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The purpose of this article is to design and make fabrics with colorful melange yarns spun by a three-channel rotor spinning machine.

The three-channel digital rotor-spun machine controls the blending proportion by adjusting the feeding of three-primary color fiber slivers online, so that a piece of colorful yarn presents a variety of colors along the longitudinal direction where constant yarn linear density can be produced flexibly. Various fabric patterns can be produced by three-channel rotor-spun colorful melange yarn with different periods of color.

The fabric, made by the rotor-spun colorful melange yarn, is rich in color, clear in layers, soft in the hand and has a hazy three-dimensional effect. The product is environmentally friendly and saves energy.

An innovative idea to develop various colorful fabrics is proposed by combining their pattern with colorful melange yarn produced by a three-channel rotor spinning machine.

This study aims to represent a novel closed-form solutions method based on the product of the exponential model to solve the inverse kinematics of a robotic manipulator. In addition, this method is applied to master–slave control of the minimally invasive surgical (MIS) robot.

For MIS robotic inverse kinematics, the closed-form solutions based on the product of the exponential model of manipulators are divided into the RRR and RRT subproblems. Geometric and algebraic constraints are used as preconditions to solve two subproblems. In addition, several important coordinate systems are established on the surgical robot and master–slave mapping strategies are illustrated in detail. Finally, the MIS robot can realize master–slave control by combining closed-form solutions and master–slave mapping strategy.

The simulation of the instrument manipulator based on the RRR and RRT subproblems is executed to verify the correctness of the proposed closed-form solutions. The fact that the accuracy of the closed-form solutions is better than that of the compensation method is validated by the contrastive linear trajectory experiment, and the average and the maximum tracking errors are 0.1388 mm and 0.3047 mm, respectively. In the animal experiment, the average and maximum tracking error of the left instrument manipulator are 0.2192 mm and 0.4987 mm, whereas the average and maximum tracking error of the right instrument manipulator are 0.1885 mm and 0.6933 mm. The successful completion of the animal experiment comprehensively demonstrated the feasibility and reliability of the master–slave control strategy based on the novel closed-form solutions.

The proposed closed-form solutions are error-free in theory. The master–slave control strategy is not affected by calculation error when the closed-form solutions are used in the surgical robot. And the accuracy and reliability of the master–slave control strategy are greatly improved.

The purpose of this paper is to propose a control algorithm to improve the backdrivability performance of minimally invasive surgical robotic arms, so that precise manual manipulations of robotic arms can be performed in the preoperative operation.

First, the flexible-joint dynamic model of the 3-degree of freedom remote center motion (RCM) mechanisms of minimally invasive surgery (MIS) robot is derived and its dynamic parameters and friction parameters are identified. Next, the angular velocities and angular accelerations of joints are estimated in real time by the designed Kalman filter. Finally, a control algorithm based on Kalman filter is proposed to enhance the backdrivability of RCM mechanisms by compensating for the internally generated gravitational, frictional and inertial resistances experienced during the positioning and orientating.

The parameter identification for RCM mechanisms can be experimentally evaluated from comparison between the measured torques and the reconstructed torques. The accuracy and convergence of the real-time estimation of angular velocity and acceleration of the joint by the designed Kalman filter can be verified from corresponding simulation experiments. Manual adjustment experiments and animal experiments validate the effectiveness of the proposed backdrivability control algorithm.

The backdrivability control algorithm presented in this paper is a universal method to enhance the manual operation performance of robots, which can be used not only in the medical robot preoperative manual manipulation but also in robot haptic interaction, industrial robot direct teaching and active rehabilitation training of rehabilitation robot and so on.

Compared with other backdrivability design methods, the proposed algorithm achieves good backdrivability for RCM mechanisms without using force sensors and accelerometers. In addition, this paper presents a new static friction compensation approach for a joint moving with very low velocity.

Robot-assisted system for minimally invasive surgery (MIS) has been attracting more and more attentions. Compared with a traditional MIS, the robot-assisted system for MIS is able to overcome or reduce defects, such as poor hand-eye coordination, heavy labour intensity and limited motion of the instrument. The purpose of this paper is to design a novel robotic system for MIS applications.

A robotic system with three separate slave arms for MIS has been designed. In the proposed robot, a new mechanism was designed as the remote centre motion (RCM) mechanism to restrain the movement of instrument or laparoscope around the incision. Moreover, an improved instrument without coupling motion between wrist and grippers was developed to enhance its manipulability. A control system architecture was also developed, and an intuitive control method was applied to realize hand-eye coordination of the operator.

For the RCM mechanism, the workspace was analyzed and the positioning accuracy of the remote centre point was tested. The results show that the RCM mechanism can be applied to MIS. Furthermore, the master-slave trajectory tracking experiments reveal that slave robots are able to follow the movement of the master manipulators well. Finally, the feasibility of the robot-assisted system for MIS is proved by performing animal experiments successfully.

This paper offers a novel robotic system for MIS. It can accomplish the anticipated results.

Existing robot-assisted minimally invasive surgery (RMIS) system lacks of force feedback, and it cannot provide the surgeon with interaction forces between the surgical instruments and patient’s tissues. This paper aims to restore force sensation for the RMIS system and evaluate effect of force sensing in a master-slave manner.

This paper presents a four-DOF surgical instrument with modular joints and six-axis force sensing capability and proposes an incremental position mode master–slave control strategy based on separated position and orientation to reflect motion of the end of master manipulator to the end of surgical instrument. Ex-vivo experiments including tissue palpation and blunt dissection are conducted to verify the effect of force sensing for the surgical instrument. An experiment of trajectory tracking is carried out to test precision of the control strategy.

Results of trajectory tracking experiment show that this control strategy can precisely reflect the hand motion of the operator, and the results of the ex-vivo experiments including tissue palpation and blunt dissection illustrate that this surgical instrument can measure the six-axis interaction forces successfully for the RMIS.

This paper addresses the important role of force sensing and force feedback in RMIS, clarifies the feasibility to apply this instrument prototype in RMIS for force sensing and provides technical support of force feedback for further clinical application.

This paper aims to develop a novel miniature 3-axis force sensor which can detect the interaction forces during tissue palpation in MIS (minimally invasive surgery). MIS offers many significant merits compared with traditional open surgery, the wound to the patients and the postoperative pains are alleviated and reduced dramatically. However, the inherent drawback due to lack of force feedback still exists while conducting some operation procedures. For example, tissue palpation performed easily during open surgery could not be realized in an MIS manner.

The force sensor is based on the resistive-based sensing method that utilizes strain gauges to measure the strain when the external loads are acting on the tip of the sensor. A novel flexible tripod structure with bending and compression deformations is designed to discriminate the magnitudes and directions of the three orthogonal force components. A linear characteristic matrix is derived to disclose the relationship between the sensitivity and the geometric parameters of the structure, and a straightforward geometric parameterized optimization method considering the sensitivity isotropy is proposed to provide the sensor structure with high sensitivity and adequate stiffness.

The sensor prototype can perform force measurement with sensing ranges of ± 3.0 N in axial direction and ± 1.5 N in radial direction, and the resolutions are 5 per cent and 1 per cent, respectively. It is concluded that this force sensor is compatible with MIS instruments and the ex-vivo experiment shows that the sensor can be used to perform tissue palpation during MIS procedures.

This paper is intended to address the significant role of force sensing and force feedback during MIS operations, and presents a new application of the resistive-based sensing method in MIS. A tripod structure is designed and a straightforward optimization method considering the sensitivity isotropy of the sensor is proposed to determine geometric parameters suited for the given external loads.

The purpose of this paper is to examine the use of financial information and valuation methods among private equity funds in Europe and India. The authors analyze differences in the choice of valuation methods and how the use of financial information differs among funds in the UK, Pan Europe and India.

A survey approach was utilized in collecting proprietary data from European and Indian private equity funds. The data were classified according to fund type, country grouping, size, risk profile, labor cost and industry structure and analyzed using MANOVA and ANOVA.

The results show that the use of valuation models is relatively homogeneous across countries and that the use of financial information appears to be driven to a large extent by fund type and fund focus. The use of audited financial statements appears to increase as firms mature. Significant differences were found in standard financial adjustments between the two fund types and between the country groupings. Results based on labor cost are weakly significant whereas industry structure does not appear to have an impact on how fund managers evaluate investments.

The results indicate that fund managers adapt their decision‐making behavior according to investment type and risk. The authors argue that understanding asymmetrical and structural issues may potentially improve investment decision‐making processes. The main conclusion for researchers is that buy‐out and venture capital funds should not be combined as one asset class. Since a survey approach was used, the study is subject to the belief that fund managers do not internalize decisions well, which could reduce the effectiveness of the research design.

There are few studies in the areas covered by this paper due to the proprietary nature of the private equity industry. The results are important because they help in understanding how fund managers use decision aids such as financial statements and valuation techniques. A better understanding of current practices will help fund managers and fund sponsors in devising improved decision aids and processes, which ultimately may lead to fewer non‐performing investments. This is especially important in private equity since investment decisions are often irreversible and binary.

That the introduction of the Control system should have given rise to a considerable amount of criticism, both appreciative and adverse, was naturally to be expected. The appreciative remarks which have appeared in the press, and those also which have been privately communicated to the directors, indicate that the subject has been intelligently considered, and in some cases carefully investigated and studied. The opinions given are worth having on account of the position and influence of hose who have given them, and on account of the obvious freedom from bias which has characterised them. This is so far satisfactory, and goes to show that the success which has attended the working of the Control system abroad may well be expected to attend it in this country as soon as it is sufficiently well known to be appreciated by the manufacturers and vendors of good and genuine products, and by the general public, whose best interests it cannot but serve.

Gives an in depth view of the strategies pursued by the world’s leading chief executive officers in an attempt to provide guidance to new chief executives of today. Considers the marketing strategies employed, together with the organizational structures used and looks at the universal concepts that can be applied to any product. Uses anecdotal evidence to formulate a number of theories which can be used to compare your company with the best in the world. Presents initial survival strategies and then looks at ways companies can broaden their boundaries through manipulation and choice. Covers a huge variety of case studies and examples together with a substantial question and answer section.

Epidemiologists are concerned the next deadly global cognition will be a new kind of deadly flu which humans have no resistance. Since the 1960s, their alarm has been focused on a bird (avian) virus (H5N1). This virus is generally harmless in its host species, but it is extremely deadly when contracted by humans. H5N1 mutates quickly and tends to pick up genes from flu viruses that affect other species. The flu is far more contagious and harder to contain than the SARS (severe acute respiratory syndrome) virus. It is projected that 30‐40 per cent of the population would be infected in a H5N1 flu pandemic, and as many as one‐third would die. The 1918 Spanish flu caused 20 to 50 million deaths world wide. One scientist observed that the 1918 Spanish flu pandemic could have caused civilisation to disappear within a few weeks. Currently, more than 50 million chickens have been slaughtered in eight Asian countries in efforts to curb the spread of avian influenza. This article examines the roots and dangers of the potential avian influenza pandemic, examining the business and social ramifications that could ensue if the worst case scenario occurs.