Search results for: HVOF (High Velocity Oxygen Fuel)

Authors: Bator Shagdyrov, Elena Zorina, Tamara Nesterenko

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The aim of the research was to develop a design of micromechanical gyroscope, which will be used in the automotive industry, safety systems and anti-lock braking system. The research resulted in improvement of one of the technical parameters – bandwidth. In the process of mass production of micromechanical sensors, problems occurred with their use. One of the problems was a narrow bandwidth typical for the gyroscopes with a high-quality factor. A constructive way of increasing bandwidth is to use multimass systems via secondary oscillations axis. When constructing, the main task was to choose the frequency - phases and antiphases as close to each other as possible, and set the frequency of the primary oscillation evenly between them. Investigations are carried out using the T-Flex CAD finite element program and T-Flex ANALYSIS support package. The results obtained are planned to use in the future for the production of an experimental model of development and testing in practice of characteristics derived by theoretical means.

Keywords: bandwidth, inertial mass, mathematical model, micromechanical gyroscope, micromechanics

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Authors: Guilherme M. Pereira, Kimmo Teinïla, Danilo Custódio, Risto Hillamo, Célia Alves, Pérola de C. Vasconcellos

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South American large cities often present serious air pollution problems and their atmosphere composition is influenced by a variety of emissions sources. The South American Emissions Megacities, and Climate project (SAEMC) has focused on the study of emissions and its influence on climate in the South American largest cities and it also included Lima (Peru) and Medellin (Colombia), sites where few studies of the genre were done. Lima is a coastal city with more than 8 million inhabitants and the second largest city in South America. Medellin is a 2.5 million inhabitants city and second largest city in Colombia; it is situated in a valley. The samples were collected in quartz fiber filters in high volume samplers (Hi-Vol), in 24 hours of sampling. The samples were collected in intensive campaigns in both sites, in July, 2010. Several species were determined in the aerosol samples of Lima and Medellin. Organic and elemental carbon (OC and EC) in thermal-optical analysis; biomass burning tracers (levoglucosan - Lev, mannosan - Man and galactosan - Gal) in high-performance anion exchange ion chromatography with mass spectrometer detection; water soluble ions in ion chromatography. The average particulate matter was similar for both campaigns, the PM10 concentrations were above the recommended by World Health Organization (50 µg m⁻³ – daily limit) in 40% of the samples in Medellin, while in Lima it was above that value in 15% of the samples. The average total ions concentration was higher in Lima (17450 ng m⁻³ in Lima and 3816 ng m⁻³ in Medellin) and the average concentrations of sodium and chloride were higher in this site, these species also had better correlations (Pearson’s coefficient = 0,63); suggesting a higher influence of marine aerosol in the site due its location in the coast. Sulphate concentrations were also much higher at Lima site; which may be explained by a higher influence of marine originated sulphate. However, the OC, EC and monosaccharides average concentrations were higher at Medellin site; this may be due to the lower dispersion of pollutants due to the site’s location and a larger influence of biomass burning sources. The levoglucosan average concentration was 95 ng m⁻³ for Medellin and 16 ng m⁻³ and OC was well correlated with levoglucosan (Pearson’s coefficient = 0,86) in Medellin; suggesting a higher influence of biomass burning over the organic aerosol in this site. The Lev/Man ratio is often related to the type of biomass burned and was close to 18, similar to the observed in previous studies done at biomass burning impacted sites in the Amazon region; backward trajectories also suggested the transport of aerosol from that region. Biomass burning appears to have a larger influence on the air quality in Medellin, in addition the vehicular emissions; while Lima showed a larger influence of marine aerosol during the study period.

Keywords: aerosol transport, atmospheric particulate matter, biomass burning, SAEMC project

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Authors: Jumazulhisham Abdul Shukor, Mohd. Sazali Said, Roshanizah Harun, Shuib Husin, Ahmad Razlee Ab Kadir

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This paper applies Taguchi Optimization Method in determining the best machining parameters for pocket milling process on Polypropylene (PP) using CNC milling machine where the surface roughness is considered and the Carbide inserts cutting tool are used. Three machining parameters; speed, feed rate and depth of cut are investigated along three levels; low, medium and high of each parameter (Taguchi Orthogonal Arrays). The setting of machining parameters were determined by using Taguchi Method and the Signal-to-Noise (S/N) ratio are assessed to define the optimal levels and to predict the effect of surface roughness with assigned parameters based on L9. The final experimental outcomes are presented to prove the optimization parameters recommended by manufacturer are accurate.

Keywords: inserts, milling process, signal-to-noise (S/N) ratio, surface roughness, Taguchi Optimization Method

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Authors: Christer Frennfelt

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Solar heating is the most environmentally friendly way to heat water. Brazed Plate Heat Exchangers (BPHEs) are a key component in many solar heating applications for harvesting solar energy into accumulator tanks, producing hot tap water, and heating pools. The combination of high capacity in a compact format, efficient heat transfer, and fast response makes the BPHE the ideal heat exchanger for solar thermal systems. Solar heating is common as a standalone heat source, and as an add-on heat source for boilers, heat pumps, or district heating systems. An accumulator provides the possibility to store heat, which enables combination of different heat sources to a larger extent. In turn this works as protection to reduced access to energy or increased energy prices. For example heat from solar panels is preferably stored during the day for use at night.

Keywords: district heating and cooling, thermal storage, brazed plate heat exchanger, solar domestic hot water and combisystems

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Authors: Devin Atkin, Orly Yadid-Pecht

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The continual demands for increasing resolution and dynamic range in CMOS image sensors have resulted in exponential increases in the amount of data that needs to be read out of an image sensor, and existing readouts cannot keep up with this demand. Interesting approaches such as sparse and burst readouts have been proposed and show promise, but at considerable trade-offs in other specifications. To this end, we have begun designing and evaluating various new readout topologies centered around an attempt to parallelize the sensor readout. In this paper, we have designed, simulated, and started testing a new light-controlled oscillator topology with dual column and row readouts. We expect the parallel readout structure to offer greater speed and alleviate the trade-off typical in this topology, where slow pixels present a major framerate bottleneck.

Keywords: CMOS image sensors, high-speed capture, wide dynamic range, light controlled oscillator

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Authors: Naoual Boussoualim, Hayat Trabsa, Iman Krache, Lekhmici Arrar, Abderrahmane Baghiani

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Resistance to antibiotics has emerged following their widespread use; the important mechanism of beta-lactam resistance in bacteria is the production of beta-lactamase. In order to find new bioactive beta-lactamase inhibitors, this study investigated the inhibition effect of the extracts of Anchusa azurea (AA) on a beta-lactamase from Bacillus cereus. The extracts exerted inhibitory effects on beta-lactamase in a dose-dependent manner, the results showed that the crude extract (BrE) and the ethyl acetate extract (AcE) of Anchusa azurea showed a very high inhibitory activity at a concentration of 10 mg, the percentage of inhibition was between 58% and 68%. Not all extracts were as potent as the original inhibitors such as clavulanic acid, the isolation and the structural elucidation of the active constituents in these extracts will provide useful means in the development of beta -lactamase inhibitors.

Keywords: Anchusa azurea, natural product, resistance, antibiotics, beta-lactamase, inhibitors

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Authors: Nasreen Abdulmannan

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Fetal abnormalities are categorized as a structural abnormality, non-structural abnormality, or a combination of both. Fetal structural abnormalities (FSA) include, but are not limited, to Down syndrome, congenital diaphragmatic hernia, and cleft lip and palate. These abnormalities can be detected in the first weeks of pregnancy, which is almost around 9 - 20 weeks gestational. Etiological factors for FSA are unknown; however, transmitted genetic risk can be one of these factors. Consanguineous marriage often referred to as inbreeding, represents a significant risk factor for FSA due to the increased likelihood of deleterious genetic traits shared by both biological parents. In a country such as the Kingdom of Saudi Arabia (KSA), consanguineous marriage is high, which creates a significant risk of children being born with congenital abnormalities. Historically, the practice of consanguinity occurred commonly among European royalty. For example, Great Britain’s Queen Victoria married her German first cousin, Prince Albert of Coburg. Although a distant blood relationship, the United Kingdom’s Queen Elizabeth II married her cousin, Prince Philip of Greece and Denmark—both of them direct descendants of Queen Victoria. In Middle Eastern countries, a high incidence of consanguineous unions still exists, including in the KSA. Previous studies indicated that a significant gap exists in understanding the lived experiences of Saudi women dealing with an FSA-complicated pregnancy. Eleven participants were interviewed using a semi-structured interview format for this qualitative phenomenological study investigating the lived experiences of pregnant Saudi women carrying a child with FSA. This study explored the gaps in current literature regarding the lived experiences of pregnant Saudi women whose pregnancies were complicated by FSA. In addition, the researcher acquired knowledge about the available support and resources as well as the Saudi cultural perspective on FSA. This research explored the lived experiences of pregnant Saudi women utilizing Giorgi’s (2009) approach to data collection and data management. Findings for this study cover five major themes: (1) initial maternal reaction to the FSA diagnosis per ultrasound screening; (2) strengthening of the maternal relationship with God; (3) maternal concern for their child’s future; (4) feeling supported by their loved ones; and (5) lack of healthcare provider support and guidance. Future research in the KSA is needed to explore the network support for these mothers. This study recommended further clinical nursing research, nursing education, clinical practice, and healthcare policy/procedures to provide opportunities for improvement in nursing care and increase awareness in KSA society.

Keywords: fetal structural abnormalities, psychological distress, health provider, health care

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Authors: Mehrnaz Alibeikloo, Hajar Share Isfahani, Hadi Khabbaz

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In recent years, by developing cities and increasing population, reconstructing on closed landfill sites in some regions is unavoidable. Long-term settlement is one of the major concerns associated with reconstruction on landfills after closure. The purpose of this research is evaluating the effect of preloading in various patterns of height and time on long-term settlements of closed landfills. In this regard, five scenarios of surcharge from 1 to 3 m high within 3, 4.5 and 6 months of preloading time have been modeled using PLAXIS 2D software. Moreover, the numerical results have been compared to those obtained from analytical methods, and a good agreement has been achieved. The findings indicate that there is a linear relationship between settlement and surcharge height. Although, long-term settlement decreased by applying a longer and higher preloading, the time of preloading was found to be a more effective factor compared to preloading height.

Keywords: preloading, long-term settlement, landfill, PLAXIS 2D

Procedia PDF Downloads 195

Authors: M. Esmailian, M. Shakouri, A. Mottahedi, S. G. Shabestari

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Heat treatable aluminium alloys such as 7075 and 7055, because of high strength and low density, are used widely in aircraft industry. For best mechanical properties, T6 heat treatment has recommended for this regards, but this temper treatment is sensitive to corrosion induced and Stress Corrosion Cracking (SCC) damage. For improving this property, the over-aging treatment (T7) applies to this alloy, but it decreases the mechanical properties up to 30 percent. Hence, to increase the mechanical properties, without any remarkable decrease in SCC resistant, Retrogression and Re-Aging (RRA) heat treatment is used. This treatment performs in a relatively short time. In this paper, the RRA heat treatment was applied to 7055 aluminum alloy and then effect of RRA time on the mechanical properties of 7055 has been investigated. The results show that the 40 minute time is suitable time for retrogression of 7055 aluminum alloy and ultimate strength increases up to 625MPa.

Keywords: 7055 Aluminum alloy, mechanical properties, SCC resistance, heat Treatment

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Authors: Hailang Yang

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To ensure the confidentiality and integrity of speech signals in communication transmission, this paper proposes a voice signal encryption scheme based on chaotic theory. Firstly, the scheme utilizes chaotic mapping to generate a key stream and then employs the key stream to perform bitwise exclusive OR (XOR) operations for encrypting the speech signal. Additionally, the scheme utilizes a chaotic hash function to generate a Message Authentication Code (MAC), which is appended to the encrypted data to verify the integrity of the data. Subsequently, we analyze the security performance and encryption efficiency of the scheme, comparing and optimizing it against existing solutions. Finally, experimental results demonstrate that the proposed scheme can resist common attacks, achieving high-quality encryption and speed.

Keywords: chaotic theory, XOR encryption, chaotic hash function, Message Authentication Code (MAC)

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Authors: Michael S. Goodman

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The Joint Intelligence Committee (JIC) has been the senior most analytical body in the UK since its creation in 1936. At various points in its history, most notably and recently in 2004, in the wake of the Iraq war, questions have been asked about its analytical process. In 1968 the British intelligence community saw one of its biggest transformations: the creation of an independent, central cadre of analysts. The ‘Assessments Staff’ was a novel attempt to improve the quality of analysis by fostering independence from departmental biases that had long plagued British intelligence. Seconded into the Cabinet Office, staff were allocated a ‘desk,’ and their role was to produce high level assessments for the most senior readers in the land. At the same time, efforts were made to ‘professionalise’ the analysts. This paper is based on a detailed archival examination of the JIC’s documentary files. It will recount the reasons behind this organisational reform, what the changes entailed, and whether they were a success. The changes were immediately brought to bear with the intelligence assessments prior to the Soviet invasion of Czechoslovakia, something that the JIC failed to appreciate.

Keywords: intelligence, cold war history, analysis, united kingdom

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Authors: Mauricio George Miguel Jardini, Jose Antonio Jardini

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Transmission power utilities participate with kilometers of circuits, many with particularities in terms of vegetation growth. To control these rights-of-way, maintenance teams perform ground, and air inspections, and the identification method is subjective (indirect). On a ground inspection, when identifying an irregularity, for example, high vegetation threatening contact with the conductor cable, pruning or suppression is performed immediately. In an aerial inspection, the suppression team is mobilized to the identified point. This work investigates the use of 3D modeling of a transmission line segment using RGB (red, blue, and green) images and LiDAR (Light Detection and Ranging) sensor data. Both sensors are coupled to unmanned aerial vehicle. The goal is the accurate and timely detection of vegetation along the right-of-way that can cause shutdowns.

Keywords: 3D modeling, LiDAR, right-of-way, transmission lines, vegetation

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Authors: Fahad Alamoudi, Yaser Miaji, Fawzy Jalalah

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The growing popularity of swimming pools and other activities in the water for sport, fitness, therapy or just enjoyable relaxation have led to the increased use of swimming pools and the establishment of a variety of specific-use pools such as spa pools, Waterslides and more recently, hydrotherapy and wave pools. In this research a few simple equipments are used for test, Detect and alert for detection of water cleanness and pollution. YSI Photometer Systems, TDSTestr High model, rio 12HF, and Electrode A1. The researchers used electrolysis as a method of separating bonded elements and compounds by passing an electric current through them. The results which use 41 experiments show the higher the salt concentration, the more efficient the electrode and the smaller the gap between the plates and The lower the electrode voltage. Furthermore, it is proved that the larger the surface area, the lower the cell voltage and the higher current used the more chlorine produced.

Keywords: photometer, electrode, electrolysis, swimming pool chlorination

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Authors: Mikhail S. Zastrozhin, Valery V. Smirnov, Dmitry A. Sychev, Ludmila M. Savchenko, Evgeny A. Bryun, Mark O. Nechaev

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Cytochrome P-450 isoenzyme 3A4 takes part in the biotransformation of medical drugs. The activity of CYP isoenzymes depends on genetic (polymorphisms of genes which encoded it) and phenotypic factors (a kind of food, a concomitant drug therapy). The aim of the study was to evaluate a carbamazepine effect on the CYP3A4 activity in patients with alcohol addiction. The study included 25 men with alcohol dependence, who received haloperidol during the exacerbation of the addiction. CYP3A4 activity was assessed by urinary 6-beta-hydroxycortisol/cortisol ratios measured by high performance liquid chromatography with mass spectrometry. The study modeled a graph and an equation of the logarithmic regression, that reflects the dependence of CYP3A4 activity on a dose of carbamazepine: y = 5,5 * 9,1 * 10-5 * x2. The study statistically significant demonstrates the effect of carbamazepine on CYP2D6 isozyme activity in patients with alcohol addiction.

Keywords: CYP3A4, biotransformation, carbamazepine, alcohol abuse

Procedia PDF Downloads 279

Authors: Nadia Degregori

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This paper focuses on Peru’s Environmental Impact Assessment’s communication and participation mechanisms, whose rationale is to prevent conflictive situations by –supposedly- providing high-quality information about mining projects and their impacts to affected stakeholders. It is argued that, in fact, these mechanisms enhance citizens’ feelings of fear and/or mistrust towards mining projects and the companies behind them because their design follows a top-down perspective that limits “participation” to a passive reception of information, and which does not address power unbalances between communities and companies or government. As well, the paper contends that this way of managing the social aspects of Environmental Impact Assessments in Peru leads stakeholders who possess less power (typically communities) to incline towards maintaining the status quo and avoiding negotiations with either the central government or mining companies as a defence mechanism for avoiding a bad negotiation.

Keywords: community relations, environmental impact assessments, governance and participation, mining, Peru

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Authors: Rachid Dehini, Brahim Berbaoui

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The main objectives of shunt active power filter (SAPF) is to preserve the power system from unwanted harmonic currents produced by nonlinear loads, as well as to compensate the reactive power. The aim of this paper is to present a (PAPF) supplied by the Photovoltaic cells ,in such a way that the (PAPF) feeds the linear and nonlinear loads by harmonics currents and the excess of the energy is injected into the power system. In order to improve the performances of conventional (PAPF) This paper also proposes artificial neural networks (ANN) for harmonics identification and DC link voltage control. The simulation study results of the new (SAPF) identification technique are found quite satisfactory by assuring good filtering characteristics and high system stability.

Keywords: SAPF, harmonics current, photovoltaic cells, MPPT, artificial neural networks (ANN)

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Authors: Areeg Shermaddo

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Solar updraft power plants (SUPP) provide a great potential for green and environmentally friendly renewable power generation. An up to 1000 m high chimney represents one of the major parts of each SUPP, which consist of the main shell structure and the stiffening rings. Including the nonlinear material behavior in a simulation of the chimney is computationally a demanding task. However, allowing the formation of cracking in concrete leads to a more economical design of the structure. In this work, an FE model of a SUPP is presented incorporating the nonlinear material behavior. The effect of wind loading intensity on the structural response is explored. Furthermore, the influence of the stiffness of the ring beams on the global behavior is as well investigated. The obtained results indicate that the minimum reinforcement is capable of carrying the tensile stresses provided that the ring beams are rather stiff.

Keywords: ABAQUS, nonlinear analysis, ring beams, SUPP

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Authors: Jenny Kwon

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Following the outbreak of the COVID-19 pandemic globally, another type of pandemic, ageism, appeared on the surface. Ageism, the stereotypes, prejudice, and discrimination directed towards others or oneself based on chronological age, has adversely impacted older adults' lives during the pandemic. In the short term, older adults struggled with health issues (e.g., high rate of infection and mortality) and experienced social disconnection (e.g., loneliness and depression). Ultimately, older adults' self-perceptions of aging, self-esteem and intergenerational relationships were negatively influenced. To closely look into the impact of ageism during the pandemic on U.S. older adults' aging process, the current study has three specific purposes. First, the study introduces a theoretical foundation (i.e., stereotype embodiment theory) in the development of ageism research. Second, the study reports on examples of ageism toward U.S. older adults manifested in the context of COVID-19. Finally, collective responsibilities and future research directions are proposed to fight against ageism.

Keywords: ageism, COVID-19, older adults, pandemic, stereotype embodiment

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Authors: Halima Kilungu, Munishi P. K. T., Happiness Jackson Nko

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Wetlands contribute significantly to the national economy. Nevertheless, urban wetlands in Tanzania have been taken for granted; many have been converted into waste disposal areas and settlements despite their substantial role in climate-change flood attenuation and livelihood. This is due to the lacking informing assessments from a socio-economic perspective. This study assesses the contribution of urban wetlands to the livelihood of marginalised communities in Dar es Salaam City, Tanzania. Specifically, the study assesses the an extent and nature of change in wetlands in Dar es Salaam City for the past 30 years using the land-use land-cover change approach and the contribution of wetlands to livelihood using questionnaires. The results show that the loss of wetlands in Dar es Salaam is high to extent that will likely jeopardise their future contributions to livelihood. The results inform decision-makers on the importance of wise use of Urban Wetlands and conservation to improving livelihood for urban dwellers.

Keywords: wetlands, tanzania, dar es salaam, climate-change, and wetlands, livelihood

Procedia PDF Downloads 171

Authors: M. Valentini, D. Melisi, M. A. Nitti, R A. Picca, M. C. Sportelli, E. Bonerba, G. Casamassima, N. Cioffi, L. Sabbatini, G. Tantillo, A. Valentini

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In recent years antimicrobial coatings are receiving increasing attention due to their high demand in medical applications as well as in healthcare and hygiene. Research and technology are constantly involved to develop advanced finishing which can provide bacteriostatic growth without compromising the other typical properties of a textile as durability and non-toxicity, just to cite a few. Here we report on the antimicrobial coatings obtained, at room temperature and without the use of solvents, by means of the ion beam co-sputtering technique of an Ag target and a polytetrafluoroethylene one. In particular, such method allows to conjugate the well-known antimicrobial action of silver with the anti-stain and water-repellent properties of the fluoropolymer. Moreover, different Ag nanoparticle loadings (φ) were prepared by tuning the material deposition conditions achieving a fine control on film thickness and their antimicrobial/anti-stain properties.

Keywords: antimicrobial, ion beam sputtering, nanocoatings, anti-stain

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Authors: Hamza Nejib, Okba Taouali

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This paper presents two of the most knowing kernel adaptive filtering (KAF) approaches, the kernel least mean squares and the kernel recursive least squares, in order to predict a new output of nonlinear signal processing. Both of these methods implement a nonlinear transfer function using kernel methods in a particular space named reproducing kernel Hilbert space (RKHS) where the model is a linear combination of kernel functions applied to transform the observed data from the input space to a high dimensional feature space of vectors, this idea known as the kernel trick. Then KAF is the developing filters in RKHS. We use two nonlinear signal processing problems, Mackey Glass chaotic time series prediction and nonlinear channel equalization to figure the performance of the approaches presented and finally to result which of them is the adapted one.

Keywords: online prediction, KAF, signal processing, RKHS, Kernel methods, KRLS, KLMS

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Authors: Su Yi Ming, Hou Ying, Zou Guang Ping

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Metal-net rubber is a new dry friction damping material, compared with the traditional metal rubber, which has high mechanization degree, and the mechanical performance of metal-net rubber is more stable. Through the sine sweep experiment and random vibration experiment of metal-net rubber vibration isolator, the influence of several important factors such as the lines slope, relative density and wire diameter on the transfer rate, natural frequency and root-mean-square response acceleration of metal-net rubber vibration isolation system, were studied through the method of control variables. Also, several relevant change curves under different vibration levels were derived, and the effects of vibration level on the natural frequency and root-mean-square response acceleration were analyzed through the curves.

Keywords: metal-net rubber vibration isolator, relative density, vibration level, wire diameter

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Authors: Fan Gao, Lior Pachter

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The primary tool currently used to pre-process 10X Chromium single-cell ATAC-seq data is Cell Ranger, which can take very long to run on standard datasets. To facilitate rapid pre-processing that enables reproducible workflows, we present a suite of tools called scATAK for pre-processing single-cell ATAC-seq data that is 15 to 18 times faster than Cell Ranger on mouse and human samples. Our tool can also calculate chromatin interaction potential matrices, and generate open chromatin signal and interaction traces for cell groups. We use scATAK tool to explore the chromatin regulatory landscape of a healthy adult human brain and unveil cell-type specific features, and show that it provides a convenient and computational efficient approach for pre-processing single-cell ATAC-seq data.

Keywords: single-cell, ATAC-seq, bioinformatics, open chromatin landscape, chromatin interactome

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Authors: S. Levitsky, R. Bergman

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Fluid rheology may have essential impact on sound propagation in a liquid-filled pipe, especially, in a low frequency range. Rheological parameters of liquid are temperature-sensitive, which ultimately results in a temperature dependence of the wave speed and attenuation in the waveguide. The study is devoted to modeling of this effect at sound propagation in an elastic pipe with polymeric liquid, described by generalized Maxwell model with non-zero high-frequency viscosity. It is assumed that relaxation spectrum is distributed according to the Spriggs law; temperature impact on the liquid rheology is described on the basis of the temperature-superposition principle and activation theory. The dispersion equation for the waveguide, considered as a thin-walled tube with polymeric solution, is obtained within a quasi-one-dimensional formulation. Results of the study illustrate the influence of temperature on sound propagation in the system.

Keywords: elastic tube, sound propagation, temperature effect, viscoelastic liquid

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Authors: Moser Stephan, Lukasser Gerald, Weitlaner Robert

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Urban structures will be used more intensively in the future through redensification or new planned districts with high building densities. Especially, to achieve positive energy balances like requested for Positive Energy Districts (PED) the single use of roofs is not sufficient for dense urban areas. However, the increasing share of window significantly reduces the facade area available for use in PV generation. Through the use of PV technology at other building components, such as external venetian blinds, onsite generation can be maximized and standard functionalities of this product can be positively extended. While offering advantages in terms of infrastructure, sustainability in the use of resources and efficiency, these systems require an increased optimization in planning and control strategies of buildings. External venetian blinds with PV technology require an intelligent control concept to meet the required demands such as maximum power generation, glare prevention, high daylight autonomy, avoidance of summer overheating but also use of passive solar gains in wintertime. Today, geometric representation of outdoor spaces and at the building level, three-dimensional geometric information is available for planning with Building Information Modeling (BIM). In a research project, a web application which is called HELLA DECART was developed to provide this data structure to extract the data required for the simulation from the BIM models and to make it usable for the calculations and coupled simulations. The investigated object is uploaded as an IFC file to this web application and includes the object as well as the neighboring buildings and possible remote shading. This tool uses a ray tracing method to determine possible glare from solar reflections of a neighboring building as well as near and far shadows per window on the object. Subsequently, an annual estimate of the sunlight per window is calculated by taking weather data into account. This optimized daylight assessment per window provides the ability to calculate an estimation of the potential power generation at the integrated PV on the venetian blind but also for the daylight and solar entry. As a next step, these results of the calculations as well as all necessary parameters for the thermal simulation can be provided. The overall aim of this workflow is to advance the coordination between the BIM model and coupled building simulation with the resulting shading and daylighting system with the artificial lighting system and maximum power generation in a control system. In the research project Powershade, an AI based control concept for PV integrated façade elements with coupled simulation results is investigated. The developed automated workflow concept in this paper is tested by using an office living lab at the HELLA company.

Keywords: BIPV, building simulation, optimized control strategy, planning tool

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Authors: T. Angeline Priyanka, R. Ganesan

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Recent trends in microelectronics technology have gradually changed the strategies used in very large scale integration (VLSI) circuits. Complementary Metal Oxide Semiconductor (CMOS) technology has been the industry standard for implementing VLSI device for the past two decades, but due to scale-down issues of ultra-low dimension achievement is not achieved so far. Hence it paved a way for Quantum Cellular Automata (QCA). It is only one of the many alternative technologies proposed as a replacement solution to the fundamental limit problem that CMOS technology will impose in the years to come. In this brief, presented a new adder that possesses high speed of operation occupying less area is proposed. This adder is designed especially for error tolerant application. Hence in the proposed adder, the overall area (cell count) and simulation time are reduced by 88 and 73 percent respectively. Various results of the proposed adder are shown and described.

Keywords: quantum cellular automata, carry look ahead adder, ripple carry adder, lossy application, majority gate, crossover

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Authors: Jan Busch, Maurice Schmidt, Peter Nyhuis

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The change of conditions for production companies in high-wage countries is characterized by the globalization of competition and the transition of a supplier´s to a buyer´s market. The companies need to face the challenges of reacting flexibly to these changes. Due to the significant and increasing degree of automation, assembly has become the most expensive production process. Regarding the reduction of production cost, assembly consequently offers a considerable rationalizing potential. Therefore, an aerodynamic feeding system has been developed at the Institute of Production Systems and Logistics (IFA), Leibniz Universitaet Hannover. In former research activities, this system has been enabled to adjust itself using genetic algorithm. The longer the genetic algorithm is executed the better is the feeding quality. In this paper, the relation between the system´s setting time and the feeding quality is observed and a function which enables the user to achieve the minimum of the total feeding time is presented.

Keywords: aerodynamic feeding system, batch size, optimisation, setting time

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Authors: H. V. Jayaprakash, P. V. Krupakara

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This paper deals with the high corrosion resistance developed by the metal matrix composites when compared with that of matrix alloy by open circuit potential test. Matrix selected is ZA-27 and reinforcement selected is red mud particulates, which is a ceramic material. The composites are prepared using liquid melt metallurgy technique using vortex method. Preheated but uncoated red mud particulates are added to the melt. Metal matrix composites containing 2, 4 and 6 weight percentage of red mud are casted. Matrix was also casted in the same way for comparison. Specimen are fabricated according to ASTM standards. The corrodents used for the tests were 0.025, 0.05 and 0.1 molar sodium hydroxide solutions. They are subjected to Open Circuit Potential studies and weight loss corrosion tests. Corrosion rate was found to be decreased with increase in exposure time in both experiments. Effect of exposure time and presence of increased percentage of reinforcement red mud is discussed in detail.

Keywords: composites, vortex, particulates, red mud

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Authors: Mahla Zabet, Navid Zanganeh, Hafez Balavi, Farbod Sharif

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Electrodeposition is a method for applying coatings with uniform thickness on complex objects. A conductive surface can be produced using the electrical current in this method. Carbon nanotubes are known to have high electrical conductivity and mechanical properties. In this report, NH2-multiwalled carbon nanotubes (MWCNTs) were used in epoxy resin with different weight percent. The weight percent of incorporated MWCNTS into the matrix was changed in the range of 0.6-3.6 wt% to obtain a series of electrocoatings. The electrocoats were then applied on steel substrates by a cathodic electrodeposition technique. Scanning electron microscopy (SEM) and optical microscopy were used to characterize the electrocoated films. The results illustrated the increase in conductivity by increasing of MWCNT load. However, at the percolation threshold, throwing power was dropped with increase in recoating ability.

Keywords: electrodeposition, carbon nanotube, electrical conductivity, throwing power

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Authors: Maciej Szeląg, Stanisław Fic

Abstract:

The impact of elevated temperatures on the construction materials manifests in change of their physical and mechanical characteristics. Stresses and thermal deformations that occur inside the volume of the material cause its progressive degradation as temperature increase. Finally, the reactions and transformations of multiphase structure of cementitious composite cause its complete destruction. A particularly dangerous phenomenon is the impact of thermal shock – a sudden high temperature load. The thermal shock leads to a high value of the temperature gradient between the outer surface and the interior of the element in a relatively short time. The result of mentioned above process is the formation of the cracks and scratches on the material’s surface and inside the material. The article describes the use of computer image analysis techniques to identify and assess the structure of the cluster cracks on the surfaces of modified cement pastes, caused by thermal shock. Four series of specimens were tested. Two Portland cements were used (CEM I 42.5R and CEM I 52,5R). In addition, two of the series contained metakaolinite as a replacement for 10% of the cement content. Samples in each series were made in combination of three w/b (water/binder) indicators of respectively 0.4; 0.5; 0.6. Surface cracks of the samples were created by a sudden temperature load at 200°C for 4 hours. Images of the cracked surfaces were obtained via scanning at 1200 DPI; digital processing and measurements were performed using ImageJ v. 1.46r software. In order to examine the cracked surface of the cement paste as a system of closed clusters – the dispersal systems theory was used to describe the structure of cement paste. Water is used as the dispersing phase, and the binder is used as the dispersed phase – which is the initial stage of cement paste structure creation. A cluster itself is considered to be the area on the specimen surface that is limited by cracks (created by sudden temperature loading) or by the edge of the sample. To describe the structure of cracks two stereological parameters were proposed: A ̅ – the cluster average area, L ̅ – the cluster average perimeter. The goal of this study was to compare the investigated stereological parameters with the mechanical properties of the tested specimens. Compressive and tensile strength testes were carried out according to EN standards. The method used in the study allowed the quantitative determination of defects occurring in the examined modified cement pastes surfaces. Based on the results, it was found that the nature of the cracks depends mainly on the physical parameters of the cement and the intermolecular interactions on the dispersal environment. Additionally, it was noted that the A ̅/L ̅ relation of created clusters can be described as one function for all tested samples. This fact testifies about the constant geometry of the thermal cracks regardless of the presence of metakaolinite, the type of cement and the w/b ratio.

Keywords: cement paste, cluster cracks, elevated temperature, image analysis, metakaolinite, stereological parameters

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