Search results for: mass per unit area
3342 Experimental Analysis of the Influence of Water Mass Flow Rate on the Performance of a CO2 Direct-Expansion Solar Assisted Heat Pump
Authors: Sabrina N. Rabelo, Tiago de F. Paulino, Willian M. Duarte, Samer Sawalha, Luiz Machado
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Energy use is one of the main indicators for the economic and social development of a country, reflecting directly in the quality of life of the population. The expansion of energy use together with the depletion of fossil resources and the poor efficiency of energy systems have led many countries in recent years to invest in renewable energy sources. In this context, solar-assisted heat pump has become very important in energy industry, since it can transfer heat energy from the sun to water or another absorbing source. The direct-expansion solar assisted heat pump (DX-SAHP) water heater system operates by receiving solar energy incident in a solar collector, which serves as an evaporator in a refrigeration cycle, and the energy reject by the condenser is used for water heating. In this paper, a DX-SAHP using carbon dioxide as refrigerant (R744) was assembled, and the influence of the variation of the water mass flow rate in the system was analyzed. The parameters such as high pressure, water outlet temperature, gas cooler outlet temperature, evaporator temperature, and the coefficient of performance were studied. The mainly components used to assemble the heat pump were a reciprocating compressor, a gas cooler which is a countercurrent concentric tube heat exchanger, a needle-valve, and an evaporator that is a copper bare flat plate solar collector designed to capture direct and diffuse radiation. Routines were developed in the LabVIEW and CoolProp through MATLAB software’s, respectively, to collect data and calculate the thermodynamics properties. The range of coefficient of performance measured was from 3.2 to 5.34. It was noticed that, with the higher water mass flow rate, the water outlet temperature decreased, and consequently, the coefficient of performance of the system increases since the heat transfer in the gas cooler is higher. In addition, the high pressure of the system and the CO2 gas cooler outlet temperature decreased. The heat pump using carbon dioxide as a refrigerant, especially operating with solar radiation has been proven to be a renewable source in an efficient system for heating residential water compared to electrical heaters reaching temperatures between 40 °C and 80 °C.
Keywords: Water mass flow rate, R-744, heat pump, solar evaporator, water heater.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10983341 Shaking Force Balancing of Mechanisms: An Overview
Authors: Vigen Arakelian
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The balancing of mechanisms is a well-known problem in the field of mechanical engineering because the variable dynamic loads cause vibrations, as well as noise, wear and fatigue of the machines. A mechanical system with unbalance shaking force and shaking moment transmits substantial vibration to the frame. Therefore, the objective of the balancing is to cancel or reduce the variable dynamic reactions transmitted to the frame. The resolution of this problem consists in the balancing of the shaking force and shaking moment. It can be fully or partially, by internal mass redistribution via adding counterweights or by modification of the mechanism's architecture via adding auxiliary structures. The balancing problems are of continue interest to researchers. Several laboratories around the world are very active in this area and new results are published regularly. However, despite its ancient history, mechanism balancing theory continues to be developed and new approaches and solutions are constantly being reported. Various surveys have been published that disclose particularities of balancing methods. The author believes that this is an appropriate moment to present a state of the art of the shaking force balancing studies completed by new research results. This paper presents an overview of methods devoted to the shaking force balancing of mechanisms, as well as the historical aspects of the origins and the evolution of the balancing theory of mechanisms.
Keywords: Inertia forces, shaking forces, balancing, dynamics.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 5323340 Physicochemical Stability of Pulse Spreads during Storage after Sous Vide Treatment and High Pressure Processing
Authors: Asnate Kirse, Daina Karklina, Sandra Muizniece-Brasava, Ruta Galoburda
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Pulses are high in plant protein and dietary fiber, and contain slowly digestible starches. Innovative products from pulses could increase their consumption and benefit consumer health. This study was conducted to evaluate physicochemical stability of processed cowpea (Vigna unguiculata (L.) Walp. cv. Fradel) and maple pea (Pisum sativum var. arvense L. cv. Bruno) spreads at 5 °C temperature during 62-day storage. Physicochemical stability of pulse spreads was compared after sous vide treatment (80 °C/15 min) and high pressure processing (700 MPa/10 min/20 °C). Pulse spreads were made by homogenizing cooked pulses in a food processor together with salt, citric acid, oil, and bruschetta seasoning. A total of four different pulse spreads were studied: Cowpea spread without and with seasoning, maple pea spread without and with seasoning. Transparent PA/PE and light proof PET/ALU/PA/PP film pouches were used for packaging of pulse spreads under vacuum. The parameters investigated were pH, water activity and mass losses. Pulse spreads were tested on days 0, 15, 29, 42, 50, 57 and 62. The results showed that sous-vide treatment and high pressure processing had an insignificant influence on pH, water activity and mass losses after processing, irrespective of packaging material did not change (p>0.1). pH and water activity of sous-vide treated and high pressure processed pulse spreads in different packaging materials proved to be stable throughout the storage. Mass losses during storage accounted to 0.1% losses. Chosen sous-vide treatment and high pressure processing regimes and packaging materials are suitable to maintain consistent physicochemical quality of the new products during 62-day storage.
Keywords: Cowpea, flexible packaging, maple pea, pH, water activity.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12743339 Increasing Fishery Economic Added Value through Post Fishing Program: Cold Storage Program
Authors: Indrijuli Magsari Putri, Dicky R. Munaf
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The purpose of this paper is to guide the effort in improving the economic added value of Indonesian fisheries product through post fishing program, which is cold storage program. Indonesia's fisheries potential has been acknowledged by the world. FAO (2009) stated that Indonesia is one of the tenth highest producers of fishery products in the world. Based on BPS (Statistics Indonesia data), the national fisheries production in 2011 reached 5.714 million tons, which 93.55% came from marine fisheries and 6.45% from open waters. Indonesian territory consist of 2/3 of Indonesian waters, has given enormous benefits for Indonesia, especially fishermen. To improve the economic level of fishermen requires efforts to develop fisheries business unit. On of the efforts is by improving the quality of products which are marketed in the regional and international levels. It is certainly need the support of the existence of various fishery facilities (infrastructure to superstructure), one of which is cold storage. Given the many benefits of cold storage as a means of processing of fishery resources, Indonesia Maritime Security Coordinating Board (IMSCB) as one of the maritime institutions for maritime security and safety, has a program to empower the coastal community through encourages the development of cold storage in the middle and lower fishery business unit. The development of cold storage facilities which able to run its maximum role requires synergistic efforts of various parties.
Keywords: Cold Storage, Fish, Regulation.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 21053338 Automatic Generation Control of Multi-Area Electric Energy Systems Using Modified GA
Authors: Gayadhar Panda, Sidhartha Panda, C. Ardil
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A modified Genetic Algorithm (GA) based optimal selection of parameters for Automatic Generation Control (AGC) of multi-area electric energy systems is proposed in this paper. Simulations on multi-area reheat thermal system with and without consideration of nonlinearity like governor dead band followed by 1% step load perturbation is performed to exemplify the optimum parameter search. In this proposed method, a modified Genetic Algorithm is proposed where one point crossover with modification is employed. Positional dependency in respect of crossing site helps to maintain diversity of search point as well as exploitation of already known optimum value. This makes a trade-off between exploration and exploitation of search space to find global optimum in less number of generations. The proposed GA along with decomposition technique as developed has been used to obtain the optimum megawatt frequency control of multi-area electric energy systems. Time-domain simulations are conducted with trapezoidal integration along with decomposition technique. The superiority of the proposed method over existing one is verified from simulations and comparisons.
Keywords: Automatic Generation Control (AGC), Reheat, Proportional Integral (PI) controller, Dead Band, Genetic Algorithm(GA).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26493337 Street Network in Bandung City, Indonesia: Comparison between City Center and New Commercial Area
Authors: Siska Soesanti, Norihiro Nakai
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Bandung city center can be deemed as economic, social and cultural center. However the city center suffers from deterioration. The retail activities tend to shift outward the city center. Numerous idyllic residences changed into business premises in two villages situated in the north part of the city during 1990s, especially after a new highway and flyover opened. According to space syntax theory, the pattern of spatial integration in the urban grid is a prime determinant of movement patterns in the system. The syntactic analysis results show the flyover has insignificant influence on street network in the city center. However the flyover has been generating a major difference in the new commercial area since it has become relatively as strategic as the city center. Besides street network, local government policy, rapid private motorization and particular condition of each site also played important roles in encouraging the current commercial areas to flourish.
Keywords: City center, commercial area, space syntax, street network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 18093336 Influence of [Emim][OAc] and Water on Gelatinization Process and Interactions with Starch
Authors: Shajaratuldur Ismail, Nurlidia Mansor, Zakaria Man
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Thermoplastic starch (TPS) plasticized by 1-ethyl-3-methylimidazolium acetate [Emim][OAc] were obtained through gelatinization process. The gelatinization process occurred in the presence of water and [Emim][OAc] as plasticizer at high temperature (90˚C). The influence of [Emim][OAc] and water on the gelatinization and interactions with starch have been studied over a range of compositions. The homogenous mass was obtained for the samples containing 35, 40 and 43.5 % of water contents which showed that water plays important role in gelatinization process. Detailed IR spectroscopy analysis showed decrease in hydrogen bonding intensity and strong interaction between acetate anion in [Emim][OAc] and starch hydroxyl groups in the presence of [Emim][OAc]. Starch-[Emim][OAc]-water mixture at 10-3-8.7 presented homogenous mass, less hydrogen bonding intensity and strong interaction between acetate anion in [Emim][OAc] and starch hydroxyl groups.
Keywords: Starch, ionic liquid, 1-ethyl-3-methylimidazolium acetate, plasticizer, gelatinization, IR spectroscopy.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8933335 Design of Low Power and High Speed Digital IIR Filter in 45nm with Optimized CSA for Digital Signal Processing Applications
Authors: G. Ramana Murthy, C. Senthilpari, P. Velrajkumar, Lim Tien Sze
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In this paper, a design methodology to implement low-power and high-speed 2nd order recursive digital Infinite Impulse Response (IIR) filter has been proposed. Since IIR filters suffer from a large number of constant multiplications, the proposed method replaces the constant multiplications by using addition/subtraction and shift operations. The proposed new 6T adder cell is used as the Carry-Save Adder (CSA) to implement addition/subtraction operations in the design of recursive section IIR filter to reduce the propagation delay. Furthermore, high-level algorithms designed for the optimization of the number of CSA blocks are used to reduce the complexity of the IIR filter. The DSCH3 tool is used to generate the schematic of the proposed 6T CSA based shift-adds architecture design and it is analyzed by using Microwind CAD tool to synthesize low-complexity and high-speed IIR filters. The proposed design outperforms in terms of power, propagation delay, area and throughput when compared with MUX-12T, MCIT-7T based CSA adder filter design. It is observed from the experimental results that the proposed 6T based design method can find better IIR filter designs in terms of power and delay than those obtained by using efficient general multipliers.
Keywords: CSA Full Adder, Delay unit, IIR filter, Low-Power, PDP, Parametric Analysis, Propagation Delay, Throughput, VLSI.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 38003334 Enhanced Efficacy of Kinetic Power Transform for High-Speed Wind Field
Authors: Nan-Chyuan Tsai, Chao-Wen Chiang, Bai-Lu Wang
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The three-time-scale plant model of a wind power generator, including a wind turbine, a flexible vertical shaft, a Variable Inertia Flywheel (VIF) module, an Active Magnetic Bearing (AMB) unit and the applied wind sequence, is constructed. In order to make the wind power generator be still able to operate as the spindle speed exceeds its rated speed, the VIF is equipped so that the spindle speed can be appropriately slowed down once any stronger wind field is exerted. To prevent any potential damage due to collision by shaft against conventional bearings, the AMB unit is proposed to regulate the shaft position deviation. By singular perturbation order-reduction technique, a lower-order plant model can be established for the synthesis of feedback controller. Two major system parameter uncertainties, an additive uncertainty and a multiplicative uncertainty, are constituted by the wind turbine and the VIF respectively. Frequency Shaping Sliding Mode Control (FSSMC) loop is proposed to account for these uncertainties and suppress the unmodeled higher-order plant dynamics. At last, the efficacy of the FSSMC is verified by intensive computer and experimental simulations for regulation on position deviation of the shaft and counter-balance of unpredictable wind disturbance.Keywords: Sliding Mode Control, Singular Perturbation, Variable Inertia Flywheel.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14493333 A Novel Computer Vision Method for Evaluating Deformations of Fibers Cross Section in False Twist Textured Yarns
Authors: Dariush Semnani, Mehdi Ahangareianabhari, Hossein Ghayoor
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In recent five decades, textured yarns of polyester fiber produced by false twist method are the most important and mass-produced manmade fibers. There are many parameters of cross section which affect the physical and mechanical properties of textured yarns. These parameters are surface area, perimeter, equivalent diameter, large diameter, small diameter, convexity, stiffness, eccentricity, and hydraulic diameter. These parameters were evaluated by digital image processing techniques. To find trends between production criteria and evaluated parameters of cross section, three criteria of production line have been adjusted and different types of yarns were produced. These criteria are temperature, drafting ratio, and D/Y ratio. Finally the relations between production criteria and cross section parameters were considered. The results showed that the presented technique can recognize and measure the parameters of fiber cross section in acceptable accuracy. Also, the optimum condition of adjustments has been estimated from results of image analysis evaluation.Keywords: Computer Vision, Cross Section Analysis, Fibers Deformation, Textured Yarn
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 16393332 Designing a Novel General Sorting Network Constructor Using Artificial Evolution
Authors: Michal Bidlo, Radek Bidlo, Lukas Sekanina
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A method is presented for the construction of arbitrary even-input sorting networks exhibiting better properties than the networks created using a conventional technique of the same type. The method was discovered by means of a genetic algorithm combined with an application-specific development. Similarly to human inventions in the area of theoretical computer science, the evolved invention was analyzed: its generality was proven and area and time complexities were determined.Keywords: Development, genetic algorithm, program, sorting network.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12783331 Effect of Fine-Ground Ceramic Admixture on Early Age Properties of Cement Paste
Authors: Z. Pavlík, M. Pavlíková, P. Volfová, M. Keppert, R. Černý
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Properties of cement pastes with fine-ground ceramics used as an alternative binder replacing Portland cement up to 20% of its mass are investigated. At first, the particle size distribution of cement and fine-ground ceramics is measured using laser analyser. Then, the material properties are studied in the early hardening period up to 28 days. The hydration process of studied materials is monitored by electrical conductivity measurement using TDR sensors. The changes of materials- structures within the hardening are observed using pore size distribution measurement. The compressive strength measurements are done as well. Experimental results show that the replacement of Portland cement by fine-ground ceramics in the amount of up to 20% by mass is acceptable solution from the mechanical point of view. One can also assume similar physical properties of designed materials to the reference material with only Portland cement as binder.Keywords: Fine-ground ceramics, cement pastes, early age properties, mechanical properties, pore size distribution, electrical conductivity measurement.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15793330 Automatic Generation Control Design Based on Full State Vector Feedback for a Multi-Area Energy System Connected via Parallel AC/DC Lines
Authors: Gulshan Sharma
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This article presents the design of optimal automatic generation control (AGC) based on full state feedback control for a multi-area interconnected power system. An extra high voltage AC transmission line in parallel with a high voltage DC link is considered as an area interconnection between the areas. The optimal AGC are designed and implemented in the wake of 1% load perturbation in one of the areas and the system dynamic response plots for various system states are obtained to investigate the system dynamic performance. The pattern of closed-loop eigenvalues are also determined to analyze the system stability. From the investigations carried out in the work, it is revealed that the dynamic performance of the system under consideration has an appreciable improvement when a high voltage DC line is paralleled with an extra high voltage AC line as an interconnection between the areas. The investigation of closed-loop eigenvalues reveals that the system stability is ensured in all case studies carried out with the designed optimal AGC.
Keywords: Automatic generation control, area control error, DC link, optimal AGC regulator, closed-loop eigenvalues.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8143329 The Use of Scuba Diving Tourism for Marine Protected Area Management
Authors: L. Mota, O. Frausto
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Marine Protected Areas can benefit from nature based tourism, monitoring environmental impacts and also become target for human presence. From more than 3 million tourists visiting Cozumel Island every year, an average of 2,8 million arrive by cruise ship, and 41% are estimated to have motivation for water activities. The destination is relying so much on the tourism activity, that scuba diving and snorkeling in the National Park Reef of Cozumel sustain the major economic activity. In order to achieve the sustainable development indicator designed for regional environmental development, the PNAC offers a training course to tourism providers to access the protected area. This way, the update of the last 5 years of such training is directed to diving staff, boat crew and professionals, making them able to assist in managing the natural resource. Moreover, the case study is an example to be used for raising awareness among tourists visiting protected areas.
Keywords: Education, Marine Protected Area, scuba diving, sustainability, tourism.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25173328 Facility Location Problem in Emergency Logistic
Authors: Yousef Abu Nahleh, Arun Kumar, Fugen Daver
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Facility location is one of the important problems affecting the relief operations. The location model in this paper is motivated by arranging the flow of relief materials from the main warehouse to continent warehouse and further to regional warehouse and from these to the disaster area. This flow makes the relief organization always ready to deal with the disaster situation during shortest possible time. The main purpose of this paper is merge the concept of just in time and the campaign system in emergency supply chain,so that when the disaster happens the affected country can request help from the nearest regional warehouse, which will supply the relief material and the required stuff to support and assist the victims in the disaster area. Furthermore, the regional warehouse places an order to the continent warehouse to replenish the material that is distributed to the disaster area. This way they will always be ready to respond to any type of disaster.
Keywords: Facility location, Center-of-Gravity Technique, Humanitarian relief, emergency supply chain.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 37853327 Mechanical Strengths of Self-Compacting Mortars Prepared with the Pozzolanic Cement in Aggressive Environments
Authors: M. Saidi, I. Djefour, F. Ait Medjber, A. Melouane, A. Gacem
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The objective of this research is to study the physical and mechanical properties and durability of self-compacting mortars prepared by substituting a part of cement up to a percentage of 30% pozzolan according to different Blaine specific surface area (SSB1=7000 cm2/g and SSB=9000 cm2/g)). Order to evaluate durability, mortars were subjected to chemical attacks in various aggressive environments, a solution of a mixture of nitric acid and ammonium nitrate (HNO3 + NH4NO3) and a magnesium sulfate salt solution (MgSO4)) with a concentration of 10%, for a period of one month. This study is complemented by a comparative study of the durability of mortars elaborated with sulphate resistant cement (SRC). The results show that these mortars develop long-term, mechanical and chemical resistance better than mortars based Portland cement with 5% gypsum (CEM 1) and SRC. We found that the mass losses are lowest in mortars elaborated with pozzolanic cement (30% substitution with SSB2) in both of chemical attack solutions (3.28% in the solution acid and 1.16% in the salt solution) and the compressive strength gains of 14.68% and 8.5% respectively in the two media. This is due to the action of pozzolan which fixes portlandite to form hydrated calcium silicate (CSH) from the hydration of tricalcic silicate (C3S).
Keywords: Aggressive environments, durability, mechanical strengths, pozzolanic cement, self-compacting mortar.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9633326 Intelligent Automatic Generation Control of Two Area Interconnected Power System using Hybrid Neuro Fuzzy Controller
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This paper presents the development and application of an adaptive neuro fuzzy inference system (ANFIS) based intelligent hybrid neuro fuzzy controller for automatic generation control (AGC) of two-area interconnected thermal power system with reheat non linearity. The dynamic response of the system has been studied for 1% step load perturbation in area-1. The performance of the proposed neuro fuzzy controller is compared against conventional proportional-integral (PI) controller, state feedback linear quadratic regulator (LQR) controller and fuzzy gain scheduled proportionalintegral (FGSPI) controller. Comparative analysis demonstrates that the proposed intelligent neuro fuzzy controller is the most effective of all in improving the transients of frequency and tie-line power deviations against small step load disturbances. Simulations have been performed using Matlab®.
Keywords: Automatic generation control, ANFIS, LQR, Hybrid neuro fuzzy controller
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 26723325 Production Line Layout Planning Based on Complexity Measurement
Authors: Guoliang Fan, Aiping Li, Nan Xie, Liyun Xu, Xuemei Liu
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Mass customization production increases the difficulty of the production line layout planning. The material distribution process for variety of parts is very complex, which greatly increases the cost of material handling and logistics. In response to this problem, this paper presents an approach of production line layout planning based on complexity measurement. Firstly, by analyzing the influencing factors of equipment layout, the complexity model of production line is established by using information entropy theory. Then, the cost of the part logistics is derived considering different variety of parts. Furthermore, the function of optimization including two objectives of the lowest cost, and the least configuration complexity is built. Finally, the validity of the function is verified in a case study. The results show that the proposed approach may find the layout scheme with the lowest logistics cost and the least complexity. Optimized production line layout planning can effectively improve production efficiency and equipment utilization with lowest cost and complexity.
Keywords: Production line, layout planning, complexity measurement, optimization, mass customization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 10773324 Effect of Assumptions of Normal Shock Location on the Design of Supersonic Ejectors for Refrigeration
Authors: Payam Haghparast, Mikhail V. Sorin, Hakim Nesreddine
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The complex oblique shock phenomenon can be simply assumed as a normal shock at the constant area section to simulate a sharp pressure increase and velocity decrease in 1-D thermodynamic models. The assumed normal shock location is one of the greatest sources of error in ejector thermodynamic models. Most researchers consider an arbitrary location without justifying it. Our study compares the effect of normal shock place on ejector dimensions in 1-D models. To this aim, two different ejector experimental test benches, a constant area-mixing ejector (CAM) and a constant pressure-mixing (CPM) are considered, with different known geometries, operating conditions and working fluids (R245fa, R141b). In the first step, in order to evaluate the real value of the efficiencies in the different ejector parts and critical back pressure, a CFD model was built and validated by experimental data for two types of ejectors. These reference data are then used as input to the 1D model to calculate the lengths and the diameters of the ejectors. Afterwards, the design output geometry calculated by the 1D model is compared directly with the corresponding experimental geometry. It was found that there is a good agreement between the ejector dimensions obtained by the 1D model, for both CAM and CPM, with experimental ejector data. Furthermore, it is shown that normal shock place affects only the constant area length as it is proven that the inlet normal shock assumption results in more accurate length. Taking into account previous 1D models, the results suggest the use of the assumed normal shock location at the inlet of the constant area duct to design the supersonic ejectors.
Keywords: 1D model, constant area-mixing, constant pressure-mixing, normal shock location, ejector dimensions.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 9423323 Thermohydraulic Performance of Double Flow Solar Air Heater with Corrugated Absorber
Authors: S. P. Sharma, Som Nath Saha
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This paper deals with the analytical investigation of thermal and thermohydraulic performance of double flow solar air heaters with corrugated and flat plate absorber. A mathematical model of double flow solar air heater has been presented, and a computer program in C++ language is developed to estimate the outlet temperature of air for the evaluation of thermal and thermohydraulic efficiency by solving the governing equations numerically using relevant correlations for heat transfer coefficients. The results obtained from the mathematical model is compared with the available experimental results and it is found to be reasonably good. The results show that the double flow solar air heaters have higher efficiency than conventional solar air heater, although the double flow corrugated absorber is superior to that of flat plate double flow solar air heater. It is also observed that the thermal efficiency increases with increase in mass flow rate; however, thermohydraulic efficiency increases with increase in mass flow rate up to a certain limit, attains the maximum value, then thereafter decreases sharply.
Keywords: Corrugated absorber, double flow, solar air heater, thermohydraulic efficiency.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 14913322 Mathematical Model of Smoking Time Temperature Effect on Ribbed Smoked Sheets Quality
Authors: Rifah Ediati, Jajang
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The quality of Ribbed Smoked Sheets (RSS) primarily based on color, dryness, and the presence or absence of fungus and bubbles. This quality is strongly influenced by the drying and fumigation process namely smoking process. Smoking that is held in high temperature long time will result scorched dark brown sheets, whereas if the temperature is too low or slow drying rate would resulted in less mature sheets and growth of fungus. Therefore need to find the time and temperature for optimum quality of sheets. Enhance, unmonitored heat and mass transfer during smoking process lead to high losses of energy balance. This research aims to generate simple empirical mathematical model describing the effect of smoking time and temperature to RSS quality of color, water content, fungus and bubbles. The second goal of study was to analyze energy balance during smoking process. Experimental study was conducted by measuring temperature, residence time and quality parameters of 16 sheets sample in smoking rooms. Data for energy consumption balance such as mass of fuel wood, mass of sheets being smoked, construction temperature, ambient temperature and relative humidity were taken directly along the smoking process. It was found that mathematical model correlating smoking temperature and time with color is Color = -169 - 0.184 T4 - 0.193 T3 - 0.160 0.405 T1 + T2 + 0.388 t1 +3.11 t2 + 3.92t3 + 0.215 t4 with R square 50.8% and with moisture is Moisture = -1.40-0.00123 T4 + 0.00032 T3 + 0.00260 T2 - 0.00292 T1 - 0.0105 t1 + 0.0290 t2 + 0.0452 t3 + 0.00061 t4 with R square of 49.9%. Smoking room energy analysis found useful energy was 27.8%. The energy stored in the material construction 7.3%. Lost of energy in conversion of wood combustion, ventilation and others were 16.6%. The energy flowed out through the contact of material construction with the ambient air was found to be the highest contribution to energy losses, it reached 48.3%.Keywords: RSS quality, temperature, time, smoking room, energy
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 27413321 Investigation Corn and Soybean Intercropping Advantages in Competition with Redroot Pigweed and Jimsonweed
Authors: M. Rezvani, F. Zaefarian, M. Aghaalikhani, H. Rahimian Mashhadi, E. Zand
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The spatial variation in plant species associated with intercropping is intended to reduce resource competition between species and increase yield potential. A field experiment was carried out on corn (Zea mays L.) and soybean (Glycine max L.) intercropping in a replacement series experiment with weed contamination consist of: weed free, infestation of redroot pigweed, infestation of jimsonweed and simultaneous infestation of redroot pigweed and jimsonweed in Karaj, Iran during 2007 growing season. The experimental design was a randomized complete block in factorial experiment with replicated thrice. Significant (P≤0.05) differences were observed in yield in intercropping. Corn yield was higher in intercropping, but soybean yield was significantly reduced by corn when intercropped. However, total productivity and land use efficiency were high under the intercropping system even in contamination of either species of weeds. Aggressivity of corn relative to soybean revealed the greater competitive ability of corn than soybean. Land equivalent ratio (LER) more than 1 in all treatments attributed to intercropping advantages and was highest in 50: 50 (corn/soybean) in weed free. These findings suggest that intercropping corn and soybean increase total productivity per unit area and improve land use efficiency. Considering the experimental findings, corn-soybean intercropping (50:50) may be recommended for yield advantage, more efficient utilization of resources, and weed suppression as a biological control.
Keywords: Corn, soybean, intercropping, redroot pigweed, jimsonweed.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 25903320 Distributed Manufacturing (DM) - Smart Units and Collaborative Processes
Authors: Hermann Kuehnle
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Applications of the Hausdorff space and its mappings into tangent spaces are outlined, including their fractal dimensions and self-similarities. The paper details this theory set up and further describes virtualizations and atomization of manufacturing processes. It demonstrates novel concurrency principles that will guide manufacturing processes and resources configurations. Moreover, varying levels of details may be produced by up folding and breaking down of newly introduced generic models. This choice of layered generic models for units and systems aspects along specific aspects allows research work in parallel to other disciplines with the same focus on all levels of detail. More credit and easier access are granted to outside disciplines for enriching manufacturing grounds. Specific mappings and the layers give hints for chances for interdisciplinary outcomes and may highlight more details for interoperability standards, as already worked on the international level. The new rules are described, which require additional properties concerning all involved entities for defining distributed decision cycles, again on the base of self-similarity. All properties are further detailed and assigned to a maturity scale, eventually displaying the smartness maturity of a total shopfloor or a factory. The paper contributes to the intensive ongoing discussion in the field of intelligent distributed manufacturing and promotes solid concepts for implementations of Cyber Physical Systems and the Internet of Things into manufacturing industry, like industry 4.0, as discussed in German-speaking countries.
Keywords: Autonomous unit, Networkability, Smart manufacturing unit, Virtualization.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 20673319 ROSA/LSTF Separate Effect Test on Natural Circulation under High Core Power Condition of Pressurized Water Reactor
Authors: Takeshi Takeda
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A separate effect test (SET) simulated natural circulation (NC) under high core power condition of a pressurized water reactor (PWR) utilizing the ROSA/LSTF (rig of safety assessment/large-scale test facility). The LSTF test results clarified the relationship between the primary loop mass inventory and the primary loop mass flow rate being dependent on the NC mode at a constant core power of 8% of the volumetric-scaled PWR nominal power. When the core power was 9% or more during reflux condensation, large-amplitude level oscillation in a form of slow fill and dump occurred in steam generator (SG) U-tubes. At 11% core power during reflux condensation, intermittent rise took place in the cladding surface temperature of simulated fuel rods. The RELAP5/MOD3.3 code indicated the insufficient prediction of the SG U-tube liquid level behavior during reflux condensation.Keywords: LSTF, natural circulation, core power, RELAP5.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 8283318 Identification of Lean Implementation Hurdles in Indian Industries
Authors: Bhim Singh
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Due to increased pressure from global competitors, manufacturing organizations are switching over to lean philosophies from traditional mass production. Lean manufacturing is a manufacturing philosophy which focuses on elimination of various types of wastes and creates maximum value for the end customers. Lean thinking aims to produce high quality products and services at the lowest possible cost with maximum customer responsiveness. Indian Industry is facing lot of problems in this transformation from traditional mass production to lean production. Through this paper an attempt has been made to identify various lean implementation hurdles in Indian industries with the help of a structured survey. Identified hurdles are grouped with the help of factor analysis and rated by calculating descriptive statistics. To show the effect of lean implementation hurdles a hypothesis “Organizations having higher level of lean implementation hurdles will have poor (negative) performance” has been postulated and tested using correlation matrix between performance parameters of the organizations and identified hurdles. The findings of the paper will be helpful to prepare road map to identify and eradicate the lean implementation hurdles.
Keywords: Factor analysis, global competition, lean implementation and lean hurdles.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 19963317 Employees- Perceptions and Expectations toward Corporate Social Responsibility: A Case Study of Private Company Employees in Bangkok Metropolitan Area
Authors: Natta Changchutoe
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This research aimed to study employees- perceptions and expectations toward their organization-s corporate social responsibility (CSR), to study the differences between employees- personal factors and level of perceptions and expectations toward CSR, and to study the relationship between employees- perceptions and expectations toward CSR. Purposive sampling and questionnaire were applied to collect information from 400 private company employees in Bangkok metropolitan area. The results revealed that employees had “high" level of perceptions and expectations toward CSR, of which the highest level were given on the area of “corporate governance and transparency". It was found that there was different level of expectations of employees with different period of employment, position and employment (by listed and non-listed companies). Employees of different age and period of employment also had different level of expectations. Employees- perceptions were correlated with their expectations toward CSR.
Keywords: Employees, Perceptions, Expectations, Corporate Social Responsibility (CSR).
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 41083316 Conflict of the Thai-Malaysian Gas Pipeline Project
Authors: Nopadol Burananuth
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This research was aimed to investigate (1) the relationship among local social movements, non-governmental Organization activities and state measures deployment; and (2) the effects of local social movements, non-governmental Organization activities, and state measures deployment on conflict of local people towards the Thai-Malaysian gas pipeline project. These people included 1,000 residents of the four districts in Songkhla province. The methods of data analysis consist of multiple regression analysis. The results of the analysis showed that: (1) local social movements depended on information, and mass communication; deployment of state measures depended on compromise, coordination, and mass communication; and (2) the conflict of local people depended on mobilization, negotiation, and campaigning for participation of people in the project. Thus, it is recommended that to successfully implement any government policy, consideration must be paid to the conflict of local people, mobilization, negotiation, and campaigning for people’s participation in the project.Keywords: Conflict, NGO activities, social movements, state measures.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 12243315 Evaluation of Stent Performances using FEA considering a Realistic Balloon Expansion
Authors: Won-Pil Park, Seung-Kwan Cho, Jai-Young Ko, Anders Kristensson, S.T.S. Al-Hassani, Han-Sung Kim, Dohyung Lim
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A number of previous studies were rarely considered the effects of transient non-uniform balloon expansion on evaluation of the properties and behaviors of stents during stent expansion, nor did they determine parameters to maximize the performances driven by mechanical characteristics. Therefore, in order to fully understand the mechanical characteristics and behaviors of stent, it is necessary to consider a realistic modeling of transient non-uniform balloon-stent expansion. The aim of the study is to propose design parameters capable of improving the ability of vascular stent through a comparative study of seven commercial stents using finite element analyses of a realistic transient non-uniform balloon-stent expansion process. In this study, seven representative commercialized stents were evaluated by finite element (FE) analysis in terms of the criteria based on the itemized list of Food and Drug Administration (FDA) and European Standards (prEN). The results indicate that using stents composed of opened unit cells connected by bend-shaped link structures and controlling the geometrical and morphological features of the unit cell strut or the link structure at the distal ends of stent may improve mechanical characteristics of stent. This study provides a better method at the realistic transient non-uniform balloon-stent expansion by investigating the characteristics, behaviors, and parameters capable of improving the ability of vascular stent.Keywords: Finite Element Analysis, Mechanical Characteristic, Transient Non-uniform Balloon-Stent Expansion, Vascular Stent.
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 17913314 Study on Numerical Simulation Applied to Moisture Buffering Design Method – The Case Study of Pine Wood in a Single Zone Residential Unit in Taiwan
Authors: Y.C. Yeh, Y.S. Tsay, C.M. Chiang
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A good green building design project, designers should consider not only energy consumption, but also healthy and comfortable needs of inhabitants. In recent years, the Taiwan government paid attentions on both carbon reduction and indoor air quality issues, which be presented in the legislation of Building Codes and other regulations. Taiwan located in hot and humid climates, dampness in buildings leads to significant microbial pollution and building damage. This means that the high temperature and humidity present a serious indoor air quality issue. The interactions between vapor transfers and energy fluxes are essential for the whole building Heat Air and Moisture (HAM) response. However, a simulation tool with short calculation time, property accuracy and interface is needed for practical building design processes. In this research, we consider the vapor transfer phenomenon of building materials as well as temperature and humidity and energy consumption in a building space. The simulation bases on the EMPD method, which was performed by EnergyPlus, a simulation tool developed by DOE, to simulate the indoor moisture variation in a one-zone residential unit based on the Effective Moisture Penetration Depth Method, which is more suitable for practical building design processes.
Keywords: Effective Moisture Penetration Depth Method, Moisture Buffering Effect, Interior Material, Green Material, EnergyPlus
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 15653313 An Information Theoretic Approach to Rescoring Peptides Produced by De Novo Peptide Sequencing
Authors: John R. Rose, James P. Cleveland, Alvin Fox
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Tandem mass spectrometry (MS/MS) is the engine driving high-throughput protein identification. Protein mixtures possibly representing thousands of proteins from multiple species are treated with proteolytic enzymes, cutting the proteins into smaller peptides that are then analyzed generating MS/MS spectra. The task of determining the identity of the peptide from its spectrum is currently the weak point in the process. Current approaches to de novo sequencing are able to compute candidate peptides efficiently. The problem lies in the limitations of current scoring functions. In this paper we introduce the concept of proteome signature. By examining proteins and compiling proteome signatures (amino acid usage) it is possible to characterize likely combinations of amino acids and better distinguish between candidate peptides. Our results strongly support the hypothesis that a scoring function that considers amino acid usage patterns is better able to distinguish between candidate peptides. This in turn leads to higher accuracy in peptide prediction.Keywords: Tandem mass spectrometry, proteomics, scoring, peptide, de novo, mutual information
Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1718