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Article
Publication date: 7 August 2017

Quanquan Liu, Chaoyang Shi, Bo Zhang, Chunbao Wang, Lihong Duan, Tongyang Sun, Xin Zhang, Weiguang Li, Zhengzhi Wu and Masakatsu G. Fujie

Paediatric congenital esophageal atresia surgery typically requires delicate and dexterous operations in a narrow and confined workspace. This study aims to develop a…

Abstract

Purpose

Paediatric congenital esophageal atresia surgery typically requires delicate and dexterous operations in a narrow and confined workspace. This study aims to develop a novel robot assisted surgical system to address these challenges.

Design/methodology/approach

The proposed surgical robot consists of two symmetrical slave arms with nine degree of freedoms each. Each slave arm uses a rigid-dexterous configuration and consists of a coarse positioning manipulator and a distal fine operation manipulator. A small Selective Compliance Assembly Robot Arm (SCARA) mechanism was designed to form the main component of the coarse positioning unit, ensuring to endure large forces along the vertical direction and meet the operational demands. The fine positioning manipulator applied the novel design using flexible shafts and universal joints to achieve delicate operations while possessing a high rigidity. The corresponding kinematics has been derived and then was validated by a co-simulation that was performed based on the combined use of Adams and MATLAB with considering the real robot mass information. Experimental evaluations for the tip positioning accuracy and the ring transfer tasks have been performed.

Findings

The simulation was performed to verify the correctness of the derived inverse kinematics and demonstrated the robot’s flexibility. The experimental results illustrated that the end-effector can achieve a positioning accuracy within 1.5 mm in a confined 30 × 30 × 30 mm workspace. The ring transfer task demonstrated that the surgical robot is capable of providing a solution for dexterous tissue intervention in a narrow workspace for paediatric surgery.

Originality/value

A novel and compact surgical assist robot is developed to support delicate operations by using the dexterous slave arm. The slave arm consists of a SCARA mechanism to avoid experiencing overload in the vertical direction and a tool manipulator driven by flexible shafts and universal joints to provide high dexterity for operating in a narrow workspace.

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Article
Publication date: 18 October 2019

Congcong Liu, Chong Wang, Keping Ye, Yun Bai, Xiaobo Yu, Chunbao Li and Guanghong Zhou

The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a…

Abstract

Purpose

The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a formation mechanism of PAHs in fat during electric roasting, which is a method of non-direct-contact-flame heating.

Design/methodology/approach

The effects of animal fats and model fat on the formation of PAHs were valued on the basis of the ultra high-performance liquid chromatography data. The corresponding products of the FAME pyrolysis were detected by TG-FTIR. The proposal formation mechanism of PAHs was based on the summary of the literature.

Findings

Contrary to the International Agency for Research on Cancer, DF had higher risk with 280.53 ng/g of concentration after being roasted than the others animal fats of red meat in terms of PAHs formation. This research also ensured the importance of fat on PAHs formation, the concentration of PAHs in pure fats was higher after being electric roasted than that in meat patties and juice which made from corresponding animal fat. What is more, during pure animal fats and meat products being processed, less PAHs formed in the fat with lower extent of unsaturation and lower content of linolenate. In the same way, methyl linolenate demonstrated the significant increasement to PAHs formation compared to the other fatty acids. And, the number of carbon atom and the extent of unsaturation in fatty acid affects the formation of PAHs during roasting. The detection of alkene and alkane allows to propose a formation mechanism of PAHs during model fat being heated. Further study is required to elucidate the confirm moleculars during the formation of PAHs.

Originality/value

This work studied the effect of the carbon atom number and the unsaturation extent of fats and model fats on the formation of PAHs. This work also assure the important of alkene and alkane on the pyrolysis of model fats. This study also researched the formation and distribution of PAHs in pure fats and meat products after being heated.

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Article
Publication date: 8 June 2012

Jiang Wu, Xiaobo Wang, Xianghui Zhao, Chunbao Zhang and Bo Gao

The purpose of this paper is to explore an application of computer‐aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as…

Abstract

Purpose

The purpose of this paper is to explore an application of computer‐aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as a prior stage to producing a sacrificial pattern for a removable partial denture (RPD) metal alloy framework.

Design/methodology/approach

With the introduction of laser scan technology and commercial reverse engineering software, a standard plaster maxillary dental cast with dentition defect was successfully scanned and created as a STL‐formatted digital cast. With the software, the unwanted undercuts were eliminated based on the desired path of insertion. Parts of the RPD framework were then successfully custom‐designed and combined as a whole.

Findings

A sacrificial pattern was produced by rapid prototyping (RP) method and finally casted with chromium cobalt alloy. With suitable finishing process, both the sacrificial pattern and the casted framework fitted the cast well.

Originality/value

The research indicated the feasibility of creating a library of RPD framework components. It is believed that, in the future, with the advance of the techniques, a totally new platform can be developed for the design and fabrication of custom‐fit RPD framework based on the CAD/CAM/RP system.

Details

Rapid Prototyping Journal, vol. 18 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 4 December 2017

Chunbao Liu, Weiyang Bu, Dong Xu, Yulong Lei and Xuesong Li

This paper aims to improve performance prediction and to acquire more detailed flow structures so as to analyze the turbulence in complex rotor-stator flow.

Abstract

Purpose

This paper aims to improve performance prediction and to acquire more detailed flow structures so as to analyze the turbulence in complex rotor-stator flow.

Design/methodology/approach

Hydraulic retarder as typical fluid machinery was numerically investigated by using hybrid Reynolds-averaged Navier–Stokes (RANS)/large eddy simulation (LES) models CIDDES Algebraic Wall-Modeled Large Eddy Simulation (LES) (WMLES) S-Ω and dynamic hybrid RANS/LES (DHRL). The prediction results were compared and analyzed with a RANS model shear stress transport (SST) k-omega which was a recommended choice in engineering.

Findings

The numerical results were verified by experiment and indicated that the predicted values for three hybrid turbulence models were more accurate. Then, the transient flow field was further analyzed visually in terms of turbulence statistics, Reynolds number, pressure-streamline, vortex structure and eddy viscosity ratio. The results indicated that HRL approaches could capture unsteady flow phenomena.

Practical implications

This study achieves both in performance prediction improvement and better flow mechanism understanding. The computational fluid dynamics (CFD) could be used instead of flow visualization to a certain extent. The improved CFD method, the fine computational grid and the reasonable simulation settings jointly enhance the application of CFD in the rotor-stator flow.

Originality/value

The improvement was quite encouraging compared with the reported literatures, contributing to the CFD playing a more important role in the flow machinery. DHRL provided the detailed explanation of flow transport between rotor and stator, which was not reported before. Through it, the flow mechanism can be better understood.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 27 no. 12
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 10 February 2021

Konghua Yang, Chunbao Liu, Jing Li and Jiawei Xiong

The flow phenomenon of particle image velocimetry has revealed the transition process of the complex multi-scale vortex between the boundary layer and mainstream region…

Abstract

Purpose

The flow phenomenon of particle image velocimetry has revealed the transition process of the complex multi-scale vortex between the boundary layer and mainstream region. Nonetheless, present computational fluid dynamics methods inadequately distinguish the discernable flows in detail. A multi-physical field coupling model, which was applied in rotor-stator fluid machinery (Umavathi, 2015; Syawitri et al., 2020), was put forward to ensure the identification of multi-scale vortexes and the improvement of performance prediction in torque converter.

Design/methodology/approach

A newly-developed multi-physical field simulation framework that coupled the scale-resolving simulation method with a dynamic modified viscosity coefficient was proposed to comparatively investigate the influence of energy exchange on thermal and flow characteristics and the description of the flow field in detail.

Findings

Regardless of whether quantitative or qualitative, its description ability on turbulence statistics, pressure-streamline, vortex structure and eddy viscosity ratio were visually experimentally and numerically analyzed. The results revealed that the modification of transmission medium viscous can identify flows more exactly between the viscous sublayer and outer boundary layer. Compared with RANS and large eddy simulation, a stress-blended eddy simulation model with a dynamic modified viscosity coefficient, which was further used to achieve blending on the stress level, can effectively solve the calculating problem of the transition region between the near-wall boundary layer and mainstream region.

Research limitations/implications

This indeed provides an excellent description of the transient flow field and vortex structure in different physical flow states. Furthermore, the experimental data has proven that the maximum error of the external performance prediction was less than 4%.

Originality/value

An improved model was applied to simulate and analyze the flow mechanism through the evolution of vortex structures in a working chamber, to deepen the designer with a fundamental understanding on how to reduce flow losses and flow non-uniformity in manufacturing.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0961-5539

Keywords

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Article
Publication date: 6 January 2021

Sa’d Shannak and Artem Malov

This paper aims to discuss opportunities for pairing the carbon dioxide (CO2) points of supply from stationary sources such as power plants, steel and cement production…

Abstract

Purpose

This paper aims to discuss opportunities for pairing the carbon dioxide (CO2) points of supply from stationary sources such as power plants, steel and cement production, coal to liquid plants and refineries, with potential oil reservoirs in China.

Design/methodology/approach

This study builds a linear optimization model to analyze the tradeoffs in developing CO2-enhance oil recovery (EOR) projects in China for a range of policy options to match points of supply with the points of demand (oil fields). The model works on optimizing CO2 application costs by meeting four principal components; CO2 storage, CO2 capture, transport costs and additional oil recovery.

Findings

This study reveals new opportunities and economic sources to feed CO2-EOR applications and offers reasonable options to supply CO2 for potential points of demand. Furthermore, power plants and coal to liquid industries had the most significant and economic contributions to potential CO2-EOR projects in China. Total annual emission reduction is expected to be 10% (based on 10 Gton annual emissions). The emission reductions and potential CO2 storage from the different industries as follow; 94% from power plants, 4% from biofuel and 2% from coal to liquid plants.

Social implications

Carbon capture and storage (CCS) is one practice aiming to reduce the amounts of anthropogenic emissions of carbon dioxide emitted into the atmosphere and reduce the related social costs. However, given the relatively high cost associated with this practice, coupling it with EOR could offer a significant financial incentive to facilitate the development of CCS projects and meet climate change objectives.

Originality/value

The model used in this study can be straightforwardly adapted to any geographic location where industry and policymakers are looking to simultaneously reduce CO2 emissions while increasing hydrocarbon recovery. The model is highly adaptable to local values in the parameters considered and to include additional local considerations such as geographic variation in capture costs, taxes and premiums to be placed on CO2 capture in so-called “non-attainment zones” where pollution capture make could make a project politically and economically viable. Regardless of how and where this model is applied, it is apparent that CO2 from industrial sources has substantial potential value as a coproduct that offsets its sequestration costs using existing, commercially available CO2-EOR technology, once sources and sinks are optimally paired.

Details

Journal of Science and Technology Policy Management, vol. 12 no. 1
Type: Research Article
ISSN: 2053-4620

Keywords

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Article
Publication date: 31 March 2020

Shishir Goyal, Aman Agarwal and Srikanta Routroy

The objective of this paper is to compare and evaluate the environmental performance of steel supply chains considering relevant environmental loss factors using Taguchi…

Abstract

Purpose

The objective of this paper is to compare and evaluate the environmental performance of steel supply chains considering relevant environmental loss factors using Taguchi loss function (TLF) and design of experiments (DOE).

Design/methodology/approach

The different environmental loss factors in steel manufacturing supply chain were studied and the significant factors were identified. Their combined contributions along the significant factors were estimated using TLF and DOEs comparing environment losses at different scenarios.

Findings

The proposed methodology using TLF and DOEs was applied to three Indian steel manufacturing companies (Company A, Company B and Company C). The Company A with minimal average environmental loss score is found to be operating its supply chain with higher efficiency and has better environmental performance compared to the other two companies (B and C).

Research limitations/implications

The results obtained are based on the study carried out in three Indian steel manufacturing companies. Therefore, the results cannot be generalized.

Practical implications

This paper will definitely show the direction for comparative environmental performance assessment of manufacturing industries in general and steel industries in specific considering environmental loss factors and environmental conditions. It determines individual performance across each environmental loss factor and their combined impact.

Originality/value

Although there is a need to have comparative performance analysis with respect to environmental losses among steel companies in developing countries such as India, but hardly any study has been reported in this direction. This work will definitely add the value to the supply chain literature in general and environment losses in steel manufacturing supply chain in specific.

Details

Journal of Enterprise Information Management, vol. 33 no. 3
Type: Research Article
ISSN: 1741-0398

Keywords

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