bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of the Residual Stress Distribution in the 3D-Stacked Electronic Modules by Embedded Strain Sensors
Authors: Mizuno Ryota , Nakauchi Genta , Suzuki Ken , Miura Hideo 
Published: January 2020

Abstract
In this study, micro-scale strain sensors were embedded in a silicon chip to measure the variation of the local stress distribution around thin film interconnections used for 3D semiconductor modules. Piezoresistive effect of single crystal silicon was applied to the sensors. The stress sensitivity at room temperature was 1.3 MPa/Ω. Even though the stress sensitivity varied as a strong function of temperature, it was confirmed that this sensor can measure the stress distribution quantitatively in the temperature range from room temperature to 80°C at most. And the variation of the residual stress in electroplated copper thin films during heat treatment was investigated from the viewpoint of the change of stress amplitude during a thermal cycle. From the obtained results, it was confirmed that the recrystallization occurred when the films were annealed at only 200°C, and the change of the micro textue of the films caused the change of their residual stress. Therefore, it is very important to control the micro texture during electroplating for assuring long term reliability of interconnections.
Effect of Coating Process Parameters on the Development of Residual Stresses in Ceramic Coatings
Authors: Gadelmoula Ali , Al-Athel Khaled 
Published: January 2020

Abstract
Ceramic coatings are widely used in many engineering applications, especially applications related to components operating at elevated temperatures. One of the main issues relates to ceramic coatings is the development of residual stresses due to quenching and the thermal mismatch between the deposited coating layers and the substrate. In this work, a computational framework is developed to investigate the effect of various process parameters on the development of the residual stresses. The geometry of the coating layers and the interface roughness between the layers is first generated using SimCoat, a Monte Carlo based statistical algorithm that determines the effect of process parameters (droplet size, spraying speed, etc.) on the characteristics of the developed coating (coating thickness, porosity, etc.). An in-house code is used to convert the statistical data into a finite element (FE) model. Various FE models are generated with different process parameters, and the development of residual stresses is compared between them. The developed framework can be used by material scientists and engineers to predict the quality of the coating and optimize the process parameters to any specific application.
Neural Network Inverse Based Omnidirectional Rotation Decoupling Control to the Electrodynamic Reaction Sphere
Authors: Huai Zhouyu , Zhang Ming , Zhu Yu , Chen Anlin , Li Xin , Wang Leijie 
Published: January 2020

Abstract
The electrodynamic reaction sphere is a novel actuator for the spacecraft attitude control subsystem. This paper proposes a neural network inverse based decoupling control scheme to actualize the omnidirectional rotation of the electrodynamic reaction sphere which has strong multivariable nonlinear coupling features due to the induction-based drive. And an integrated electromagnetic torque model of the reaction sphere is firstly derived from the electromagnetic field analysis and modified with the finite element analysis method. Then based on the integrated torque model, a back propagation feedforward neural network is constructed and trained to approach the inverse dynamics which transforms the original system into a pseudo-linear system. Furthermore, an additional PI controller is introduced to achieve good control performance against the unmodelled dynamics. Finally, the effectiveness of the proposed method is validated by simulations.
A Computer Vision Based Automated Polarity Testing System of Rocket Motor Nozzle
Authors: Wang Guan , Yi Hang , Zhou Dengji 
Published: January 2020

Abstract
Launch vehicle realizes pitch, yaw and roll control through the swing of motor nozzles. Current rocket motor polarity test relies on simultaneous close observation of multiple nozzles by trained testers which thereby is both time-consuming and low-automation. And it is difficult for the human eye to recognize and track the working condition with a small amount of fast swing. By installing a set of cameras and designing a measurement system based on computer vision method, the oscillation trajectory and polarity of each nozzle can be effectively judged. We show that our system is able to improve test efficiency as well as test coverage, make testing process traceable and ensure measurement reliability.
Design of Metallic Support for Electronic Devices Installed on the Interstage 2/3 of Vega-C Launcher
Authors: Di Caprio F. , Cristillo D. , Giusto G. , Zallo A. 
Published: January 2020

Abstract
The purpose of this paper is to provide a numerical procedure developed to obtain the best design (in terms of weight and requirement fulfillment) for a structural component subjected to a launcher environment. The component analyzed represents the support used to mount the SAD/S and DBAT equipment into the VEGA C launcher Interstage 2/3. The final design is obtained by means of an optimization process which aims to satisfy the environmental requirements prescribed by the Vega General Specifications. The developed procedure is based on generation of a fully parametric FE model that is able to switch between ANSYS and NASTRAN software. This routine allows us to execute a topometry optimization with Nastran (by using a 2D model) and to generate a full 3D model (which represents the best compromise among structural performance, manufacturing cost and weight) with Ansys. The final design shows a weight reduction about 50% with respect to the initial provided model.
An Optimized 3D Probe Using Sensitivity and Compliance Analysis
Authors: Zheng Weikang , Liu Zhigang , Guo Junkang 
Published: January 2020

Abstract
High-precision micro/nano probe plays an increasingly important role in manufacturing and measurement. The multi-arm elastic mechanism that can produce deformation under the contact force is widely used in the design of probe. The striking feature of this mechanism is that multiple variables are coupled to each other and are not easily separated. However, the transfer matrix of probe, rather than a multivariable decoupling model, is widely used as a measurement model in traditional research. Transfer matrix appears as a “black box” and does not reveal working principles of probe. Our previous research proposed a 3D decoupling model. The 3D model presents the coupling relationship between input and output variables, and also finishes a theoretical explanation of complex features of 3D probe. Recent studies have found that this decoupling model has practical value in parameter and shape optimization of probe. As the optimized purpose, two indicators — sensitivity and compliance (reciprocal of stiffness) are proposed from the model. The increased sensitivity means the probe has a lower resolution requirement for the capacitive sensor used. High compliance of probe means small contact force between the stylus ball and workpiece. Excessive stiffness can cause excessive contact forces that damages surface of workpiece. Combined with theoretical model and finite element analysis (FEA), the key parameters affecting sensitivity and compliance of probe are extracted, and a new optimized elastic mechanism based on an original Hexflex mechanism. The new optimized probe has better performance with sensitivity, input compliance, output compliance increased by 78.6%, 48.4%, 157.7%, respectively.
Telemetry Data Prediction of Launch Vehicle Attitude Control Engine Using LSTM
Authors: Yi Hang , Wang Guan , Geng Hui , Xu Hao , Wang Wei , Zhou Dengji 
Published: January 2020

Abstract
The attitude control engine used by the launch vehicle is mainly composed of a pressurized gas cylinder, a pressure reducer, a tank, a duct, a pitch extension, a roll extension, a yaw extension, and a sinker extension. In this paper, a long short-term memory network is used to train the telemetry data transmitted from the temperature and pressure sensor points distributed in various positions of the attitude control engine, such that the state of the rocket attitude control engine can be deduced and predicted in real time through the data-driven digital twinning system. It is possible to detect potential data anomalies in advance and locate the faults, so that the control system can change the attitude control strategy in sufficient time to alleviate the fuel loss issue as well as positional deviation caused by minor faults, so as to better ensure the success of the mission.
Influence of Precipitation and Dislocation Density on Flow Stress Characteristics Under Compression Deformation of Heat-Treated 17-4 PH Stainless Steel Alloy
Authors: Sathyanath Athul , Meena Anil 
Published: January 2020

Abstract
The strengthening mechanism of 17-4 PH stainless steel is mainly due to the precipitation of copper particles in the martensitic lath matrix. The renowned steel grade possesses an exceptional combination of high strength and excellent corrosion resistance and hence is widely employed in high stress environments. In that case, under external loading, the movement and accumulation of dislocations are influenced by the nature of precipitation. Hence, the present study is based on the impact of precipitation on the dislocation induced hardening during compression of the heat-treated 17-4 PH stainless steel. Room temperature uniaxial compression test was used to evaluate the direct effect of precipitates and the dislocation interaction on the flow stress and strain-hardening behavior under the different heat-treated regime. Microstructural evolution during deformation and its influence on the strain-hardening mechanism were analyzed by optical microscopy (OM), scanning electron microscopy (SEM) and X-ray diffraction (XRD). A semi-empirical model was adopted to quantify the role of precipitate nature on the strain-hardening rate. The evaluated normalized microstrain and dislocation density from the XRD analyses were used to explain the observed variation in the mechanical property. Coarse particle precipitation was found to greatly affect the strain-hardening behavior of the steel alloy during compression deformation.
Weld Bead Performance Assessment of P-GMAW Using Acoustic Emission (AE) Signals Through NDT Methods for MS ASTM A 106 B Grade Material
Authors: Addamani Rudreshi , Venkatadasu Ravindra Holalu 
Published: January 2020

Abstract
Pulsed Gas Metal Arc Welding (P-GMAW) process is used in many industries to gain high quality, productivity and cost effective products in fabrication of welded joints. The input process parameters will affect the quality, productivity and cost of the welding and are considered to be the most important factors. P-GMAW is an excellent alternative to constant voltage GMAW process for those industries which are looking to boost efficiencies since the process helps to improve quality of welds over varying operator’s skills. The process enables low mean current and low net heat input with stable spray transfer. To produce a very precise control of the arc, P-GMAW applies waveform control logic through a broad wire feed and speed range. In order to understand and control the P-GMAW welding process, it is necessary to determine the input and output relationship parameters. The process is modified spray transfer in which the power source switches between low background current or voltage and a high peak current or voltage between 30 to 400 times per second. Over this period, the peak current pinches off droplets of wire and drive it to the welded joints. By the mean time, background current maintains the arc but produces low heat input that metal transfer cannot occur allowing weld pool to solidify. The process enables low mean current and low net heat input with stable spray transfer. The objective of the present study is to assess the weld bead performance and joint strength by carrying out the destructive testing using AE signals. Experiments have been conducted on MS ASTM A 106 material using 1.2 mm copper coated filler wire based on the Taguchi’s L27 standard orthogonal array. Input parameters considered to carry out the experiments are current, gas flow rate and wire feed rate with a constant speed. The direct response parameters are Ultimate Tensile Strength (UTS, N/mm2), Yield strength (YS, N/mm2) and % of elongation. Indirect response parameters signals are Viz., Acoustic Emission (AE) signals such as welding AERMS, welding AEENERGY, tensile AERMS and tensile AEENERGY are considered to assess the performance of the weld bead joint. From the obtained results, it is clearly observed that a good relationship exists between welding AERMS welding AEENERGY with tensile AERMS and tensile AEENERGY to evaluate the performance of the weld bead joint. The results are validated through carrying out different NDT testing methods on weld bead joint Viz., macro test examination, X–radiography, scanning electron microscope images to analyse external and internal defects in the welded joints. EDX investigation is performed for elemental composition on welded joint in different zones.
Heat Transfer Characteristics of a Train of Droplets Impinging Over a Hot Surface: From Film Evaporation to Leidenfrost Point
Authors: Guggilla Ganesh , Pattamatta Arvind , Narayanaswamy Ramesh 
Published: January 2020

Abstract
Due to the advancements in computing services such as machine learning and artificial intelligence, high-performance computing systems are needed. Consequently, the increase in electron chip density results in high heat fluxes and required sufficient thermal management to maintain the servers. In recent times, the liquid cooling techniques become prominent over air cooling as it has significant advantages. Spray cooling is one such efficient cooling process which can be implemented in electronics cooling. To enhance the knowledge of the process, detailed studies of fundamental mechanisms involved in spray cooling such as single droplet and multiple droplet interactions are required. The present work focuses on the study of a train of droplets impinging over a heated surface using FC-72 liquid. The surface temperature is chosen as a parameter, and the Dynamic Leidenfrost point (DLP) for the present impact conditions is identified. Spread hydrodynamics and heat transfer characteristics of these consecutively impinging droplets till the Leidenfrost temperature, are studied and compared.
Design Process Deconstructed: The Industry Case of an Elevator Button Assembly Redesigned for Additive Manufacturing
Authors: Puttonen Tuomas 
Published: January 2020

Abstract
Additive manufacturing (AM) has during the 21st century gradually shifted from prototyping towards the manufacture of end-use quality parts. The drivers to utilize AM instead of conventional manufacturing methods are often linked to geometrical design freedom, increased performance, customization, part consolidation, and weight reduction. However, designers have struggled to take full advantage of these new capabilities. In part, this is due to a pervasive engineering mindset locked into the constraints of conventional manufacturing technologies. Another reason is the lack of efficient design methodologies that would take into account the new capabilities of AM.
In this paper, to address the latter deficiency, an assembly redesign process for AM is deconstructed and analyzed. The studied assembly is an elevator accessibility button, which is a high-mix low-volume product. From the industry perspective, AM could reduce costs and increase the agility of production. Through systematic requirements mapping, part- and product-level functional analysis, a holistic functional analysis of the product is composed. The results of the product functional analysis are illustrated in a visual 3D design space. The 3D illustration is suggested as a conceptualization tool for the designers and as a way to reinforce creativity in the design process. The usability and expandability of the tool are discussed and contrasted with the current design methodologies for AM.
Decontamination of Heavy Metals From Municipal Sewage Sludge (MSS) by Electrokinetic Remediation
Authors: Ribeiro A. , Araújo J. , Mota A. , Campos R. , Vilarinho C. , Carvalho J. 
Published: January 2020

Abstract
A large quantity of sludges resulting from the treatment of MWWTP (Municipal Wastewater Treatment Plant) effluent is generated annually following the increase of population density and acceleration of urbanization. Sludge production in Europe has been predicted by around 12 million tons in 2020. As a solid waste, appropriate disposal of Municipal Sewage Sludge (MSS) has been taken seriously due to its larger volume and toxic substances such as heavy metals.
Electrokinetic remediation has more advantages in heavy metals uptake compared to other technologies, due to the ability to treat soils in-situ and to remove heavy metals from soils. In this work, it was studied the remediation of MSS by the electrokinetic remediation coupled with activated carbon (AC) as a permeable reactive barrier (PRB). It was applied an electric current of 3 V cm−1 and it was used an AC/sludge ratio of 30 g kg−1 of contaminated sludge for the preparation of the PRB. In each trial, the evolution of cadmium (Cd), lead (Pb), copper (Cu), chromium (Cr), nickel (Ni) and zinc (Zn) removal from the sludge were evaluated.
Results proved that this process is perfectly suited for the removal of chromium, nickel and zinc metals from the sludge. At the end of the operation time, it was achieved a maximum removal rate of 56% for chromium, 73% for nickel and 99% for zinc, with initial concentrations of 2790 mg kg−1, 2840 mg kg−1, and 94200 mg kg−1, respectively.
Based on these results, it was proved the technical viability of the proposed technology (electrokinetic with AC as a permeable reactive barrier) to treat municipal sewage sludges.
A Knowledge-Based Engineering Workbench for Automated Tolerance Specification
Authors: Sauer Christopher , Heling Bjoern , Schmutzler Simon , Schleich Benjamin 
Published: January 2020

Abstract
Designers often lack important information about achievable manufacturing tolerances. Moreover tolerances are not considered from the beginning of product development. This often leads to inaccurately specified parts. Furthermore the full potential of the manufacturing departements is not used.
This contribution tackles those areas by presenting a knowledge-based engineering workbench for automated tolerance specification, which has also been implemented using a commercial CAD system. This tool allows the designer to assign part tolerances that take into account the achievable accuracies for a specific manufacturing process, while at the same time allowing for specific part properties. The novelty of the presented approach can be found in the knowledge-based support of the product developers in tolerance specification by employing an engineering workbench. Moreover preprocessing for variation simulation and analysis is supported. It is possible to automate parts of the tolerance specification process, using the presented approach.
Simulation Model Uncertainty Quantification and Model Calibration for Natural Gas Compressor Units
Authors: Wei Tingting , Zhou Dengji , Yao Qinbo , Zhang Huisheng , Lu Zhenhua 
Published: January 2020

Abstract
Natural gas compressor units, as the core equipment in natural gas transportations, play a crucial role in daily industrial production. Meanwhile, with the increase of equipment operating time, the performance of each component will inevitably decline and even fail in severe cases. Apparently, the unit simulation model, also known as the mechanism model with the characteristic maps, lays foundation for remotely monitoring the conditions of this rotating machine and giving the suggestions for equipment maintenance. And it should be accurate and adaptive according to the performance degradation. To achieve this goal, some thermodynamic parameters and their data samples are decided to represent this model with the Grey Relational Analysis and the optimal Latin Hypercube Sampling. Then, a data-driven model based on Gaussian process is established and the Bayesian calibration method is applied to obtain the model uncertainty, which means the degradation uncertainty in this study. This approach can realize the uncertainty quantification and the result can be adopted to judge and correct the characteristic map in the simulation model. A case study is implemented on an industrial compressor unit to demonstrate this method’s effectiveness. The corrected model outputs are compared with the actual data to acquire the model accuracy and their variance is 0.993, which points out their similarities. This approach avoids the disadvantages of the traditional model correction methods such as low utilization rate of operational data, non-use of prior information, and long fitting time. It makes full use of prior information and numerous data. Besides, it can reduce the diagnostic error, provide new possibility for the real-time monitor and promote the development of health management in the industrial equipment.
Numerical Determination of Unconstrained Area Effect on Springback in Incremental Forming of 5052-H32 Aluminum
Authors: Grimm Tyler J. , Mears Laine 
Published: January 2020

Abstract
Incremental forming (IF) is a novel sheet material forming process which promises significant energy savings within the low and medium volume sheet production industries. This advantage stems from IF’s dieless forming nature, which alleviates the need for time and energy input towards die fabrication and offers significantly greater flexibility. However, a distinct disadvantage of this process is its relatively low forming rate compared to conventional stamping, which reduces its feasibility of use in higher volume productions.
Springback is one disadvantage of incremental forming which has hindered its implementation within industry. Spring-back reduction methods, as well as springback characterization, can be found throughout literature. However, very few publications disclose the clamping dimensions used for fixturing work-pieces. This study numerically determines the springback effect of utilizing various clamping structures and presents an empirical solution for determining the springback of truncated pyramid geometries for various constraining areas. The resulting equation was found to have an acceptable degree of error relative to experimental analysis.