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This study aims to determine the most similar set of recommendation books to the user selections in LibraryThing.

For this purpose, 30,000 tags related to History on the LibraryThing have been selected. Their tags and the tags of the related recommended books were extracted from three different recommendations sections on LibraryThing. Then, four similarity criteria of Jaccard coefficient, Cosine similarity, Dice coefficient and Pearson correlation coefficient were used to calculate the similarity between the tags. To determine the most similar recommended section, the best similarity criterion had to be determined first. So, a researcher-made questionnaire was provided to History experts.

The results showed that the Jaccard coefficient, with a frequency of 32.81, is the best similarity criterion from the point of view of History experts. Besides, the degree of similarity in LibraryThing recommendations section according to this criterion is equal to 0.256, in the section of books with similar library subjects and classifications is 0.163 and in the Member recommendations section is 0.152. Based on the findings of this study, the LibraryThing recommendations section has succeeded in introducing the most similar books to the selected book compared to the other two sections.

To the best of the authors’ knowledge, itis for the first time, three sections of LibraryThing recommendations are compared by four different similarity criteria to show which sections would be more beneficial for the user browsing. The results showed that machine recommendations work better than humans.

Molecular dynamics is an emerging simulation technique in the field of machining in recent years. Many researchers have tried to simulate different processing methods of various materials with the theory of molecular dynamics (MD), and some preliminary conclusions have been obtained. However, the application of MD simulation is more limited compared with traditional finite element model (FEM) simulation technique due to the complex modeling approach and long computation time. Therefore, more studies on the MD simulations are required to provide a reliable theoretical basis for the nanoscale interpretation of grinding process. This study investigates the crystal structures, dislocations, force, temperature and subsurface damage (SSD) in the grinding of iron-nickel alloy using MD analysis.

In this study the simulation model is established on the basis of the workpiece and single cubic boron nitride (CBN) grit with embedded atom method and Morse potentials describing the forces and energies between different atoms. The effects of grinding parameters on the material microstructure are studied based on the simulation results.

When CBN grit goes through one of the grains, the arrangement of atoms within the grain will be disordered, but other grains will not be easily deformed due to the protection of the grain boundaries. Higher grinding speed and larger cutting depth can cause greater impact of grit on the atoms, and more body-centered cubic (BCC) structures will be destroyed. The dislocations will appear in grain boundaries due to the rearrangement of atoms in grinding. The increase of grinding speed results in the more transformation from BCC to amorphous structures.

This study is aimed to study the grinding of Fe-Ni alloy (maraging steel) with single grit through MD simulation method, and to reveal the microstructure evolution within the affected range of SSD layer in the workpiece. The simulation model of polycrystalline structure of Fe-Ni maraging steel and grinding process of single CBN grit is constructed based on the Voronoi algorithm. The atomic accumulation, transformation of crystal structures, evolution of dislocations as well as the generation of SSD are discussed according to the simulation results.

In my experience of teaching Technical Drawing and Geometrical and Engineering Drawing over the past few years, I have noticed that when I arrive at the ‘Loci of Points in Mechanisms and Elementary Linkwork’ part of the syllabus, the pupils have difficulty in ‘seeing’ and understanding the various motions of the mechanisms and linkwork concerned. Of course, one can make a carefully drawn diagram for each example on the blackboard and let them learn it parrot fashion, but this is hardly what a good teacher aims at. It is much better for the pupil to comprehend fully what happens when each part of the mechanism or linkwork moves, and to see exactly where and how the locus is obtained.

Demonstrates the modelling of the kinetic process when the sewing needle enters the fabric. To get an adequate mechanical model of the given problem, the function ‐ the mathematical model ‐ of the penetration force with respect to the fabric, the needle and the mechanism in the sewing machine must be developed. The fabric was modelled as a combination of warp and weft threads. Each thread from the fabric is modelled as an ideal elastic Hook’s material. Outlines the restrictions which needed to be made to get the mathematical model of the problem.

The rope-climbing robot that can cling to a rope for locomotion has been a popular piece of equipment for some overhead applications due to its high flexibility. In view of problems left by existing rope-climbing robots, this paper aims to propose a new-style rope-climbing robot named Finger-wheeled mechanism robot (FWMR)-II to improve their performance.

FWMR-II adopts a modular and link-type mechanical structure. With the finger-wheeled mechanism (FWM) module, the robot can achieve smooth and quick locomotion and good capability of obstacle-crossing on the rope and with the link module based on a spatial parallel mechanism, the robot adaptability for rope environments is improved further. The kinematic models that can present configurations of the FWM module and link module of the robot are established and for typical states of the obstacle-crossing process, the geometric definitions and constraints that can present the robot position relative to the rope are established. The simulation is performed with the optimization calculating method to obtain the robot adaptability for rope environments and the experiment is also conducted with the developed prototype to verify the robot performance.

From the simulation results, the adaptability for rope environments of FWMR-II are obtained and the advantage of FWMR-II compared with FWMR-I is also proved. The experiment results give a further verification for the robot design and analysis work.

The robot proposed in this study can be used for inspection of power transmission lines, inspection and delivery in mine and some other overhead applications.

An ingenious modular link-type robot is proposed to improve existing rope-climbing robots and the method established in this study is worthy of reference for obstacle-crossing analysis of other rope-climbing robots.

The purpose of this paper is to describe and evaluate the time-varying and coupling dynamic characteristics of a 3-DOF parallel tool head.

From the view of control, a new dynamic index of a 3-DOF parallel tool head is proposed based on the dynamic model in the joint space. This index can reflect the time-varying and coupling dynamic characteristics which are the main characteristics of the parallel mechanisms, and its distribution in the whole workspace is also given. Through comparison of the dynamic load (driving current) of each driving shaft, a series of experiments is designed and carried out on a prototype to validate the effectiveness of the dynamic analysis. The tracking error of each driving shaft has also been taken into consideration.

The simulations of the index have the same variation law with the experimental results. The dynamic load of the driving shaft becomes larger with the increase of the dynamic index, and the dynamic performance becomes worse at the same time.

The main dynamic characteristics of the 3-DOF parallel tool head can be described and evaluated through this work.

The purpose of this paper is to address the synthesis and experimental application of a generalized predictive control (GPC) technique on an Orthoglide robot.

The control strategy is composed of two control loops. The inner loop aims at linearizing the nonlinear robot dynamics using feedback linearization. The outer loop tracks the desired trajectory based on GPC strategy, which is robustified against measurement noise and neglected dynamics using Youla parameterization.

The experimental results show the benefits of the robustified predictive control strategy on the dynamical performance of the Orthoglide robot in terms of tracking accuracy, disturbance rejection, attenuation of noise acting on the control signal and parameter variation without increasing the computational complexity.

The paper shows the implementation of the robustified predictive control strategy in real time with low computational complexity on the Orthoglide robot.

The purpose of this paper is to discuss an example of modelling with experiments of robot prototype with dependent joint concept, including a full description of related functionalities. Reduction in active degrees of freedom in a machine can lead to improved accuracy, improved reliability and lower cost. The reconfiguration of machines and systems is a key technology for future responsive manufacturing systems. The concept of dependent joints helps to implement much specified sub-workspaces depending on functional needs in the machine.

This is inherently made possible using smart mechanical concepts having embedded sensors and reconfigurable control systems. This paper introduces structural reconfiguration systems and discusses a sample approach to functional reconfiguration.

A successful manipulator design with extended features when considering reduction in active degrees of freedom in a machine would lead to specific sub-workspace with improved accuracy, improved reliability and lower cost.

Reduction in active degrees of freedom in a machine can lead not only towards a dedicated functional workspace but also towards improved accuracy, improved reliability and lower cost.

This paper is of value to engineers and researchers developing robotic manipulators for use in various aspects of industry.

The paper aims to present a modeling method for multi‐layer, multi‐material printed circuit boards (PCBs) in both micro‐structure and board levels.

The method incorporates a multilayer finite element model that is established in two parts: the first part is an elasto‐plastic damaging model, which is presented to model metallic plies in the multi‐layer PCBs, while the second is a bi‐phase model for glass‐fiber/epoxy‐resin composite ply with fiber/matrix structure.

Numerous composite parts and complex material properties of multi‐layer PCBs complicate the reliability of the simulation. Therefore, the board level simulation and the micro‐structure modeling cannot be performed at the same time. A multi‐layer FEM code can solve this problem: with the use of bi‐phase and elasto‐plastic plies in this code, the micro‐structure and board‐level modeling for multi‐layer PCBs can be incorporated.

With the implementation of a virtual boundary method, the current multi‐layer model can be combined with the unit‐cell modeling method to perform detailed analysis at the micro‐structure level.

This paper presents a method for multi‐layer PCB modeling at both the micro‐structure and board levels. It provides a way to individually design the fabric types and the properties of glass fibers, epoxy resin, and copper foil in PCBs, to meet specific reliability requirements. With the proposed modeling, the static and shock responses of optimized PCBs can be analyzed with less computation.

This paper aims to present an adaptive sliding mode control (ASMC) for tunnel boring machine cutterhead telescopic system with uncertainties to achieve a high-precision trajectory in complex strata. This method could be applied to solve the problems caused by linear and nonlinear model uncertainties.

First, an integral-type sliding surface is defined to reduce the static tracking error. Second, a projection type adaptation law is designed to approximate the linear and nonlinear redefined parameters of the electrohydraulic system. Third, a nonlinear robust term with a continuous approximation function is presented for handling load force uncertainty and reducing sliding mode chattering. Moreover, Lyapunov theory is applied to guarantee the stability of the closed-loop system. Finally, the effectiveness of the proposed controller is proved by comparative experiments on a scaled test rig.

The linear and nonlinear model uncertainties lead to large variations in the dynamics of the mechanism and the tracking error. To achieve precise position tracking, an adaptation law was integrated into the sliding mode control which compensated for model uncertainties. Besides, the inherent sliding mode chattering was reduced by a continuous approximation function, while load force uncertainty was solved by a nonlinear robust feedback. Therefore, a novel ASMC for tunnel boring machine cutterhead telescopic system with uncertainties can improve its tracking precision and reduce the sliding mode chattering.

To the best of the authors’ knowledge, the ASMC is proposed for the first time to control the tunnel boring machine cutterhead telescopic system with uncertainties. The presented control is effective not only in control accuracy but also in parameter uncertainty.