Статьи журнала - International Journal of Engineering and Manufacturing
Все статьи: 520
Start-up failures due to Quality Failures
Статья научная
Software start-ups are fundamentally different from traditional software development firms and boutique software services enterprises of all sizes. They develop software products with strict time and resource constraints and are focused on beating competitors to the market. They fail fast and often pivot their business models several times in their lifetimes. Their approach to designing, developing, testing, and shipping software products differs vastly from the established software engineering principles that emerged during the field’s earlier decades. One such principle is Software Quality Assurance. Start-ups tend to do away with procedures that ensure that their products are of the utmost quality. Instead, they focus on shipping their products to market as fast as possible, testing these products vis-a-vis real-life customers and use-cases, and eventually improving these products, repeating the process several times over. We hypothesize that this reluctance to adhere to software quality assurance principles can have adverse effects on the health of start-ups or their products. This paper investigates this hypothesis through over 20 questions presented to CEOs, CTOs, Technical Leads, and Product Managers of several start-ups. These questions focus on start-ups’ motivations, their levels of understanding and appreciation of software quality assurance principles, and the limitations they face due to time and resource constraints. Our research’s results indicate the surveyed start-ups’ problems are partially due to the absence of robust software quality assurance practices within their processes.
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Statics simulation of the buffer wastewater neutralization process
Статья научная
The pH value is a very common chemical measurement and is an indicator of water quality. For dilute solutions of strong acids and bases, the pH is related to their concentration, and therefore, it’s related to the required for neutralization dose of the reagent, a clear dependence. In this case, the pH value is quite reliable parameter to control the process of neutralization. However, when the wastewater components that have buffer properties, for example, mixtures of weak acids and bases and their salts in mixture with strong acids are present, the neutralization process is described already by a group of characteristics. In the last case, traditional automatic systems cannot cope with the qualitative pH regulation. The article is devoted to the mathematical statics model of a neutralization buffer of wastewater process development. Based on the formulated assumptions, this process was divided into stages. After considering the characteristics of each stage the mathematical model of the process was obtained. The theoretical research results are specified in the developed calculation algorithm of the total reagent dose which is required to neutralize the wastewater, which have strong and weak acids in its composition. The theoretical and practical research results were approbated in the design of automatic control system of the buffer wastewater neutralization process in the enterprise of low-waste technology.
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Step Motor Mode for Automobile Idle Adjuster
Статья научная
Automobile idle adjuster is mainly used to make the idle speed of engine be constant and reduce oil cost when automobile is in idle moving, which can increase idle speed and prevent engine from stopping. Automobile idle adjuster controls idle speed by controlling the mode of throttle valve channel. It also can increase idle speed automatically when the engine load is bigger. This can be happen when the air-conditioning unit, power steering or torque converter is introduced. In this paper, we mainly studied the effect, structure, working principle about step motor mode fro automobile idle adjuster. We also introduced the improvement about traditional automobile idle adjuster.
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Статья научная
The paper is devoted to the realization of scientific and technical ideas and knowledge in practice, and to the study and the structural analysis of the content of their transformation processes into innovation in technoparks. We show that the innovation processes are required to be analyzed and classified; their stages, as well as the system of indicators need to be improved. The need for the implementation of scientific and technological ideas is commented and considered as a process of innovation. The structure of the innovation process, its features and of stages are explained and classified in technoparks. The factors that affect the innovation processes are investigated; and the processes automation issues are considered, as well. Organizational and economical mechanisms used for the implementation of the innovation processes are analyzed and a number of recommendations are developed to improve the process.
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Structural Damage Identification Based on the Modal Data Change
Статья научная
This paper presents a method for structural damage identification based on the modal data change before and after the occurrence of damage. In this method, it is assumed that the reduction of structural stiffness due to damage as the summation of each elemental stiffness matrix multiplied by a damage coefficient. And then, the damage coefficient (damage extent) can be solved adversely from the vibration equation. Furthermore, the modal assurance criterion (MAC) is introduced to check the correlation of mode shapes between the damaged and the undamaged structure. An advantage of employing the MAC is that it can analyze the sensitivity of mode shapes to damage. To demonstrate the capability of the proposed method, an example of a six-span planar truss beam is used to verify the present method numerically. Results indicate that the proposed method is effective in locating single or multiple damage locations and quantifying damage extent in the truss structure.
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Studies on the performance of a GaInP/GaAs tandem solar cell at elevated temperatures
Статья научная
In this paper theoretical studies have been performed on a multijunction GaInP/GaAs based tandem solar cell. The top GaInP cell and the bottom GaAs cell were investigated separately. At an operating temperature of 300K, the current matching condition is fulfilled when the top cell and bottom cell base doping concentration and thickness are set to 5x1015/cm3, 1µm, and 2x1017/cm3, 0.127µm respectively. For the purpose of the investigation, a wide operating temperature range was chosen from 25ºC to 100ºC. The optimized tandem solar cell structure having a thickness of 1.847 microns is found to have VOC=2.2996V, ISC=0.0136Amp/cm2, FF=87.61% and ɳ=27.4% under AM1.5G one sun illumination. Studies have also revealed that when the cells are analyzed separately the current mismatch is less significant at low temperatures with the difference becoming notable at higher temperatures. Simulations of the solar cell were performed using PC1D.
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Study of Image Enhancement Techniques in Image Processing: A Review
Статья научная
Image denoising plays extremely important role in digital image processing. The primary objective of this paper is to explore highlighted challenges of the image filtering techniques. The comprehensive study has evidently shown that the one of most challenging issue in image filtering is edge preserving while removing the noise. Because edges deliver the most important information to the human visual system. This paper has compared different recent image filtering methods based upon certain factors. The comparisons have shown that the noise reduction using wavelet coefficients based on OMP has quite effective improvements over available methods. Challenging issue in image filtering technique is removing the multiplicative noise and high density of noises is still found.
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Study of PET Fiber Concrete in Beam-Column Joint under Cyclic Loading Using Finite Element Analysis
Статья научная
The failure behavior of beam-to-column connections can be minimized or avoided to some extent by using PET waste fibers. With the change of composition, different seismic performances of concrete joints can be adjusted. FEM analysis was performed in ABAQUS software to compare the performance of concrete beam-to-column connections reinforced with conventional concrete fibers and waste PET under cyclic loading. The concrete mix is designed to achieve a concrete grade of M25. Seven figures of the external beam-to-column connections were modeled as a quarter of the architectural prototype. The first joint is conventional concrete and designed according to IS 1893 (Part 1):2022 and the reinforcement in the joint part are specified according to the ductility requirements of IS 13920:2016. Six other samples were designed to contain different PET waste fibers (0.25% to 1.50%) in the seam area. Beam-to-column connections have 0.75% to 1.25% PET fiber inclusions that have better performance in terms of strength, load-carrying capacity, energy dissipation capacity, joint shear strength, and ductility in the joint area. Incorporating PET waste fibers into concrete can provide the best solution for waste management, and also has the potential to reduce the cost of reinforced concrete by 15%-20% holds economic significance, and concrete with PET waste fibers indeed demonstrates better seismic performance, and could lead to increased safety and longevity of structures in seismic-prone areas. This suggests that experimental work or studies might have explored how these fibers affect the concrete's properties, strength, durability, and other characteristics.
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Study on Calculation Method of Economic Velocity of Gas Phase Ethane Conveying Pipeline
Статья научная
Ethane is different from natural gas, crude oil, etc., its critical temperature is low, and it is easy to change phase with the change of ambient temperature. Therefore, it is necessary to increase the constraint condition to ensure that ethane is in the gas phase. Therefore, based on the optimization principle, the calculation model of the economical flow rate of the ethane transport pipeline including the ethane phase, the pipeline stability, and the compressor pressure ratio constraint is established with the lowest annual cost of the gas phase ethane pipeline. Solve the problem with the lowest cost. The gas-phase ethane transmission pipeline proposed in Tarim Oilfield is analyzed as an example. The results show that the economical flow rate of the pipeline under different working conditions ranges from 3 to 7 m/s, which guides the selection of the diameter of the Tarimethane pipeline. The economic design, safe operation and management of the ethane pipeline provide the basis.
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Study on Contact Fatigue Life Prediction for Clasp Joint Structure of Mooring Buoy
Статья научная
This paper focuses on predicting the contact fatigue life of the mooring buoy clasp joint structure by using the finite element program ANSYS/Fatigue. Mises equivalent stress is choosed as a stress-related fatigue criterion. An evaluation method of fatigue life under the pressure of buoyancy and wave force is established for the mooring buoy clasp joint structure. Firstly, wave force is treated as Morison dynamic force here and mooring buoys vibration model is conducted to analyze the dynamic response characteristics of vertical vibration of the mooring buoy. Secondly, dynamic contact stress calculations are conducted by directly exerting calculated vibration loads on the mooring buoy, and the stress spectrums of nodes are obtained. Finally, the S-N material fatigue curve and the Miner linear cumulative damnification principle are commonly applied to evaluate the contact fatigue life of the mooring buoy. The results show that the finite element program ANSYS/Fatigue can solve the contact fatigue problem simply, economically and efficiently. It also provides an effective engineering analysis method for these kinds of fatigue problems of the underwater mooring buoy.
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Study on the Application of Artificial Immunity in Virus Detection System
Статья научная
Artificial immunity, as a new technology, has been applied widely in virus detection system for its advantages. This paper emphasizes on these works as follows. Firstly, we analyze the disadvantages of traditional virus detection methods and new functions of artificial immune technology, and then review some typical algorithms of the existing virus detection system based on artificial immunity. Finally, a universal evaluating scheme is proposed. The purpose for this paper is to study the existent artificial immune methods and promote the new schemes emergence for virus detection system effectively.
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Статья научная
This research proposes an additional controller for load frequency control at a micro hydro power plant using PID-SMES. The PID-SMES parameters are optimized using smart methods, Imperialist Competitive Algorithms (ICA), which can find the optimal value of PID-SMES. From the analysis results, obtained on the P controller, overshoot of -0.0002176, with PI Controller -0.0002167, with PD Controller -0.0002128, with PID controller -0.0002118, with SMES controller -0.0001951, and with PID-SMES -4.11e-05. ICA optimization results obtained fitness function value of 1.79846040002633e-08, with 40 iterations. The minimum value of the system performance function at each iteration is plotted on the convergence graph shown. In the Figure it can be seen that the ICA algorithm can quickly converge on the 14th iteration or find the most optimal value at the 7th iteration. The PID-SMES controller proposed in this study has a significant influence in the damping of the oscillations. Therefore, it is proposed to be applied to micro-hydro.
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Supplier Selection through Application of DEA
Статья научная
In the increasing competition it has become important in business world to understand the different aspects of production and purchasing to understand the need for desired material in the organization. The managers have an important responsibility of selecting a good supplier by evaluating them on different parameters which is directly or indirectly associated with their overall performance. For decision making based on multiple criteria evaluation many methods of Multi-Criteria Decision Making (MCDM) is used by firms. Data Envelopment Analysis (DEA) is prominently used by firms nowadays. In this paper, analysis of DEA is done by measuring supplier performance of two firms: multi-national telecommunication corporation and a manufacturing firm. The firm uses the methodology according to their requirement and criteria for evaluating their suppliers and find best among them.
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Supply Voltage Compensation of Hot Wire Flow Measurement Device
Статья научная
Supply voltage compensation is important to keep the accuracy for hot wire/hot film gas flow sensors. A compensation experiment device is established, the two steps curve fitting is presented to determine the functional relations among flow、sensor output and supply voltage, the coefficient of fitting polynomial is determined by Least Square method, thus eliminating the influence of supply voltage variations. After compensation, the error is reduced to 2%. The algorithm is stabilized, easily to be fullfilled in microcontroller unit.
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Survey on Word Sense Disambiguation: An Initiative towards an Indo-Aryan Language
Статья научная
Resolution of lexical ambiguity, commonly known as Word Sense Disambiguation (WSD) task is to distinguish the correct sense among the set of senses for an ambiguous term depending on the particular context automatically. It plays the vital role as it acts as an intermediate phase to many Natural Language Processing (NLP) applications like Machine Translation, Information Retrieval, Speech Processing, Hypertext navigation, Parts-of -Speech tagging. Existing literature reveals that there are various approaches for lexical ambiguity resolution-Knowledge based, Corpus based. In recent years, many WSD systems is being developed in Indian languages like Hindi, Malayalam, Manipuri, Nepali, Kannada but no such automated system has yet emerged for the Indo-Aryan language- Assamese. Our future work aims to develop a model for the WSD problem which is fast, optimal and efficient in terms of accuracy and scalability. This paper presents a survey report made in this research topic discussing the WSD problem, various approaches along with their algorithms. Moreover it also list out the various NLP applications which would be efficient when disambiguation system is merged. Evaluation measures used to determine the WSD performance are also discussed here.
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Synthesis and Characterization of Ni Doped ZnO Nanoparticles
Статья научная
This paper discerns key ideas and themes of the possibility of growing Ni doped ZnO nanoparticles by electrochemical method. The purpose is to study the growth mechanism and to optimize the parameters of this method. Upon successful synthesizing the samples, they were characterized using various techniques. XRD, SEM, FTIR, photoluminescence spectroscopy together with the measured optical parameters obtained from UV-VIS absorption testing were analyzed. The X-ray diffraction (XRD) was measured by using a Bruker D8 Advance X-ray diffractometer with CuKα radiation. The surface morphology was investigated using an ‘EVO LS 15’ scanning electron microscope. The FTIR absorption spectra were recorded on a Perkin-Elmer GX FTIR system. The PL spectra were collected on a Jobin Yvon-Horiba Triax 190 spectrometer with a spectral resolution of 0.3 nm. UV-VIS absorption spectrum was recorded by using a UV-VIS spectrophotometer in the photon wavelength range between 300 and 600 nm. XRD pattern reveals that the polycrystalline of hexagonal wurtzite structure and the average size of the particles were estimated to be approximately 61 nm, which conform the nanoparticle. The FTIR result shows the stretching vibration of the Zn-O bond in Ni doped ZnO nanoparticles. There is a green emission peak centered at about 384 nm in the PL behavior. The band edge is shifted to the lower energy side of the Ni doped ZnO nanoparticle. Analyzing the results of various types of characterizations, it has been assessed that Ni doped ZnO nanoparticles was successfully synthesized.
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Technical Improvement of Air Pollution Through Fossil Power Plant Waste Management
Статья научная
Fly ash was generally released into the atmosphere in the past, but standards for air pollution control now require that it be captured before release by fitting pollution control equipment. During this process, there are many wastes for example ash and fly ash which is a waste. It is invisible, it has a nasty, and sharp smell. It affects human health when it is breathed in. It irritates the airways to cause coughing and shortness of breath. About 99% of the ash and fly ash in the air comes from human sources. The objective of this study is to reduce wastes and manage it. This project shows two different ways of waste management for two different locations which are Lukut, Malaysia, and Hanau, Germany. Both systems have advantages and disadvantages. The ash pond offers cheap costs and an easy process but exposes the fly ash and its sometimes-hazardous components to the environment. The electrostatic filter acquires more knowledge and is higher in Installation costs, but keeps fly ashes safe in a closed process the electrostatic filter seems to be more environmentally friendly and sustainable. The finding shows that this treatment was successful in reducing the wastes and managing it.
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Testing Coefficients of Autoregressive Conditional Heteroskedasticity Models by Graphical Approach
Статья научная
The graphical approach is applied to the autoregressive conditional heteroskedasticity time series models. After transformation, it is shown that the coefficients of GARCH model are the conditional correlation coefficients conditioned on the other components of the time series, then a new method is proposed to test the significance of the coefficients of GARCH model.
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Textural analysis based classification of digital X-ray images for dental caries diagnosis
Статья научная
In this paper, we propose a suitable textural feature for diagnosis of dental caries in digital radiographs. The dental diagnosis system consists of Laplacian filter for image sharpening, adaptive threshold and morphological operations for segmentation, and support vector machine (SVM) as a classifier. In segmented image, textural features are extracted, and applied to the classifier, to classify the image as caries or normal. Experimental results indicate that GLCM (Grey Level Co-occurrence Matrix) and GLDM (Grey Level Difference Method) textural features are giving better performance measures as compared to other types of textural features with an accuracy of 96.88%, sensitivity of 1, specificity of 0.8667 and precision of 96.08%. The data were analyzed by Analysis of Variance (ANOVA), at a significant level of 5%. This result indicates that the interaction of feature extraction methods on performance measures are significant. Hence, GLCM or GLDM features provide reliable decision support for dental caries diagnosis.
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Texture based Anisotropic Diffusion for Real Ultrasound Image Despeckling
Статья научная
This paper presents a new texture based anisotropic diffusion method for real ultrasound image despeckling. Texture information is obtained by a real ultrasound image model. Unlike traditional anisotropic diffusion methods usually taking image gradient as a diffusion index, we take the image texture as a new diffusion index. The results comparing our new method with others on both simulated image and real ultrasound images are reported, and our method shows the superiority in keeping important features of real ultrasound images.
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