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Article
Publication date: 8 February 2021

Bo Pan, Xiao Yi Yang and Rui Hua Yang

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

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

International Journal of Clothing Science and Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0955-6222

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Article
Publication date: 13 August 2020

Kun Li, Shuai Ji, Guojun Niu, Yue Ai, Bo Pan and Yili Fu

Existing robot-assisted minimally invasive surgery (RMIS) system lacks of force feedback, and it cannot provide the surgeon with interaction forces between the surgical…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 6
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 13 December 2017

Shuizhong Zou, Bo Pan, Yili Fu and Shuixiang Guo

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Originality/value

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.

Details

Industrial Robot: An International Journal, vol. 45 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 15 May 2017

Yue Ai, Bo Pan, Yili Fu and Shuguo Wang

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Details

Industrial Robot: An International Journal, vol. 44 no. 3
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 16 March 2015

Kun Li, Bo Pan, Juncheng Zhan, Wenpeng Gao, Yili Fu and Shuguo Wang

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Sensor Review, vol. 35 no. 2
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 22 February 2011

Jan Smolarski, Neil Wilner and Weifang Yang

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…

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Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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.

Originality/value

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.

Details

Review of Accounting and Finance, vol. 10 no. 1
Type: Research Article
ISSN: 1475-7702

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Article
Publication date: 1 March 1899

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…

Abstract

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.

Details

British Food Journal, vol. 1 no. 3
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 1 June 1999

George K. Chacko

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…

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7217

Abstract

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.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 11 no. 2/3
Type: Research Article
ISSN: 1355-5855

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Article
Publication date: 1 June 2005

John Overby, Mike Rayburn, David C. Wyld and Kevin Hammond

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…

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1117

Abstract

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.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 17 no. 2
Type: Research Article
ISSN: 1355-5855

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Article
Publication date: 1 June 1900

The decision of the Wolverhampton Stipendiary in the case of “Skim‐milk Cheese” is, at any rate, clearly put. It is a trial case, and, like most trial cases, the reasons…

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51

Abstract

The decision of the Wolverhampton Stipendiary in the case of “Skim‐milk Cheese” is, at any rate, clearly put. It is a trial case, and, like most trial cases, the reasons for the judgment have to be based upon first principles of common‐sense, occasionally aided, but more often complicated, by already existing laws, which apply more or less to the case under discussion. The weak point in this particular case is the law which has just come into force, in which cheese is defined as the substance “usually known as cheese” by the public and any others interested in cheese. This reliance upon the popular fancy reads almost like our Government's war policy and “the man in the street,” and is a shining example of a trustful belief in the average common‐sense. Unfortunately, the general public have no direct voice in a police court, and so the “usually known as cheese” phrase is translated according to the fancy and taste of the officials and defending solicitors who may happen to be concerned with any particular case. Not having the general public to consult, the officials in this case had a war of dictionaries which would have gladdened the heart of Dr. JOHNSON; and the outcome of much travail was the following definition: cheese is “ coagulated milk or curd pressed into a solid mass.” So far so good, but immediately a second definition question cropped up—namely, What is “milk?”—and it is at this point that the mistake occurred. There is no legal definition of new milk, but it has been decided, and is accepted without dispute, that the single word “milk” means an article of well‐recognised general properties, and which has a lower limit of composition below which it ceases to be correctly described by the one word “milk,” and has to be called “skim‐milk,” “separated milk,” “ milk and water,” or other distinguishing names. The lower limits of fat and solids‐not‐fat are recognised universally by reputable public analysts, but there has been no upper limit of fat fixed. Therefore, by the very definition quoted by the stipendiary, an article made from “skim‐milk” is not cheese, for “skim‐milk” is not “milk.” The argument that Stilton cheese is not cheese because there is too much fat would not hold, for there is no legal upper limit for fat; but if it did hold, it does not matter, for it can be, and is, sold as “Stilton” cheese, without any hardship to anyone. The last suggestion made by the stipendiary would, if carried out, afford some protection to the general public against their being cheated when they buy cheese. This suggestion is that the Board of Agriculture, who by the Act of 1899 have the legal power, should determine a lower limit of fat which can be present in cheese made from milk; but, as we have repeatedly pointed out, it is by the adoption of the Control system that such questions can alone be settled to the advantage of the producer of genuine articles and to that of the public.

Details

British Food Journal, vol. 2 no. 6
Type: Research Article
ISSN: 0007-070X

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