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The use of removable complete dentures is a selectable restorative procedure for edentulous patients. To improve the fabrication quality and efficiency of removable complete dentures, this paper aims to introduce a new method to fabricate customized wax complete dentures with additive manufacturing. This process uses complementary digital technologies, and allows faster and better manufacture of complete dentures.

In the study, a dental scanner was used to obtain surface data from edentulous casts and rims made by the dentist. A parameterized three-dimensional graphic database of artificial teeth was pre-established. Specialized computer-aided design software was used to set up the artificial dentition and design the esthetic gingiva and base plate. A selective laser sintering machine was used to transfer the data from stereolithography files into a wax base plate with location holes for each artificial tooth.

Under this method, a set of wax base plates with 28 location holes available for the placement of the artificial teeth were designed and fabricated within 6 h. The try-in wax dentures fitted the patient’s mouth well, besides occlusion relationships. Then, the occlusion relationships can be adjusted manually to achieve a balanced centric occlusion.

This method can be used to design and fabricate wax try-in removable complete dentures semi-automatically and rapidly; however, the algorithm for the occlusion contact design needs to be improved.

This paper aims to introduce an imitation learning framework for a wheeled mobile manipulator based on dynamical movement primitives (DMPs). A novel mobile manipulator with the capability to learn from demonstration is introduced. Then, this study explains the whole process for a wheeled mobile manipulator to learn a demonstrated task and generalize to new situations. Two visual tracking controllers are designed for recording human demonstrations and monitoring robot operations. The study clarifies how human demonstrations can be learned and generalized to new situations by a wheel mobile manipulator.

The kinematic model of a mobile manipulator is analyzed. An RGB-D camera is applied to record the demonstration trajectories and observe robot operations. To avoid human demonstration behaviors going out of sight of the camera, a visual tracking controller is designed based on the kinematic model of the mobile manipulator. The demonstration trajectories are then represented by DMPs and learned by the mobile manipulator with corresponding models. Another tracking controller is designed based on the kinematic model of the mobile manipulator to monitor and modify the robot operations.

To verify the effectiveness of the imitation learning framework, several daily tasks are demonstrated and learned by the mobile manipulator. The results indicate that the presented approach shows good performance for a wheeled mobile manipulator to learn tasks through human demonstrations. The only thing a robot-user needs to do is to provide demonstrations, which highly facilitates the application of mobile manipulators.

The research fulfills the need for a wheeled mobile manipulator to learn tasks via demonstrations instead of manual planning. Similar approaches can be applied to mobile manipulators with different architecture.

Robotic systems for laparoscopic minimally invasive surgery (MIS) always end up with highly sophisticated mechanisms and control schemes – making it a long and hard development process with a steep price. This paper aims to propose and realize a new, efficient and convenient strategy for building effective control systems for surgical and even other complex robotic systems.

A novel method that takes advantage of the modularization concept by integrating two middleware technologies (robot operating system and robotic technology middleware) into a common architecture based on the strengths of both was designed and developed.

Tests of the developed control system showed very low time-delay between the master and slave sides; good movement representation on the slave manipulator; and high positional and operational accuracy. Moreover, the new development strategy trial came with much higher efficiency and lower costs.

This method results in a modularized and distributed control system that is amenable to collaboratively develop; convenient to modify and update; componentized and easy to extend; mutually independent among subsystems; and practicable to be running and communicating across multiple operating systems. However, experiments show that surgical training and updates of the robotic system are still required to achieve better proficiency for completing complex minimally invasive surgical operations with the proposed and developed system.

This research proposed and developed a novel modularization design method and a novel architecture for building a distributed teleoperation control system for laparoscopic MIS.

The purpose of this paper is to investigate a five-phase permanent-magnet synchronous machine (PMSM) that features high-power density and high-fault-tolerant capability for electric vehicles (EVs).

The five-phase 20-slot/18-pole PMSM is designed by finite-element method. Two typical rotor structures which include Halbach array and rotor eccentricity are compared to achieve sinusoidal back electromotive force (EMF). The influence of slot dimensions on leakage inductance and short-circuit current is analyzed. The method to reduce eddy current loss of permanent magnets (PMs) is investigated. The machine performances under both healthy and fault conditions are evaluated. Finally, thermal behavior of the machine is studied by Ansys.

With both no-load and load performances considered, rotor eccentricity is proposed to reduce the harmonic contents of EMF. Increasing slot leakage inductance is an effective way to limit the short-circuit current. By segmenting PMs in circumferential direction, the PM eddy current loss is reduced and the machine efficiency is improved. With proper fault-tolerant control strategy, acceptable torque performance can be achieved under fault conditions. The proposed machine can safely operate under Class F insulation.

So far, many researches focus on multiphase PMSMs used in aviation fields, such as fuel pump and electric actuator. Differing from PMSMs used in aviation applications, machines for EVs require characteristics like wide speed ranges and variable operating conditions. Hence, this paper proposes a five-phase 20-slot/18-pole PMSM for EVs. The proposed design methodology is applicable to multiphase PMSMs with different slot/pole combinations.

With respect to the multiple-attribute decision-making problem with subjective preference for a certain attribute whose weight-value range have been given over other attributes whose weight values are unknown, a method based on the mean value of the grey number is proposed to analyse the decision-making problem. This method is used to choose a supply-chain partner under the condition that the decision makers have a preference for a certain attribute of various alternatives. The paper aims to discuss these issues.

First, the middle value of the preferred attribute’s weight-value range is supposed to be its weight value according to the content of the mean value of the grey number. Second, to reflect the decision maker’s subjective preference information, an improved optimisation model that requests the minimum deviation between the actual and expected numerical value of each attribute is constructed to assess the attributes’ weights. Third, the correlated degree and the correlation matrix, which are determined by the weight values of all attributes, are used to rank all the alternatives.

This paper provides a method for making a decision when decision makers have a preference for a certain attribute from an array of various alternatives, and the range of the certain attribute’s weight value is given but the weight value of the other attributes is unknown. When applied to supply-chain partner selection, this method proves feasible and effective.

This method is feasible and effective when applied to supply-chain partner selection, and can be applied to other kinds of decision-making problems. This means it has significant theoretical importance and extensive practical value.

Based on the mean value of the grey number, an optimisation model is built to determine the importance degree of each attribute, then the correlated degree of each alternative is combined to rank all the alternatives. This method can suit the decision makers’ subjective preference for a certain attribute well.

This paper aims to review the latest management developments across the globe and pinpoint practical implications from cutting-edge research and case studies.

This briefing is prepared by an independent writer who adds their own impartial comments and places the articles in context.

Firms that pursue green strategies can boost performance and reputation. Adopting this approach additionally helps build and maintain relationships with other firms to generate benefits which offset costs involved in strategy development.

The briefing saves busy executives and researchers’ hours of reading time by selecting only the very best, most pertinent information and presenting it in a condensed and easy-to-digest format.

With the increasing attention acquired from researchers and practitioners in Architecture, Engineering and Construction (AEC) industry, building information modeling (BIM) has fundamentally changed the approach we design, construct and delivery, as well as operate and maintenance of buildings and civil infrastructures. This study tries to provide an innovative perspective on BIM research. This study aims to analyze the necessity and feasibility of BIM user satisfaction research and define what BIM user satisfaction is, and then to develop a quantitative method for the measurement of BIM user satisfaction.

As it is indicated in the content, BIM user satisfaction is measured by the sum of the user's weighted reactions to a set of factors. To be specific, the entropy method was adopted to calculate the “weighting” of the factors, and the triangular fuzzy number (TFN) method was selected to compute the “scoring” of the factors. Through the literature review, methodology and tool development, as well as case study and discussions, this paper was generated sequentially.

This study found that the proposed tool for the measurement of BIM success is valid and reliable; it formerly translated the conceptual definition of BIM user satisfaction into an accurate measurement instrument. It also indicated that many factors are affecting the BIM users' satisfaction, and each of the factors inherited various importance and score, and the findings are expected to improve the performance and effectiveness of BIM management.

Through the translation of the conceptual BIM user satisfaction into a valid quantitative measurement instrument, this research provides an excellent framework for the management of BIM from the user's perspective, and it could help to stimulate user's acceptance of BIM in the AEC industry in future.

An investigation was conducted into the impact of various process parameters on the surface and subsurface quality of glass-ceramic materials, as well as the mechanism of material removal and crack formation, through the use of ultrasonic-assisted grinding.

A mathematical model of crack propagation in ultrasonic-assisted grinding was established, and the mechanism of crack formation was described through the model. A series of simulations and experiments were conducted to investigate the impact of process parameters on crack depth, surface roughness, and surface topography during ultrasonic-assisted surface and axial grinding. Additionally, the mechanism of crack formation was explored.

During ultrasonic-assisted grinding, the average grinding forces are between 0.4–1.0 N, which is much smaller than that of ordinary grinding (1.0–3.5 N). In surface grinding, the maximum surface stresses between the workpiece and the tool gradually decrease with the tool speed. The surface stresses of the workpiece increase with the grinding depth, and the depth of subsurface cracks increases with the grinding depth. With the increase of the axial grinding speed, the subsurface damage depth increases. The roughness increases from 0.780um/1.433um.

A mathematical model of crack propagation in ultrasonic-assisted grinding was established, and the mechanism of crack formation was described through the model. The deformation involved in the grinding process is large, and the FEM-SPH modeling method is used to solve the problem that the results of the traditional finite element method are not convergent and the calculation efficiency is low.

The impact of network centrality on innovation performance is inconclusive. The purpose of this paper is to examine how formal and informal institutions affect the influence of network centrality on firms’ innovation performance in emerging economies by integrating social network theory and institutional theory.

Multisource and lagged data from 234 technology-based entrepreneurial firms listed on the Chinese Growth Enterprise Market were leveraged to test a proposed research model.

Results suggest that formal institutions (marketization) positively moderate the relationship between network centrality and innovation performance, whereas informal institutions (social cohesion) negatively moderate this relationship. Moreover, formal and informal institutions have a strong joint impact on such relationship, that is, the effect of network centrality on innovation performance is most positive when marketization is high and social cohesion is low.

This empirical research provides new insights into whether and how firms can grasp the innovation benefits of network centrality by exploring institutional contingencies. It further sheds on light the scope of the network centrality–innovation issue by extending its research context to Chinese entrepreneurial firms.

This study aims to focus on the grid connected inverter.

The grid connected inverter for harmonic suppression was designed, the topological structure of the inverter and the design of LCL filter were analyzed, then a PIR controller was proposed and finally simulation and experiment were carried out.

The simulation results showed that the distortion rates of the 5th, 7th and 11th harmonics under PIR control were 0.14%, 0.13% and 0.06%, respectively, which were significantly lower than that under PI control. The system test results also showed that the current waveform under PI control was rough and total harmonic distortion (THD) content was 3.8%; under PIR control, the grid connected current waveform was relatively smooth, with fewer spikes and burrs, and the THD content was 1.9%, indicating that the harmonics were effectively suppressed.

The experimental results verify that the inverter and PIR controller designed in this study are effective for harmonic suppression. This work makes some contributions to the improvement of the effect of harmonic suppression and promotion of the better application of grid connected inverter.