Search results for: shock labelling

Authors: Vishwajit Ghatge, David Looper

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Over the last few decades, oilfield service rolling equipment has significantly increased in weight, primarily because of emissions regulations, which require larger/heavier engines, larger cooling systems, and emissions after-treatment systems, in some cases, etc. Larger engines cause more vibration and shock loads, leading to failure of electronics and control systems. If the vibrating frequency of the engine matches the system frequency, high resonance is observed on structural parts and mounts. One such existing automated control equipment system comprising wire rope mounts used for mounting computers was designed approximately 12 years ago. This includes the use of an industrial- grade computer to control the system operation. The original computer had a smaller, lighter enclosure. After a few years, a newer computer version was introduced, which was 10 lbm heavier. Some failures of internal computer parts have been documented for cases in which the old mounts were used. Because of the added weight, there is a possibility of having the two brackets impact each other under off-road conditions, which causes a high shock input to the computer parts. This added failure mode requires validating the existing mount design to suit the new heavy-weight computer. This paper discusses the modal finite element method (FEM) analysis and experimental modal analysis conducted to study the effects of vibration on the wire rope mounts and the computer. The existing mount was modelled in ANSYS software, and resultant mode shapes and frequencies were obtained. The experimental modal analysis was conducted, and actual frequency responses were observed and recorded. Results clearly revealed that at resonance frequency, the brackets were colliding and potentially causing damage to computer parts. To solve this issue, spring mounts of different stiffness were modeled in ANSYS software, and the resonant frequency was determined. Increasing the stiffness of the system increased the resonant frequency zone away from the frequency window at which the engine showed heavy vibrations or resonance. After multiple iterations in ANSYS software, the stiffness of the spring mount was finalized, which was again experimentally validated.

Keywords: experimental modal analysis, FEM Modal Analysis, frequency, modal analysis, resonance, vibration

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Authors: Tomás Speziale

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This paper aims to analyse how Ian Hacking states the theoretical basis of his research on the classification of people. Although all his early philosophical education had been based in Foucault, it is also true that Erving Goffman’s perspective provided him with epistemological and methodological tools for understanding face-to-face relationships. Hence, all his works must be thought of as social science texts that combine the research on how the individuals are constituted ‘top-down’ (as in Foucault), with the inquiry into how people renegotiate ‘bottom-up’ the classifications about them. Thus, Hacking´s proposal constitutes a middle ground between the French Philosopher and the American Sociologist. Placing himself between both authors allows Hacking to build a frame that is expected to adjust to Social Sciences’ main particularity: the fact that they study interactive kinds. These are kinds of people, which imply that those who are classified can change in certain ways that prompt the need for changing previous classifications themselves. It is all about the interaction between the labelling of people and the people who are classified. Consequently, understanding the way in which Hacking uses Foucault’s and Goffman’s theories is essential to fully comprehend the social dynamic between individuals and concepts, what Bert Hansen had called dialectical realism. His theoretical proposal, therefore, is not only valuable because it combines diverse perspectives, but also because it constitutes an utterly original and relevant framework for Sociological theory and particularly for Criminology.

Keywords: classification of people, Foucault's archaeology, Goffman's interpersonal sociology, interactive kinds

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Authors: Bartosz Olszanski, Zbigniew Nosal, Jacek Rokicki

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An experimental study of cold-jet (nitrogen) reaction control jet system has been carried out to investigate the flow control efficiency for low to moderate jet pressure ratios (total jet pressure p0jet over free stream static pressure in the wind tunnel p∞) and different angles of attack for infinite Mach number equal to 2. An investigation of jet influence was conducted on a flat plate geometry placed in the test section of intermittent supersonic wind tunnel of Department of Aerodynamics, WUT. Various convergent jet nozzle geometries to obtain different jet momentum ratios were tested on the same test model geometry. Surface static pressure measurements, Schlieren flow visualizations (using continuous and photoflash light source), load cell measurements gave insight into the supersonic crossflow interaction for different jet pressure and jet momentum ratios and their influence on the efficiency of side jet control as described by the amplification factor (actual to theoretical net force generated by the control nozzle). Moreover, the quasi-steady numerical simulations of flow through the same wind tunnel geometry (convergent-divergent nozzle plus test section) were performed using ANSYS Fluent basing on Reynolds-Averaged Navier-Stokes (RANS) solver incorporated with k-ω Shear Stress Transport (SST) turbulence model to assess the possible spurious influence of test section walls over the jet exit near field area of interest. The strong bow shock, barrel shock, and Mach disk as well as lambda separation region in front of nozzle were observed as images taken by high-speed camera examine the interaction of the jet and the free stream. In addition, the development of large-scale vortex structures (counter-rotating vortex pair) was detected. The history of complex static pressure pattern on the plate was recorded and compared to the force measurement data as well as numerical simulation data. The analysis of the obtained results, especially in the wake of the jet showed important features of the interaction mechanisms between the lateral jet and the flow field.

Keywords: flow visualization techniques, pressure measurements, reaction control jet, supersonic cross flow

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Authors: Prataksitorn Chonlakan, Tiparat Wongsilarat

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The traditional clinical practice guideline used at the emergency room at Songkhla Hospital in caring for patients who come in contact with jellyfish venom took a long time for the pain to reduce to the level that patients can cope with. To investigate the effectiveness of clinical practice guidelines by comparing the effectiveness of a newly developed clinical practice guideline with the traditional clinical practice guideline in the following aspects: 1) pain reduction, 2) length of pain, 3) the rate of patient’s re-visit, 4) the rate of severe complications such as anaphylactic shock, and cardiac arrest, and death, and 5) patient satisfaction. This study employed a quasi-experimental research design. Thirty subjects were selected with purposive sampling from jellyfish-sting patients who came for treatment at the Emergency Room of Songkhla Hospital. The subjects were divided using random assignment into two groups of 15 each: an experimental group, and the control group. The control group was treated using the traditional clinical practice guideline consisting of rinsing the affected area with 0.9% normal saline, using a cloth soaked with vinegar to press against the affected area, and controlling pain using tramadol or diclofenac intramuscular injection. The data were analyzed using descriptive statistics and paired t-test at the significance level p < 0.05. The results of the study revealed the following. The pain level in the experimental group was significantly lower than that of the control group (the average pain score of the experimental group was 3.46 while that of the control group was 6.33) (p < 0.05).The length of pain in the experimental group was significantly lower than that of the control group (the average length of pain in the experimental group was 48.67 minutes while that of the control group was 105.35 minutes) (p < 0.05). The rate of re-visit within 12 hours in the experimental group was significantly lower than that of the control group (the rate of re-visit within 12 hours of the experimental group was 0.07 while that of the control group was 0.00) (p < 0.05).No severe complications such as anaphylactic shock, and cardiac arrest were found in the two groups of subjects.The rate of satisfaction among the subjects in the experimental group was significantly higher than that of the control group (the rate of satisfaction among the subjects of the experimental group was 90.00 percent while that among the control group was 66.33 percent) (p < 0.05). The newly develop clinical practice guideline could reduce pain and increase satisfaction among jellyfish-sting patients better than the traditional clinical practice guideline.

Keywords: effectiveness, clinical practice guideline, jellyfish-sting patients, cardiac arrest

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Authors: Temitope O. Tokosi

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Healthcare is a human right. The sensitivity of health issues has necessitated the introduction of Enterprise Content Management (ECM) at district hospitals in the Western Cape Province of South Africa. The objective is understanding clinicians’ perception of ECM at their workplace. It is a descriptive case study design of constructivist paradigm. It employed a phenomenological data analysis method using a pattern matching deductive based analytical procedure. Purposive and s4nowball sampling techniques were applied in selecting participants. Clinicians expressed concerns and frustrations using ECM such as, non-integration with other hospital systems. Inadequate access points to ECM. Incorrect labelling of notes and bar-coding causes more time wasted in finding information. System features and/or functions (such as search and edit) are not possible. Hospital management and clinicians are not constantly interacting and discussing. Information turnaround time is unacceptably lengthy. Resolving these problems would involve a positive working relationship between hospital management and clinicians. In addition, prioritising the problems faced by clinicians in relation to relevance can ensure problem-solving in order to meet clinicians’ expectations and hospitals’ objective. Clinicians’ perception should invoke attention from hospital management with regards technology use. The study’s results can be generalised across clinician groupings exposed to ECM at various district hospitals because of professional and hospital homogeneity.

Keywords: clinician, electronic content management, hospital, perception, technology

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Authors: João Boaventura Branco De Matos

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Currently, in Brazil, there is a considerable collection of publications on the supplementary health sector, but the vast majority is limited to retrospective examination of the sector. The present contribution starts from the diagnosis of an overwhelming change in the role of the State and its institutions, as well as an accelerated and no less forceful change in the way of producing goods and services, resulting in a clash between these different waves (state and market). This shock produces unique energy, capable of imposing major changes in the most varied sectors. Based on this diagnosis, there was an opportunity to offer the perspective and propositional study of regulatory measures relevant to the best conduct and performance of this sector in the future.

Keywords: private health regulation, state and market, forecasts in Brazilian regulation, political economy

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Authors: Olfa Kaabia, Ilyes Abid, Khaled Guesmi

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This pioneer paper studies whether and how Bitcoin shocks are transmitted to the U.S economy. We employ a new methodology: TVP FAVAR model with stochastic volatility. We use a large dataset of 111 major U.S variables from 1959:m1 to 2016:m12. The results show that Bitcoin shocks significantly impact the U.S. economy. This significant impact is pronounced in a volatile and increasing U.S economy. The Bitcoin has a positive relationship on the U.S real activity, and a negative one on U.S prices and interest rates. Effects on the Monetary Policy exist via the inter-est rates and the Money, Credit and Finance transmission channels.

Keywords: bitcoin, US economy, FAVAR models, stochastic volatility

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Authors: Sumit Roy, A. Uddin

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One of the significant reasons that increase the delay time in the intersections at heterogeneous traffic condition is a sudden reduction of the capacity of the roads. In this study, the delay for this sudden capacity reduction is estimated. Two intersections at Dhaka city were brought in to thestudy, i.e., Kakrail intersection, and SAARC Foara intersection. At Kakrail intersection, the sudden reduction of capacity in the roads is seen at three downstream legs of the intersection, which are because of slowing down or stopping of buses for loading and unloading of passengers. At SAARC Foara intersection, sudden reduction of capacity was seen at two downstream legs. At one leg, it was due to loading and unloading of buses, and at another leg, it was for both loading and unloading of buses and reduction of the number of lanes. With these considerations, the delay due to intentional stoppage or slowing down of buses and reduction of the number of lanes for these two intersections are estimated. Here the delay was calculated by two approaches. The first approach came from the concept of shock waves in traffic streams. Here the delay was calculated by determining the flow, density, and speed before and after the sudden capacity reduction. The second approach came from the deterministic analysis of queues. Here the delay is calculated by determining the volume, capacity and reduced capacity of the road. After determining the delay from these two approaches, the results were compared. For this study, the video of each of the two intersections was recorded for one hour at the evening peak. Necessary geometric data were also taken to determine speed, flow, and density, etc. parameters. The delay was calculated for one hour with one-hour data at both intersections. In case of Kakrail intersection, the per hour delay for Kakrail circle leg was 5.79, and 7.15 minutes, for Shantinagar cross intersection leg they were 13.02 and 15.65 minutes, and for Paltan T intersection leg, they were 3 and 1.3 minutes for 1st and 2nd approaches respectively. In the case of SAARC Foara intersection, the delay at Shahbag leg was only due to intentional stopping or slowing down of busses, which were 3.2 and 3 minutes respectively for both approaches. For the Karwan Bazar leg, the delays for buses by both approaches were 5 and 7.5 minutes respectively, and for reduction of the number of lanes, the delays for both approaches were 2 and 1.78 minutes respectively. Measuring the delay per hour for the Kakrail leg at Kakrail circle, it is seen that, with consideration of the first approach of delay estimation, the intentional stoppage and lowering of speed by buses contribute to 26.24% of total delay at Kakrail circle. If the loading and unloading of buses at intersection is made forbidden near intersection, and any other measures for loading and unloading of passengers are established far enough from the intersections, then the delay at intersections can be reduced at significant scale, and the performance of the intersections can be enhanced.

Keywords: delay, deterministic queue analysis, shock wave, passenger loading-unloading

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Authors: B.Shukir, H.Woo, P.Barzo, D.Kis

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Preoperative brain mapping in tumors involving the speech areas has an important role to reduce surgical risks. Functional magnetic resonance imaging (fMRI) is the gold standard method to localize cortical speech areas preoperatively, but its availability in clinical routine is difficult. Diffusion MRI based probabilistic tractography is available in head MRI. It’s used to segment cortical subregions by their structural connectivity. In our study, we used probabilistic tractography to localize the frontal and temporal cortical speech areas. 15 patients with left frontal tumor were enrolled to our study. Speech fMRI and diffusion MRI acquired preoperatively. The standard automated anatomical labelling atlas 3 (AAL3) cortical atlas used to define 76 left frontal and 118 left temporal potential speech areas. 4 types of tractography were run according to the structural connection of these regions to the left arcuate fascicle (FA) to localize those cortical areas which have speech functions: 1, frontal through FA; 2, frontal with FA; 3, temporal to FA; 4, temporal with FA connections were determined. Thresholds of 1%, 5%, 10% and 15% applied. At each level, the number of affected frontal and temporal regions by fMRI and tractography were defined, the sensitivity and specificity were calculated. At the level of 1% threshold showed the best results. Sensitivity was 61,631,4% and 67,1523,12%, specificity was 87,210,4% and 75,611,37% for frontal and temporal regions, respectively. From our study, we conclude that probabilistic tractography is a reliable preoperative technique to localize cortical speech areas. However, its results are not feasible that the neurosurgeon rely on during the operation.

Keywords: brain mapping, brain tumor, fMRI, probabilistic tractography

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Authors: Bentayeb-Ait Lounis Saïda, Cheref Zahia, Cherifi Thizi, Ri Kahina Bahmed, Kahina Hallali Yasmine Abdellaoui, Kenza Adli

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Algeria is the leading consumer of dairy products in North Africa. This is a fact. However, the nutritional quality of the latter remains unknown. The aim of this study is to characterise the dairy products available on the Algerian market in order to assess whether they constitute a healthy and safe choice. To do this, it collected data on the labelling of 390 dairy products, including cheese, yoghurt, UHT milk and milk drinks, infant formula and dairy creams. We assessed their degree of processing according to the NOVA classification, as well as the proportion of imitation products. The study was carried out between March 2020 and August 2023. The results show that 88% are ultra-processed; 84% for 'cheese', 92% for dairy creams, 92% for 'yoghurt', 100% for infant formula, 92% for margarines and 36% for UHT milk/dairy drinks. As for imitation/analogue dairy products, the study revealed the following proportions: 100% for infant formula, 78% for butter/margarine, 18% for UHT milk/milk-based drinks, 54% for cheese, 2% for camembert and 75% for dairy cream. The harmful effects of consuming ultra-processed products on long-term health are increasingly documented in dozens of publications. The findings of this study sound the alarm about the health risks to which Algerian consumers are exposed. Various scientific, economic and industrial bodies need to be involved in order to safeguard consumer health in both the short and long term. Food awareness and education campaigns should be organised.

Keywords: dairy, UPF, NOVA, yoghurt, cheese

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Authors: Keivan Davami, Michael Munther, Lloyd Hackel

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The control of properties and material behavior by implementing thermal-mechanical processes is based on mechanical deformation and annealing according to a precise schedule that will produce a unique and stable combination of grain structure, dislocation substructure, texture, and dispersion of precipitated phases. The authors recently developed a thermal-mechanical technique to stabilize the microstructure of additively manufactured nickel-based superalloys even after exposure to high temperatures. However, the mechanism(s) that controls this stability is still under investigation. Laser peening (LP), also called laser shock peening (LSP), is a shock based (50 ns duration) post-processing technique used for extending performance levels and improving service life of critical components by developing deep levels of plastic deformation, thereby generating high density of dislocations and inducing compressive residual stresses in the surface and deep subsurface of components. These compressive residual stresses are usually accompanied with an increase in hardness and enhance the material’s resistance to surface-related failures such as creep, fatigue, contact damage, and stress corrosion cracking. While the LP process enhances the life span and durability of the material, the induced compressive residual stresses relax at high temperatures (>0.5Tm, where Tm is the absolute melting temperature), limiting the applicability of the technology. At temperatures above 0.5Tm, the compressive residual stresses relax, and yield strength begins to drop dramatically. The principal reason is the increasing rate of solid-state diffusion, which affects both the dislocations and the microstructural barriers. Dislocation configurations commonly recover by mechanisms such as climbing and recombining rapidly at high temperatures. Furthermore, precipitates coarsen, and grains grow; virtually all of the available microstructural barriers become ineffective.Our results indicate that by using “cyclic” treatments with sequential LP and annealing steps, the compressive stresses survive, and the microstructure is stable after exposure to temperatures exceeding 0.5Tm for a long period of time. When the laser peening process is combined with annealing, dislocations formed as a result of LPand precipitates formed during annealing have a complex interaction that provides further stability at high temperatures. From a scientific point of view, this research lays the groundwork for studying a variety of physical, materials science, and mechanical engineering concepts. This research could lead to metals operating at higher sustained temperatures enabling improved system efficiencies. The strengthening of metals by a variety of means (alloying, work hardening, and other processes) has been of interest for a wide range of applications. However, the mechanistic understanding of the often complex processes of interactionsbetween dislocations with solute atoms and with precipitates during plastic deformation have largely remained scattered in the literature. In this research, the elucidation of the actual mechanisms involved in the novel cyclic LP/annealing processes as a scientific pursuit is investigated through parallel studies of dislocation theory and the implementation of advanced experimental tools. The results of this research help with the validation of a novel laser processing technique for high temperature applications. This will greatly expand the applications of the laser peening technology originally devised only for temperatures lower than half of the melting temperature.

Keywords: laser shock peening, mechanical properties, indentation, high temperature stability

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Authors: Muhammad Zaman Shakir, Mingfa Yao, Zohaib Iqbal

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This study proposed four Jet fuel surrogate (S1, S2 S3, and 4) with careful selection of seven large hydrocarbon fuel components, ranging from C₉-C₁₆ of higher molecular weight and higher boiling point, adapting the standard molecular distribution size of the actual jet fuel. The surrogate was composed of seven components, including n-propyl cyclohexane (C₉H₁₈), n- propylbenzene (C₉H₁₂), n-undecane (C₁₁H₂₄), n- dodecane (C₁₂H₂₆), n-tetradecane (C₁₄H₃₀), n-hexadecane (C₁₆H₃₄) and iso-cetane (iC₁₆H₃₄). The skeletal jet fuel surrogate reaction mechanism was developed by two approaches, firstly based on a decoupling methodology by describing the C₄ -C₁₆ skeletal mechanism for the oxidation of heavy hydrocarbons and a detailed H₂ /CO/C₁ mechanism for prediction of oxidation of small hydrocarbons. The combined skeletal jet fuel surrogate mechanism was compressed into 128 species, and 355 reactions and thereby can be used in computational fluid dynamics (CFD) simulation. The extensive validation was performed for individual single-component including ignition delay time, species concentrations profile and laminar flame speed based on various fundamental experiments under wide operating conditions, and for their blended mixture, among all the surrogate, S1 has been extensively validated against the experimental data in a shock tube, rapid compression machine, jet-stirred reactor, counterflow flame, and premixed laminar flame over wide ranges of temperature (700-1700 K), pressure (8-50 atm), and equivalence ratio (0.5-2.0) to capture the properties target fuel Jet-A, while the rest of three surrogate S2, S3 and S4 has been validated for Shock Tube ignition delay time only to capture the ignition characteristic of target fuel S-8 & GTL, IPK and RP-3 respectively. Based on the newly proposed HyChem model, another four surrogate with similar components and composition, was developed and parallel validations data was used as followed for previously developed surrogate but at high-temperature condition only. After testing the mechanism prediction performance of surrogates developed by the decoupling methodology, the comparison was done with the results of surrogates developed by the HyChem model. It was observed that all of four proposed surrogates in this study showed good agreement with the experimental measurements and the study comes to this conclusion that like the decoupling methodology HyChem model also has a great potential for the development of oxidation mechanism for heavy alkanes because of applicability, simplicity, and compactness.

Keywords: computational fluid dynamics, decoupling methodology Hychem, jet fuel, surrogate, skeletal mechanism

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Authors: Sinem O. Aktan, Musa Y. Akkurt

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Experimental pressure calibration methods can be classified into three areas: (1) measurements in liquid or gas systems, (2) measurements in static-solid media systems, and (3) measurements in dynamic shock systems. Fluid (liquid and gas) systems high accuracies can be obtainable and commonly used for the calibration method of a pressure sensor. Pressure calibrations can be performed for metrological traceability in two ways, which are on-site (field) and in the laboratory. Laboratory and on-site calibration procedures and the requirements of the DKD-R-6-1 and Euramet cg-17 guidelines will also be addressed. In this study, calibration methods of direct and indirect reading pressure sensor and measurement uncertainty contributions will be explained.

Keywords: pressure metrology, pressure calibration, dead-weight tester, pressure uncertainty

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Authors: B. Sathyanarayana

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As per the report of World Health Organization, more than 80% of world population uses medicines made from herbal and natural materials. They have stood the test of time for their safety, efficacy, cultural acceptability and lesser side effects. Quality assurance and control measures, such as national quality specification and standards for herbal materials, good manufacturing practices (GMP) for herbal medicines, labelling, and licensing schemes for manufacturing, imports and marketing, should be in place in every country where herbal medicines are regulated. These measures are vital for ensuring the safety and efficacy of herbal medicines. In the case of herbal products challenge begins at the stage of designing itself except the classical products. Selection of herbal ingredients, officinal parts to be used, proportions are vital. Once the formulation is designed one should take utmost care to produce the standardized product of assured quality and safety. Quality control measures should cover the validation of quality and identity of raw materials, in process control (as per SOP and GMP norms) and at the level of final product. Quality testing, safety and efficacy studies of the final product are required to ensure the safe and effective use of the herbal products in human beings. Medicinal plants being the materials of natural resource are subjected to great variation making it really difficult to fix quality standards especially in the case of polyherbal preparations. Manufacturing also needs modification according to the type of ingredients present. Hence, it becomes essential to develop Standard operative Procedure for a specific herbal product. Present paper throws a light on the challenges that are encountered during the design and development of herbal products.

Keywords: herbal product, challenges, quality, safety, efficacy

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Authors: Kalinina Anastasiya, Pevnaya Mariya

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The authors present the results of research of educational and cultural habitat of international students at Ural Federal University, revealing problem zones in the organization of adaptation program in 2014-2015 as well as innovations in adaptation program for 2015-2016. The research is based on U-curve theory of culture shock and theory of human capital. The authors provide also the first results for all stakeholders of practically implemented pilot adaptation program for foreign students which was based on the human capital approach.

Keywords: adaptation, human capital, international students, student volunteering, social community, youth politics

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Authors: Jong Won, Park, Sung Hyun, Kim

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The kinetic energy to pass subjected to shock and chisel reciprocating piston hydraulic power supplied by the excavator using for the purpose of crushing the rock, and roads, buildings, etc., hydraulic breakers blow. Impact frequency, efficiency measurement of the impact energy, hydraulic breakers, to demonstrate the ability of hydraulic breaker manufacturers and users to a very important item. And difficult in order to confirm the initial performance degradation in the life of the hydraulic breaker has been thought to be a problem.In this study, we measure the efficiency of hydraulic breaker, Impact energy and Impact frequency, the degradation analysis of research to predict the life.

Keywords: impact energy, impact frequency, hydraulic breaker, life prediction

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Authors: Ming-Hsiang Shih, Wen-Pei Sung, Shih-Heng Tung

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Semi-active control system for structure under excitation of earthquake provides with the characteristics of being adaptable and requiring low energy. DSHD (Displacement Semi-Active Hydraulic Damper) was developed by our research team. Shake table test results of this DSHD installed in full scale test structure demonstrated that this device brought its energy-dissipating performance into full play for test structure under excitation of earthquake. The objective of this research is to develop a new AIC (Active Interaction Control Device) and apply shake table test to perform its dissipation of energy capability. This new proposed AIC is converting an improved DSHD (Displacement Semi-Active Hydraulic Damper) to AIC with the addition of an accumulator. The main concept of this energy-dissipating AIC is to apply the interaction function of affiliated structure (sub-structure) and protected structure (main structure) to transfer the input seismic force into sub-structure to reduce the structural deformation of main structure. This concept is tested using full-scale multi-degree of freedoms test structure, installed with this proposed AIC subjected to external forces of various magnitudes, for examining the shock absorption influence of predictive control, stiffness of sub-structure, synchronous control, non-synchronous control and insufficient control position. The test results confirm: (1) this developed device is capable of diminishing the structural displacement and acceleration response effectively; (2) the shock absorption of low precision of semi-active control method did twice as much seismic proof efficacy as that of passive control method; (3) active control method may not exert a negative influence of amplifying acceleration response of structure; (4) this AIC comes into being time-delay problem. It is the same problem of ordinary active control method. The proposed predictive control method can overcome this defect; (5) condition switch is an important characteristics of control type. The test results show that synchronism control is very easy to control and avoid stirring high frequency response. This laboratory results confirm that the device developed in this research is capable of applying the mutual interaction between the subordinate structure and the main structure to be protected is capable of transforming the quake energy applied to the main structure to the subordinate structure so that the objective of minimizing the deformation of main structural can be achieved.

Keywords: DSHD (Displacement Semi-Active Hydraulic Damper), AIC (Active Interaction Control Device), shake table test, full scale structure test, sub-structure, main-structure

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Authors: F. Nameni, H. Poursadra

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The present study investigated resistance and progressive training alters the expression of chaperone proteins. These proteins function to maintain homeostasis, facilitate repair from injury, and provide protection. Nineteen training female in 2 groups taking part in the intervention volunteered to give blood samples. Levels of chaperone proteins were measured in response to resistance and progressive training. Hsp 70 levels were increased immediately after 2 h progressive training but decreased after resistance training. The data showed that human skeletal muscle responds to the stress of a single period of progressive training by up-regulating and resistance training by down-regulating expression of HSP70. Physical exercise can elevate core temperature and muscle temperatures and the expression pattern of HSP70 due to training status may be attributed to adaptive mechanisms.

Keywords: resistance training, heat shock proteins, leukocytes, Hsp 70

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Authors: Muna Alghabshi, Edmana Krishnan

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A nonlinear Schrodinger equation has been considered for solving by mapping methods in terms of Jacobi elliptic functions (JEFs). The equation under consideration has a linear evolution term, linear and nonlinear dispersion terms, the Kerr law nonlinearity term and three terms representing the contribution of meta materials. This equation which has applications in optical fibers is found to have soliton solutions, shock wave solutions, and singular wave solutions when the modulus of the JEFs approach 1 which is the infinite period limit. The equation with special values of the parameters has also been solved using the tanh method.

Keywords: Jacobi elliptic function, mapping methods, nonlinear Schrodinger Equation, tanh method

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Authors: Goodness C. Aye

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This paper examines the effect of the volatility of oil prices on food price in South Africa using monthly data covering the period 2002:01 to 2014:09. Food price is measured by the South African consumer price index for food while oil price is proxied by the Brent crude oil. The study employs the GARCH-in-mean VAR model, which allows the investigation of the effect of a negative and positive shock in oil price volatility on food price. The model also allows the oil price uncertainty to be measured as the conditional standard deviation of a one-step-ahead forecast error of the change in oil price. The results show that oil price uncertainty has a positive and significant effect on food price in South Africa. The responses of food price to a positive and negative oil price shocks is asymmetric.

Keywords: oil price volatility, food price, bivariate, GARCH-in-mean VAR, asymmetric

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Authors: Poonam Yadav, Dong Bok Lee

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In this study, the Ti-6Al-4V alloy was isothermally and cyclically oxidized at 800oC for 40 hours in air, and its oxidation behavior was characterized in terms of its oxidation rate, scaling rate, and scale spallation tendency. The isothermal oxidation tests indicated that Ti-6Al-4V oxidized fast and almost linearly, forming thick oxide scales. However, the scales that formed during isothermal oxidation were adherent. The cyclic oxidation tests indicated that the scales that formed on Ti-6Al-4V were highly susceptible to spallation owing to the large growth stress arisen and the thermal stress imposed during thermal cyclings. The formed scales frequently delaminated into several pieces owing to the excessive stress aroused by the repetitive thermal shock. Particularly, excessive oxidation and heavy spallation occurred at the edge of Ti-6Al-4V during cyclic oxidation.

Keywords: cyclic, isothermal, oxidation, spallation

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Authors: A. I. Dovgjallo, A. B. Tsapkova, A. A. Shimanov

Abstract:

The paper is devoted to one of engine types with external heating – a thermoacoustic engine. In thermoacoustic engine heat energy is converted to an acoustic energy. Further, acoustic energy of oscillating gas flow must be converted to mechanical energy and this energy in turn must be converted to electric energy. The most widely used way of transforming acoustic energy to electric one is application of linear generator or usual generator with crank mechanism. In both cases, the piston is used. Main disadvantages of piston use are friction losses, lubrication problems and working fluid pollution which cause decrease of engine power and ecological efficiency. Using of a bidirectional impulse turbine as an energy converter is suggested. The distinctive feature of this kind of turbine is that the shock wave of oscillating gas flow passing through the turbine is reflected and passes through the turbine again in the opposite direction. The direction of turbine rotation does not change in the process. Different types of bidirectional impulse turbines for thermoacoustic engines are analyzed. The Wells turbine is the simplest and least efficient of them. A radial impulse turbine has more complicated design and is more efficient than the Wells turbine. The most appropriate type of impulse turbine was chosen. This type is an axial impulse turbine, which has a simpler design than that of a radial turbine and similar efficiency. The peculiarities of the method of an impulse turbine calculating are discussed. They include changes in gas pressure and velocity as functions of time during the generation of gas oscillating flow shock waves in a thermoacoustic system. In thermoacoustic system pressure constantly changes by a certain law due to acoustic waves generation. Peak values of pressure are amplitude which determines acoustic power. Gas, flowing in thermoacoustic system, periodically changes its direction and its mean velocity is equal to zero but its peak values can be used for bi-directional turbine rotation. In contrast with feed turbine, described turbine operates on un-steady oscillating flows with direction changes which significantly influence the algorithm of its calculation. Calculated power output is 150 W with frequency 12000 r/min and pressure amplitude 1,7 kPa. Then, 3-d modeling and numerical research of impulse turbine was carried out. As a result of numerical modeling, main parameters of the working fluid in turbine were received. On the base of theoretical and numerical data model of impulse turbine was made on 3D printer. Experimental unit was designed for numerical modeling results verification. Acoustic speaker was used as acoustic wave generator. Analysis if the acquired data shows that use of the bi-directional impulse turbine is advisable. By its characteristics as a converter, it is comparable with linear electric generators. But its lifetime cycle will be higher and engine itself will be smaller due to turbine rotation motion.

Keywords: acoustic power, bi-directional pulse turbine, linear alternator, thermoacoustic generator

Procedia PDF Downloads 378

Authors: Maciej Szelag

Abstract:

The discovery of the carbon nanotubes (CNT), has led to a breakthrough in the material engineering. The CNT is characterized by very large surface area, very high Young's modulus (about 2 TPa), unmatched durability, high tensile strength (about 50 GPa) and bending strength. Their diameter usually oscillates in the range from 1 to 100 nm, and the length from 10 nm to 10-2 m. The relatively new approach is the CNT’s application in the concrete technology. The biggest problem in the use of the CNT to cement composites is their uneven dispersion and low adhesion to the cement paste. Putting the nanotubes alone into the cement matrix does not produce any effect because they tend to agglomerate, due to their large surface area. Most often, the CNT is used as an aqueous suspension in the presence of a surfactant that has previously been sonicated. The paper presents the results of investigations of the basic physical properties (apparent density, shrinkage) and mechanical properties (compression and tensile strength) of cement paste with the addition of the multiwall carbon nanotubes (MWCNT). The studies were carried out on four series of specimens (made of two different Portland Cement). Within each series, samples were made with three w/c ratios – 0.4, 0.5, 0.6 (water/cement). Two series were an unmodified cement matrix. In the remaining two series, the MWCNT was added in amount of 0.1% by cement’s weight. The MWCNT was used as an aqueous dispersion in the presence of a surfactant – SDS – sodium dodecyl sulfate (C₁₂H₂₅OSO₂ONa). So prepared aqueous solution was sonicated for 30 minutes. Then the MWCNT aqueous dispersion and cement were mixed using a mechanical stirrer. The parameters were tested after 28 days of maturation. Additionally, the change of these parameters was determined after samples temperature loading at 250°C for 4 hours (thermal shock). Measurement of the apparent density indicated that cement paste with the MWCNT addition was about 30% lighter than conventional cement matrix. This is due to the fact that the use of the MWCNT water dispersion in the presence of surfactant in the form of SDS resulted in the formation of air pores, which were trapped in the volume of the material. SDS as an anionic surfactant exhibits characteristics specific to blowing agents – gaseous and foaming substances. Because of the increased porosity of the cement paste with the MWCNT, they have obtained lower compressive and tensile strengths compared to the cement paste without additive. It has been observed, however, that the smallest decreases in the compressive and tensile strength after exposure to the elevated temperature achieved samples with the MWCNT. The MWCNT (well dispersed in the cement matrix) can form bridges between hydrates in a nanoscale of the material’s structure. Thus, this may result in an increase in the coherent cohesion of the cement material subjected to a thermal shock. The obtained material could be used for the production of an aerated concrete or using lightweight aggregates for the production of a lightweight concrete.

Keywords: cement paste, elevated temperature, mechanical parameters, multiwall carbon nanotubes, physical parameters, SDS

Procedia PDF Downloads 354

Authors: Stefan Gruden, Charlott Brunmark, Bo Holmqvist, Erwin D. Brenndorfer, Martin Johansson, Jian Liu, Ying Zhao, Niklas Axen, Moustapha Hassan

Abstract:

Aim: The study was designed to evaluate the ability of the calcium sulfate-based NanoZolid® drug delivery technology to locally release the epidermal growth factor (EGF) protein while maintaining its biological activity. Methods: NanoZolid-formulated EGF protein labelled with a near-infrared dye (EGF-NIR) depots or EGF-NIR dissolved in PBS were injected subcutaneously into mice bearing EGF receptor (EGFR) positive human A549 lung cancer tumors inoculated subcutaneously. The release and biodistribution of the EGF-NIR were investigated in vivo longitudinally up to 96 hours post-administration, utilizing whole-body fluorescence imaging. In order to confirm the in vivo findings, histological analysis of tumor cryosections was performed to investigate EGF-NIR fluorescent signal and EGFR expression level by immunofluorescence labelling. Results: The in vivo fluorescence imaging showed a controlled release profile of the EGF-NIR loaded in the NanoZolid depots compared to free EGF-NIR. Histological analysis of the tumors further demonstrated a prevailing distribution of EGF-NIR in regions with high levels of EGFR expression. Conclusion: Calcium sulfate based depots can be used to formulate EGF while maintaining its biological activity, e.g., receptor binding capability. This may have good clinical potential for local delivery of biomolecules to enhance treatment efficacy and minimize systemic adverse effects.

Keywords: bioresorbable, calcium sulfate, controlled release, NanoZolid

Procedia PDF Downloads 165

Authors: I. Mnafeg, A. Abichou, L. Beji

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Traditional mechanical control systems in thrust vectoring are efficient in rocket thrust guidance but their costs and their weights are excessive. The fluidic injection in the nozzle divergent constitutes an alternative procedure to achieve the goal. In this paper, we present a 3D analytical model for fluidic injection in a supersonic nozzle integrating an orifice. The fluidic vectoring uses a sonic secondary injection in the divergent. As a result, the flow and interaction between the main and secondary jet has built in order to express the pressure fields from which the forces and thrust vectoring are deduced. Under various separation criteria, the present analytical model results are compared with the existing numerical and experimental data from the literature.

Keywords: flow separation, fluidic thrust vectoring, nozzle, secondary jet, shock wave

Procedia PDF Downloads 296

Authors: Raymond K. Dziwornu

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Lending rate of agriculture loan has persistently been high and attributed to risk in the sector. This study examined how food inflation and agriculture lending rate react to each other in Ghana using vector autoregressive approach. Quarterly data from 2006 to 2018 was obtained from the Bank of Ghana quarterly bulletin and the Ghana Statistical Service reports. The study found that a positive standard deviation shock to food inflation causes lending rate of agriculture loan to react negatively in the short run, but positively and steadily in the long run. This suggests the need to direct appropriate policy measures to reduce food inflation and consequently, the cost of credit to the agricultural sector for its growth.

Keywords: food inflation, agriculture, lending rate, vector autoregressive, Ghana

Procedia PDF Downloads 149

Authors: Professor Jo Angouri, Polina Mesinioti, Chris Turner

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In order for a group of ad-hoc professional to perform as a team, a shared understanding of the problem at hand and an agreed action plan are necessary components. This is particularly significant in complex, time sensitive professional settings such as in trauma emergencies. In this context, team briefings prior to the patient arrival (pre-briefings) constitute a critical event for the performance of the team; they provide the necessary space for co-constructing a shared understanding of the situation through summarising information available to the team: yet the act of summarising is widely assumed in medical practice but not systematically researched. In the vast teamwork literature, terms such as ‘shared mental model’, ‘mental space’ and ‘cognate labelling’ are used extensively, and loosely, to denote the outcome of the summarising process, but how exactly this is done interactionally remains under researched. This paper reports on the forms and functions of pre-briefings in a major trauma centre in the UK. Taking an interactional approach, we draw on 30 simulated and real-life trauma emergencies (15 from each dataset) and zoom in on the use of pre-briefings, which we consider focal points in the management of trauma emergencies. We show how ad hoc teams negotiate sharedness of future orientation through summarising, synthesising information, and establishing common understanding of the situation. We illustrate the role, characteristics, and structure of pre-briefing sequences that have been evaluated as ‘efficient’ in our data and the impact (in)effective pre-briefings have on teamwork. Our work shows that the key roles in the event own the act of summarising and we problematise the implications for leadership in trauma emergencies. We close the paper with a model for pre-briefing and provide recommendations for clinical practice, arguing that effective pre-briefing practice is teachable.

Keywords: summarising, medical emergencies, interaction analysis, shared/mental models

Procedia PDF Downloads 93

Authors: Visith Siriphuwanun, Yodying Punjasawadwong, Suwinai Saengyo, Kittipan Rerkasem

Abstract:

Objective: To determine incidences and factors associated with perioperative cardiac arrest in trauma patients who received anesthesia for emergency surgery. Design and setting: Retrospective cohort study in trauma patients during anesthesia for emergency surgery at a university hospital in northern Thailand country. Patients and methods: This study was permitted by the medical ethical committee, Faculty of Medicine at Maharaj Nakorn Chiang Mai Hospital, Thailand. We clarified data of 19,683 trauma patients receiving anesthesia within a decade between January 2007 to March 2016. The data analyzed patient characteristics, traumas surgery procedures, anesthesia information such as ASA physical status classification, anesthesia techniques, anesthetic drugs, location of anesthesia performed, and cardiac arrest outcomes. This study excluded the data of trauma patients who had received local anesthesia by surgeons or monitoring anesthesia care (MAC) and the patient which missing more information. The factor associated with perioperative cardiac arrest was identified with univariate analyses. Multiple regressions model for risk ratio (RR) and 95% confidence intervals (CI) were used to conduct factors correlated with perioperative cardiac arrest. The multicollinearity of all variables was examined by bivariate correlation matrix. A stepwise algorithm was chosen at a p-value less than 0.02 was selected to further multivariate analysis. A P-value of less than 0.05 was concluded as statistically significant. Measurements and results: The occurrence of perioperative cardiac arrest in trauma patients receiving anesthesia for emergency surgery was 170.04 per 10,000 cases. Factors associated with perioperative cardiac arrest in trauma patients were age being more than 65 years (RR=1.41, CI=1.02–1.96, p=0.039), ASA physical status 3 or higher (RR=4.19–21.58, p < 0.001), sites of surgery (intracranial, intrathoracic, upper intra-abdominal, and major vascular, each p < 0.001), cardiopulmonary comorbidities (RR=1.55, CI=1.10–2.17, p < 0.012), hemodynamic instability with shock prior to receiving anesthesia (RR=1.60, CI=1.21–2.11, p < 0.001) , special techniques for surgery such as cardiopulmonary bypass (CPB) and hypotensive techniques (RR=5.55, CI=2.01–15.36, p=0.001; RR=6.24, CI=2.21–17.58, p=0.001, respectively), and patients who had a history of being alcoholic (RR=5.27, CI=4.09–6.79, p < 0.001). Conclusion: Incidence of perioperative cardiac arrest in trauma patients receiving anesthesia for emergency surgery was very high and correlated with many factors, especially age of patient and cardiopulmonary comorbidities, patient having a history of alcoholic addiction, increasing ASA physical status, preoperative shock, special techniques for surgery, and sites of surgery including brain, thorax, abdomen, and major vascular region. Anesthesiologists and multidisciplinary teams in pre- and perioperative periods should remain alert for warning signs of pre-cardiac arrest and be quick to manage the high-risk group of surgical trauma patients. Furthermore, a healthcare policy should be promoted for protecting against accidents in high-risk groups of the population as well.

Keywords: perioperative cardiac arrest, trauma patients, emergency surgery, anesthesia, factors risk, incidence

Procedia PDF Downloads 169

Authors: Carolina Aparicio-Fernández, Alejandro Vilar Abad, Mar Cañada Soriano, Jose-Luis Vivancos

Abstract:

The building sector is responsible for 40% of the total energy consumption in the European Union (EU). Thus, implementation of strategies for quantifying and reducing buildings energy consumption is indispensable for reaching the EU’s carbon neutrality and energy efficiency goals. Each Member State has transposed the European Directives according to its own peculiarities: existing technical legislation, constructive solutions, climatic zones, etc. Therefore, in accordance with the Energy Performance of Buildings Directive, Member States have developed different Energy Performance Certificate schemes, using proposed energy simulation software-tool for each national or regional area. Energy Performance Certificates provide a powerful and comprehensive information to predict, analyze and improve the energy demand of new and existing buildings. Energy simulation software and databases allow a better understanding of the current constructive reality of the European building stock. However, Energy Performance Certificates still have to face several issues to consider them as a reliable and global source of information since different calculation tools are used that do not allow the connection between them. In this document, TRNSYS (TRaNsient System Simulation program) software is used to calculate the energy demand of a building, and it is compared with the energy labeling obtained with Spanish Official software-tools. We demonstrate the possibility of using not official software-tools to calculate the Energy Performance Certificate. Thus, this approach could be used throughout the EU and compare the results in all possible cases proposed by the EU Member States. To implement the simulations, an isolated single-family house with different construction solutions is considered. The results are obtained for every climatic zone of the Spanish Technical Building Code.

Keywords: energy demand, energy performance certificate EPBD, trnsys, buildings

Procedia PDF Downloads 126

Authors: Bienvenu Gael Fouda Mbanga

Abstract:

This study reports a new approach of preparation of carbon nanoparticles coated cerium oxide nanorods (CNPs/CeONRs) nanocomposite and reusing the spent adsorbent of Cd2+- CNPs/CeONRs nanocomposite for latent fingerprint detection (LFP) after removing Cd2+ ions from aqueous solution. CNPs/CeONRs nanocomposite was prepared by using CNPs and CeONRs with adsorption processes. The prepared nanocomposite was then characterized by using UV-visible spectroscopy (UV-visible), Fourier transforms infrared spectroscopy (FTIR), X-ray diffraction pattern (XRD), scanning electron microscope (SEM), Transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), Zeta potential, X-ray photoelectron spectroscopy (XPS). The average size of the CNPs was 7.84nm. The synthesized CNPs/CeONRs nanocomposite has proven to be a good adsorbent for Cd2+ removal from water with optimum pH 8, dosage 0. 5 g / L. The results were best described by the Langmuir model, which indicated a linear fit (R2 = 0.8539-0.9969). The adsorption capacity of CNPs/CeONRs nanocomposite showed the best removal of Cd2+ ions with qm = (32.28-59.92 mg/g), when compared to previous reports. This adsorption followed pseudo-second order kinetics and intra particle diffusion processes. ∆G and ∆H values indicated spontaneity at high temperature (40oC) and the endothermic nature of the adsorption process. CNPs/CeONRs nanocomposite therefore showed potential as an effective adsorbent. Furthermore, the metal loaded on the adsorbent Cd2+- CNPs/CeONRs has proven to be sensitive and selective for LFP detection on various porous substrates. Hence Cd2+-CNPs/CeONRs nanocomposite can be reused as a good fingerprint labelling agent in LFP detection so as to avoid secondary environmental pollution by disposal of the spent adsorbent.

Keywords: Cd2+-CNPs/CeONRs nanocomposite, cadmium adsorption, isotherm, kinetics, thermodynamics, reusable for latent fingerprint detection

Procedia PDF Downloads 121