxin Su

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The reasonable operation of heating, ventilation, and air conditioning (HVAC) is of great significance in improving the security, stability, and economy of power system operation. However, the uncertainty of the operating environment, thermal comfort varies by users and rapid decision-making pose challenges for HVAC demand response optimization. In this regard, this paper proposes a reinforcement learning-based method for HVAC demand response optimization considering few-shot personalized thermal comfort (PTC). First, an HVAC DR optimization framework based on few-shot PTC model and DRL is designed, in which the output of few-shot PTC model is regarded as the input of DRL. Then, a few-shot PTC model that distinguishes between awake and asleep states is established, which has excellent engineering usability. Next, based on soft actor criticism, an HVAC DR optimization algorithm considering the user’s PTC is designed to deal with uncertainty and make decisions rapidly. Experiment results show that the proposed method can efficiently obtain use’s PTC temperature, reduce energy cost while ensuring user’s PTC, and achieve rapid decision-making under uncertainty.

Keywords: HVAC, few-shot personalized thermal comfort, deep reinforcement learning, demand response

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Authors: Chong-Yang Qiao

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Mobile augmented reality (MAR) tracking targets from the surroundings and aids operators for interactive data and procedures visualization, potential equipment and system understandably. Operators remotely communicate and coordinate with each other for the continuous tasks, information and data exchange between control room and work-site. In the routine work, distributed control system (DCS) monitoring and work-site manipulation require operators interact in real-time manners. The critical question is the improvement of user experience in cooperative works through applying Augmented Reality in the traditional industrial field. The purpose of this exploratory study is to find the cognitive model for the multiple task performance by MAR. In particular, the focus will be on the comparison between different tasks and environment factors which influence information processing. Three experiments use interface and interaction design, the content of start-up, maintenance and stop embedded in the mobile application. With the evaluation criteria of time demands and human errors, and analysis of the mental process and the behavior action during the multiple tasks, heuristic evaluation was used to find the operators performance with different situation factors, and record the information processing in recognition, interpretation, judgment and reasoning. The research will find the functional properties of MAR and constrain the development of the cognitive model. Conclusions can be drawn that suggest MAR is easy to use and useful for operators in the remote collaborative works.

Keywords: mobile augmented reality, remote collaboration, user experience, cognition model

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Authors: H. Sakamoto, Y. Nakagawara, S. Oguri

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Drought stress is a critical environmental factor that adversely affects crop productivity and quality. Because of their immobile nature, plants have evolved mechanisms to sense and respond to drought stress. We identified a novel locus of Arabidopsis, designated DRA1 (drought responsive ankyrin 1), whose disruption leads to increased drought stress tolerance. DRA1 encodes a transmembrane protein with an ankyrin repeat motif that has been implicated in diverse cellular processes such as signal transduction. RT-PCR analysis revealed that there were at least two splicing variants of DRA1 transcripts in wild type plants. In response to drought stress, the levels of DRA1 transcripts retaining second and third introns were increased, whereas these introns were removed under unstressed conditions. These results suggest that DRA1 protein may negatively regulate plant drought tolerance and that the expression of DRA1 is regulated in response to drought stress by alternative splicing.

Keywords: alternative splicing, ankyrin repeat, Arabidopsis, drought tolerance

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Authors: Oindrila Nath, S. Sridharan

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Long-term (2002-2012) temperature and ozone measurements by Sounding of Atmosphere by Broadband Emission Radiometry (SABER) instrument onboard Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) satellite zonally averaged over 10°N-15°N are used to study their long-term changes and their responses to solar cycle, quasi-biennial oscillation and El Nino Southern Oscillation. The region is selected to provide more accurate long-term trends and variabilities, which were not possible earlier with lidar measurements over Gadanki (13.5°N, 79.2°E), which are limited to cloud-free nights, whereas continuous data sets of SABER temperature and ozone are available. Regression analysis of temperature shows a cooling trend of 0.5K/decade in the stratosphere and that of 3K/decade in the mesosphere. Ozone shows a statistically significant decreasing trend of 1.3 ppmv per decade in the mesosphere although there is a small positive trend in stratosphere at 25 km. Other than this no significant ozone trend is observed in stratosphere. Negative ozone-QBO response (0.02ppmv/QBO), positive ozone-solar cycle (0.91ppmv/100SFU) and negative response to ENSO (0.51ppmv/SOI) have been found more in mesosphere whereas positive ozone response to ENSO (0.23ppmv/SOI) is pronounced in stratosphere (20-30 km). The temperature response to solar cycle is more positive (3.74K/100SFU) in the upper mesosphere and its response to ENSO is negative around 80 km and positive around 90-100 km and its response to QBO is insignificant at most of the heights. Composite monthly mean of ozone volume mixing ratio shows maximum values during pre-monsoon and post-monsoon season in middle stratosphere (25-30 km) and in upper mesosphere (85-95 km) around 10 ppmv. Composite monthly mean of temperature shows semi-annual variation with large values (~250-260 K) in equinox months and less values in solstice months in upper stratosphere and lower mesosphere (40-55 km) whereas the SAO becomes weaker above 55 km. The semi-annual variation again appears at 80-90 km, with large values in spring equinox and winter months. In the upper mesosphere (90-100 km), less temperature (~170-190 K) prevails in all the months except during September, when the temperature is slightly more. The height profiles of amplitudes of semi-annual and annual oscillations in ozone show maximum values of 6 ppmv and 2.5 ppmv respectively in upper mesosphere (80-100 km), whereas SAO and AO in temperature show maximum values of 5.8 K and 4.6 K in lower and middle mesosphere around 60-85 km. The phase profiles of both SAO and AO show downward progressions. These results are being compared with long-term lidar temperature measurements over Gadanki (13.5°N, 79.2°E) and the results obtained will be presented during the meeting.

Keywords: trends, QBO, solar cycle, ENSO, ozone, temperature

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Authors: Cherifi Katia, Al-Hawat Marie-Lynn, Tricou Leo-Paul, Lamontagne Stephanie, Tran Minh, Ngu Amy Ching Yie, Manrique Gabriela, Guirguis Natalie, Machuca Parra Arturo Israel, Matoori Simon

Abstract:

Diabetic foot ulcers (DFUs) are a serious and prevalent complication of diabetes. Current diagnostic options are limited to macroscopic wound analysis such as wound size, depth, and infection. Molecular diagnostics promise to improve DFU diagnosis, staging, and assessment of treatment response. Here, we developed a rapid and easy-to-use fluorescent pH-sensing bandage for wound diagnostics. In a fluorescent dye screen, we identified pyranine as the lead compound due to its suitable pH-sensing properties in the clinically relevant pH range of 6 to 9. To minimize the release of this dye into the wound bed, we screened a library of ionic microparticles and found a strong adhesion of the anionic dye to a cationic polymeric microparticle. These dye-loaded microparticles showed a strong fluorescence response in the clinically relevant pH range of 6 to 9 and a dye release below 1% after one day in biological media. The dye-loaded microparticles were subsequently encapsulated in a calcium alginate hydrogel to minimize the interaction of the microparticles with the wound tissue. This pH-sensing diagnostic wound dressing was tested on full-thickness dorsal wounds of mice, and a linear fluorescence response (R2 = 0.9909) to clinically relevant pH values was observed. These findings encourage further development of this pH-sensing system for molecular diagnostics in DFUs.

Keywords: wound ph, fluorescence, diagnostics, diabetic foot ulcer, wound healing, chronic wounds, diabetes

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Authors: Pallavi N., Gayatri Jadhav

Abstract:

Good quality water is of prime importance for a healthy living. Fluoride is one such mineral present in water which causes many health problems in humans and specially children. Fluoride is said to be a double edge sword because lesser and higher concentration of fluoride in drinking water can cause both dental and skeletal fluorosis. Fluoride is one of the important mineral usually present at a higher concentration in ground water. There are many researches being carried out for defluoridation method. In the present research, fluoride removal is demonstrated using banana peel which is a biowaste as a biocoagulant. Response Surface Methodology (RSM) is a statistical design tool which is used to design the experiment. Central Composite Design (CCD) was used to determine the influence of the pH and dosage of the coagulant on the optimal removal of fluoride from a simulated water sample. 895 of fluoride removal were obtained in a acidic pH range of 4 – 9 and bio coagulant dosage of dosage of 18 – 20mg/L.

Keywords: Fluoride, Response Surface Methodology, Dosage, banana peel

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Authors: Wen-Juinn Chen, Yi-Phei Chou, Jou-Han Wang

Abstract:

Tainan coast is suffering from beach erosion, wave overtopping, and lowland flooding; though most of the shoreline has been protected by seawalls, they still threatened by sea level rise. For coastal resources developing, coastal land utilization, and to draft an appropriate mitigate strategy. Firstly; we must assess the impact of beach erosion under a different scenario of climate change. Here, we have used the meteorological data since 1898 to 2012 to prove that the Tainan area did suffer the impact of climate change. The result shows the temperature has been raised to about 1.7 degrees since 1989. Also, we analyzed the tidal data near the Tainan coast (Anpin site and Junjunn site), it shows sea level rising with a rate about 4.1~4.8 mm/year, this phenomenon will have serious impacts on Tainan coastal area, especially it will worsen coastal erosion. So we have used Bruun rule to calculate the shoreline retreated rate at every two decade period since 2012. Wave data and bottom sand diameter D50 were used to calculate the closure depth that will be used in Bruun formula and the active length of the profile is computed by the beach slope and Dean's equilibrium concept. After analysis, we found that in 2020, the shoreline will be retreated about 3.0 to 12 meters. The maximum retreat is happening at Chigu coast. In 2060, average shoreline retreated distance is 22m, but at Chigu and Tsenwen, shoreline may be backward retreat about 70m and will be reached about 130m at 2100, this will cause a lot of coastal land loss to the sea, protect and mitigate project must be quickly performed.

Keywords: sea level rise, shoreline, coastal erosion, climate change

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Authors: Nabeel M. Alikunhi, Zenon B. Batang, Aymen Charef, Abdulaziz M. Al-Suwailem

Abstract:

Saudi Arabia has a long history of using traps as a traditional fishing gear for catching commercially important demersal, mainly coral reef-associated fish species. Fish traps constitute the dominant small-scale fisheries in Saudi waters of Arabian Gulf (eastern seaboard of Saudi Arabia). Recently, however, traps have been increasingly used along the Saudi Red Sea coast (western seaboard), with a coastline of 1800 km (71%) compared to only 720 km (29%) in the Saudi Gulf region. The production trend for traps indicates a recent increase in catches and percent contribution to traditional fishery landings, thus ascertaining the rapid proliferation of trap fishing along the Saudi Red Sea coast. Reef-associated fish species, mainly groupers (Serranidae), emperors (Lethrinidae), parrotfishes (Scaridae), scads and trevallies (Carangidae), and snappers (Lutjanidae), dominate the trap catches, reflecting the reef-dominated shelf zone in the Red Sea. This ongoing investigation covers following major objectives (i) Baseline studies to characterize trap fishery through landing site visit and interview surveys (ii) Stock assessment by fisheries and biological data obtained through monthly landing site monitoring using fishery operational model by FLBEIA, (iii) Operational impacts, derelict traps assessment and by-catch analysis through bottom-mounted video camera and onboard monitoring (iv) Elucidation of fishing grounds and derelict traps impacts by onboard monitoring, Remotely Operated underwater Vehicle and Autonomous Underwater Vehicle surveys; and (v) Analysis of gear design and operations which covers colonization and deterioration experiments. The progress of this investigation on the impacts of the trap fishery on fish stocks and the marine environment in the Saudi Red Sea region is presented.

Keywords: red sea, Saudi Arabia, fish trap, stock assessment, environmental impacts

Procedia PDF Downloads 334

Authors: Cihat Aşan

Abstract:

Istanbul Strait is a crucial and narrow waterway, not only having a role in linking two continents but also has a crossover mission for the petroleum, which is the biggest energy resource, between its supply and demand sources. Besides its substantial features, sensitivities like around 18 million populations in surroundings, military facilities, ports, oil lay down areas etc. also brings the high risk to use of Istanbul Strait. Based on the statistics of Turkish Ministry of Transportation, Maritime and Communication, although the number of vessel passage in Istanbul Strait is declining, tonnage of hazardous and flammable cargo like oil and chemical transportation is increasing and subsequently the risk of oil pollution, loss of life and property is also rising. Based on the mentioned above; it is crucial to be prepared for the initial and subsequent response to eventual ship sourced oil spill which may cause to block the Strait for an unbearable duration. In this study; preconditioned Istanbul Strait sensitive areas studies has been taken into account and possible oil spill scenario is loaded to PISCES 2 (Potential Incident Simulation Control and Evaluation System) decision support system for the determined specific sea area. Consequences of the simulation like oil expanding process, required number and types of assets to response, had in hand and evaluated.

Keywords: Istanbul strait, oil spill, PISCES simulator, initial response

Procedia PDF Downloads 322

Authors: Fouad. Inel, Lakhdar. Khochemane

Abstract:

This article presents a comparative response specification performance between two controllers of three and four cable based robots for various applications. The main objective of this work is: The first is to use the direct and inverse geometric model to study and simulate the end effector position of the robot with three and four cables. A graphical user interface has been implemented in order to visualizing the position of the robot. Secondly, we present the determination of static and dynamic tensions and lengths of cables required to flow different trajectories. At the end, we study the response of our systems in closed loop with a Proportional-Integrated Derivative (PID) and Proportional-Integrated (PD) controllers then this last are compared the results of the same examples using MATLAB/Simulink; we found that the PID method gives the better performance, such as rapidly speed response, settling time, compared to PD controller.

Keywords: parallel cable-based robots, geometric modeling, dynamic modeling, graphical user interface, open loop, PID/PD controllers

Procedia PDF Downloads 430

Authors: Youssouf Benmeriem

Abstract:

Shear strength of sandy soils has been considered as the important parameter to study the stability of different civil engineering structures when subjected to monotonic, cyclic and earthquake loading conditions. The proposed research investigated the effect of grading characteristics on the shear strength and mechanical behavior of granular classes of sands mixed with silt in loose and dense states (Dr = 15% and 90%). The laboratory investigation aimed at understanding the extent or degree at which shear strength of sand-silt mixture soil is affected by its gradation under static loading conditions. For the purpose of clarifying and evaluating the shear strength characteristics of sandy soils, a series of Casagrande shear box tests were carried out on different reconstituted samples of sand-silt mixtures with various gradations. The soil samples were tested under different normal stresses (100, 200 and 300 kPa). The results from this laboratory investigation were used to develop insight into the shear strength response of sand and sand-silt mixtures under monotonic loading conditions. The analysis of the obtained data revealed that the grading characteristics (D10, D50, Cu, ESR, and MGSR) have significant influence on the shear strength response. It was found that shear strength can be correlated to the grading characteristics for the sand-silt mixture. The effective size ratio (ESR) and mean grain size ratio (MGSR) appear as pertinent parameters to predict the shear strength response of the sand-silt mixtures for soil gradation under study.

Keywords: grading characteristics, granular classes of sands, mechanical behavior, sand-silt, shear strength

Procedia PDF Downloads 369