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Nowadays, the use of forged e-passport is increasing, which is threatening national security. It is important to improve the national security against international crime or terrorism. There is a weak verification process caused by lack of identification processes such as a physical check, biometric check and electronic check. The e-passport can prevent the passport cloning or forging resulting from the illegal immigration. The paper aims to discuss these issues.

This paper focuses on face recognition to improve the biometric authentication for an e-passport, and it also introduces facial permanent mark detection from the makeup or cosmetic-applied faces, twins and similar faces. An algorithm is proposed to detect the cosmetic-applied facial permanent marks such as mole, freckle, birthmark and pockmark. Active Shape Model into Active Appearance Model using Principal Component Analysis is applied to detect the facial landmarks. Facial permanent marks are detected by applying the Canny edge detector and Gradient Field Histogram of Oriented Gradient.

This paper demonstrated an algorithm and proposed facial marks detection from cosmetic or makeup-applied faces for a secure biometric passport in the field of personal identification for national security. It also presented to detect and identify identical twins and similar faces. This paper presented facial marks detection from the cosmetic-applied face, which can be mixed with traditional methods. However, the use of the proposed technique faced some challenges due to the use of cosmetic. The combinations of the algorithm for facial mark recognition matching with classical methods were able to attain lower errors in this proposed experiment.

The proposed method will enhance the national security and it will improve the biometric authentication for the e-passport. The proposed algorithm is capable of identifying facial marks from cosmetic-applied faces accurately, with less false positives. The proposed technique shows the best results.

The purpose of this paper is to establish a paint deposition pattern model applied to robotic air spray painting in order to achieve the accuracy and uniformity of paint film thickness on free‐form surface.

The paper opts for an exploratory study using the curvature circle method for air spray painting on free‐form surface to construct a spray gun model. First, a paint deposition pattern model of ellipse dual‐β distribution is fitted on the basic of experimental data from robotic air spray painting. Second, a spray gun model is proposed using the curvature circle method for air spray painting on free‐form surface. The theoretical result is coincident with the film thickness in verification experiment spraying a cylinder surface. The biggest error of the sample points between the theoretical and experimental results is less than 4 μm, thereby the correctness and effectiveness of the proposed model is validated.

The paper provides a specific theoretical and methodological support for the realization of process planning and simulation system in surface spray manufacturing. It will make the future developed system meet the actual processing requirement. At the same time, it is more representative.

The paper finds an approach to solve paint deposition pattern model suitable to free‐form surface. The present method can be applied to the complex reality of topological relation for actual workpiece surface to be painted.

This research investigated the mechanism of wet friction plates of engagement and solved the problem that the lock-up friction coefficient of sinter material could not be obtained but from experiments for a long time. The paper aims to discuss these issues.

Including four steps: surface topology sampling and reconstruction, fractal parameters obtaining and fractal surface simulating, micro-contact mechanics model and friction coefficient fractal model, and experimental verification.

After running in stage of the friction plates, the fractal dimension would reach a dynamically stable stage for a long time. The proportional coefficient K expresses the correlation between the base hardness and the asperities shear strength. The model could be property for one or more working condition via adjusting the coefficient K. The experiment data of friction coefficient are increased as the load magnified both in the model prediction and experiment practice. The trend is different from other models.

This research is original and it is supported by national defense project. It would be served for tracked vehicles to solve the defect in transmission system. The friction coefficient is obtained via solving the tangential force in MB model. The surface topography could be reconstructed by laser topography instrument and the parameters could be received by program.

For the robot-assisted upper limb rehabilitation training process of the elderly with damaged neuromuscular channels and hemiplegic patients, bioelectric signals are added to transform the traditional passive training mode into the active training mode.

This paper mainly builds a steady-state visual stimulation interface, an electroencephalography (EEG) signal processing platform and an exoskeleton robot verification platform. The target flashing stimulation blocks provide visual stimulation at the specified position according to the specified frequency and stimulate EEG signals of different frequency bands. The EEG signal-processing platform constructed in this paper removes the noise by using Butterworth band-pass filtering and common average reference filtering on the obtained signals. Further, the features are extracted to identify the volunteer’s active movement intention through the canonical correlation analysis (CCA) method. The classification results are transmitted to the upper limb exoskeleton robot control system, combined with the position and posture of the exoskeleton robot to control the joint motion of robot.

Through a large number of experimental studies, the average accuracy of offline recognition of motion intention recognition can reach 86.1%. The control strategy with a three-instruction judgment method reduces the average execution error rate of the entire control system to 6.75%. Online experiments verify the feasibility of the steady-state visual evoked potentials (SSVEP)-based rehabilitation system.

An EEG signal analysis method based on SSVEP is integrated into the control of an upper limb exoskeleton robot, transforming the traditional passive training mode into the active training mode. The device used to record EEG is of very low cost, which has the potential to promote the rehabilitation system for further widely applications.

This paper aims to present a case study of virtual-reality-based product demonstrations featuring items of furniture. The results will be of use in further design and development of virtual-reality-based product demonstration systems and could also support effective student learning.

A new method was introduced to guide the experiment by confirming orthogonal arrays. User interactions were then planned, and a furniture demonstration system was implemented. The experiment comprised two stages. In the evaluation stage, participants were invited to experience the virtual-reality (VR)-based furniture demonstration system and complete a user experience (UX) survey. Taguchi-style robust design methods were used to design orthogonal table experiments and planning and design operation methods were used to implement an experimental display system in order to obtain optimized combinations of control factors and levels. The second stage involved a confirmatory test for the optimized combinations. A pilot questionnaire was first applied to survey demonstration scenarios that are important to customers.

The author found in terms of furniture products, product interactive display through VR can achieve good user satisfaction through quality design planning. VR can better grasp the characteristics of products than paper catalogs and website catalogs. And VR can better grasp the characteristics of products than online videos. For “interactive inspection”, “function simulation”, “style customization” and “set-out customization” were the most valuable demonstration scenarios for customers. The results of the experiment confirmed that the “overall rating”, “hedonic appeal” and “practical quality” were the three most important optimized operating methods, constituting a benchmark of user satisfaction.

The author found that it is possible to design and build a VR-based furniture demonstration system with a good level of usability when a suitable quality design method is applied. The optimized user interaction indicators and implementation experience for the VR-based product demonstration presented in this study will be of use in further design and development of similar systems.

The hydrodynamic characteristics of liquid film for bearings, especially water-lubricated bearings with a large length-to-diameter ratio, affect the dynamics behavior of rotor bearing systems. The purpose of this study is to carry out theoretical analysis and experiments to determine the hydrodynamic characteristics of water-lubricated journal bearings.

The finite difference method is adopted for the simulation of the characteristics of water-lubricated bearings. The comparison results between water-lubricated bearings with and without grooves, as well as with and without the consideration of the effects of rubber deformation, are presented. The test bearings, test bench, and monitoring system, especially the force exciter for the bearing experiment, are presented. Dynamic coefficient identification verification experiments were performed in different working situations. The obtained results include the calibration of magnetic force, two kinds of excitation, vibration data of the rotor system and dynamic coefficients.

The theoretical results demonstrate that the hydrodynamic effect was obvious when the speed was increased and that the water film had improved capability at a working speed of 1800 rpm. The identification results reveal the lubrication situation of the test bearing under low-speed and high-load conditions. Moreover, it was found that the liquid film was not continuous at low speeds.

The theoretical results can lead to the enhancement of the design level of water-lubricated rubber journal bearings with a large aspect ratio. The experimental results can lead to the improvement of the dynamic behavior design of rotor systems supported using water-lubricated bearings with a large length-to-diameter ratio.

This paper aims to present a new friction-stir-weld robot for large-scale complex surface structures, which has high stiffness and good flexibility.

The robot system is designed according to manufacturability of large aluminum products in aeronautic and astronautic area. The kinematic model of the robot is established, and a welding trajectory planning method is also developed and verified by experiments.

Experimental results show that the robot system can meet the requirements of friction stir welding (FSW) for large-scale complex surface structures.

Compared with other heavy robotic arm and machine tool welding devices, this robot has better working quality and capability, which can greatly improve the manufacturability for large-scale complex surface structures.

The friction-stir-weld robot system is a novel solution for welding large-scale complex surface structures. Its major advantages are the high stiffness, good flexibility and high precision of the robot body, which can meet the requirements of FSW. Besides, a welding trajectory planning method based on iterative closest point (ICP) algorithm is used for welding trajectory.

The purpose of this paper is to analyze the case of a manufacturing firm situated in an industrial city of India, focusing on supply chain management issues of the concerned organization from two operational perspectives: supply side (or the procurement side) and the distribution side of the system.

The authors first considered the outsourcing decision‐making problem in a static environment using analytical expression by means of a variable fraction of demand. Next, the authors extended the scope of this problem by considering outsourcing decisions in a dynamic environment, using the sequential decision‐making approach with various operational and inventory factors. Finally, the authors carried out the study of the distribution side of the supply chain of industry using discrete event simulation.

It was observed that, in the case study organization, because of the rather unstructured approach in dealing with the outsourcing perspective, the authors suggested the adoption of a more scientific approach in computation of fraction of demand to be outsourced. Further, since the distribution network typically experienced high inventory levels throughout the supply chain, it was decided upfront to optimize this performance measure.

The primary objectives of this exercise are to: address the operational concerns of a real‐life manufacturing environment; apply the theoretical models in a realistic environment, and compare the results of theory with practice; and provide actionable managerial recommendations.

This study aims to focus on the effect of interlayer bonding and thermal decomposition on the mechanical properties of fused filament fabrication-printed polylactic acid specimens at high extrusion temperatures.

A printing process, that is simultaneous manufacturing of contour and specimen, is used to improve the printing accuracy at high extrusion temperatures. The effects of the extrusion temperature on the mechanical properties of the interlayer and intra-layer are evaluated via tensile experiments. In addition, the microstructure evolution affected by the extrusion temperature is observed using scanning electron microscopy.

The results show that the extrusion temperature can effectively improve the interlayer bonding property; however, the mechanical properties of the specimen for extrusion temperatures higher than 270°C may worsen owing to the thermal decomposition of the polylactic acid (PLA) material. The optimum extrusion temperature of PLA material in the three-dimensional (3D) printing process is recommended to be 250–270°C.

A temperature-compensated constitutive model for 3D printed PLA material under different extrusion temperatures is proposed. The present work facilitates the prediction of the mechanical properties of specimens at an extrusion temperature for different printing temperatures and different layers.

This paper discusses the optimization of the process parameters for the hybrid‐layered manufacturing (HLM) process during its weld layer deposition with subsequent surface machining in attaining the desired accuracy and contour profile of the deposited weld layer thickness.

The HLM process integrates the synergic metal inert gas (MIG) – metal active gas (MAG) welding process for depositing the metal layer of a desired slice thickness and perform the computer numerical control (CNC) machining process on the deposited layer to enhance both the surface quality and dimensional accuracy of the deposited layer. For the HLM process the weld bead geometry plays a vital role in determination of the layer thickness, surface quality, build time, heat input into the deposited layer and the hardness attained by the prototype. A feasible weld bead width and heights are to be formulated for the exterior contour weld path deposition and for the interior weld cladding. Thus, Taguchi methodology was employed with minimum number of trails as compared with classical statistical experiments. This study systematically reveals the complex cause‐effect relationships between design parameters and performance.

Statistical design of experiments using orthogonal arrays and signal‐to‐noise (S/N) ratios are performed to constitute the core of the robust design procedure. Experimental confirmations of the performance characteristic using the derived optimal levels of process parameters are provided to confirm the effectiveness of this approach.

The welding parameters such as current, voltage, arc length, wire feed rates, wire stick‐out distance, shielding gas, filler wire diameter, weld speed, etc. will influence on the deposited weld bead geometry. Further investigations are to be carried out during adaptive layer deposition on the induced thermal stresses and its influence on the hardness of the deposited weld layer.

This paper describes a low cost direct rapid tooling process, HLM. This unique methodology would reduce the cost and time to make molds and dies that are used in batch production.