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Article
Publication date: 9 April 2018

Bin Shi, Jian Hua Guo, Xing An Cao, En Zhu Hu and Kun Hong Hu

This paper aims to explore the effects of mineral diesel fuel carbon soot (MCS) and biodiesel carbon soot (BCS) on the lubrication of polyalphaolefin (PAO) and diesel fuels.

Abstract

Purpose

This paper aims to explore the effects of mineral diesel fuel carbon soot (MCS) and biodiesel carbon soot (BCS) on the lubrication of polyalphaolefin (PAO) and diesel fuels.

Design/methodology/approach

Two styles of carbon soot were prepared from the natural combustion of mineral diesel fuel oil (MDO) and biodiesel oil (BDO). Tribological tests were conducted on a high-frequency reciprocating rig. Friction surfaces were characterized using three-dimensional laser scanning confocal microscopy and Raman spectroscopy.

Findings

The addition of MCS and BCS to PAO could reduce friction in most cases. MCS had a negligible effect on the wear for contents not exceeding 1.0 per cent. By contrast, BCS exhibited a considerable negative influence on the wear resistance even at low contents. For diesel fuels, MCS reduced both friction and wear, whereas BCS substantially deteriorated the lubrication of BDO. MCS formed a Fe3O4/C composite lubricating film on the friction surface. BCS also entered the contact region, but it did not form an effective Fe3O4/C composite lubricating film.

Originality/value

This work compared MDO and BDO from a different perspective, i.e. the effects of their combustion carbon soot on the lubrication of lubricating oil and fuel oil. The significant negative effect of BCS on the lubrication of lubricating oil and BDO is a problem that could occur in the industrial application of BDO.

Details

Industrial Lubrication and Tribology, vol. 70 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 12 October 2012

Shi Hao‐bin, Yu Zhu‐jun, Xu You‐feng and Li Wei‐hua

The purpose of this paper is to establish a situation evaluation model of the robot and ball in SimuroSot5vs5 platforms and enhance the strength of the team in a SimuroSot5vs5.

Abstract

Purpose

The purpose of this paper is to establish a situation evaluation model of the robot and ball in SimuroSot5vs5 platforms and enhance the strength of the team in a SimuroSot5vs5.

Design/methodology/approach

This paper presents a mathematical model based on situation evaluations which can improve the strength of the team in SimuroSot5vs5. The situation evaluation focus on four aspects includes scores of both sides, possession of teams on ground, ball strategy, and treat. The statistical analysis of the score can verify validity and stability of current strategy in confrontation. To evaluate the situation more effectively without blindness, possession on both teams is, respectively, evaluated. Ball strategy analyzes coordinate transformation to the ball on the ground and illustrates the circumstance of both teams on the offensive position accurately in length and breadth. To know the circumstance on the field more completely and synthetically, a threat situation evaluation model is built. An effective and practical algorithm for comprehensive situation evaluation is successfully finished. The experiments prove validity and performance of the proposed situation evaluation model.

Findings

A mathematical model is designed to achieve situation evaluation, and the strategy can change in accordance with different situations on the ground.

Research limitations/implications

The system is specifically applied to SimuroSot5vs5 platform. The extensibility of the system is limited.

Practical implications

When the robot and ball is in high speed movement, a large calculated amount will slow the speed of the system.

Originality/value

The paper shows that situation evaluation in SimuroSot decision support systems will enhance the battle effectiveness of the soccer team.

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Article
Publication date: 1 December 2005

John L. Daniels, Raghuram Cherukuri, Helene A. Hilger, James D. Oliver and Shi Bin

The purpose of this paper is to evaluate the influence of a mixture of nutrient solution, bacteria and biofilm on the consolidation, unconfined compression and desiccation…

Abstract

Purpose

The purpose of this paper is to evaluate the influence of a mixture of nutrient solution, bacteria and biofilm on the consolidation, unconfined compression and desiccation characteristics of two soils that could be used in waste containment applications.

Design/methodology/approach

Experimental work was conducted to investigate the influence of biofilm on the desiccation, strength and consolidation characteristics of two barrier soils. The soils were evaluated with water alone and with a biofilm solution composed of nutrients, bacteria and exopolymeric substances (EPS). These solutions were mixed with a locally available clay (“red bull tallow” (RBT)) as well as a mix of 65 percent sand and 35 percent bentonite (65‐35 Mix).

Findings

Reductions in strength and increases in ductility are observed with biofilm amendment for two soil types. The shear strength was reduced from 413 to 313 kPa and from 198 to 179 kPa for RBT and 65‐35 Mix, respectively. Desiccation tests reveal an increase in moisture retention for early time increments in amended specimens, while both increases and decreases are noted after extended drying. Increases in the rate of consolidation and modest decreases in the compression and swell index were observed. In particular, the consolidation coefficient was increased from 0.036 to 0.064 cm2/min and from 0.060 to 0.093 cm2/min for RBT and 65‐35 Mix, respectively.

Practical implications

These results are useful in establishing the broader impacts of using biofilm as an additive to increase the performance (e.g. reduce hydraulic conductivity and increase resistance to crack formation) of barrier materials in waste containment applications. Moreover, the data provide insight into the geotechnical implications of biofilm‐producing methanotrophic activity that occurs naturally in the covers of municipal solid waste landfills.

Originality/value

Very little research has been published on the influence of biofilm on the behavior of barrier materials in general, and on geotechnical properties in particular. This paper is unique in making the connection between methanotrophic activity, soil modification and barrier material performance.

Details

Management of Environmental Quality: An International Journal, vol. 16 no. 6
Type: Research Article
ISSN: 1477-7835

Keywords

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Article
Publication date: 8 February 2021

Zhifeng Wang, Chi Zuo and Chunyan Zeng

Recently, the double joint photographic experts group (JPEG) compression detection tasks have been paid much more attention in the field of Web image forensics. Although…

Abstract

Purpose

Recently, the double joint photographic experts group (JPEG) compression detection tasks have been paid much more attention in the field of Web image forensics. Although there are several useful methods proposed for double JPEG compression detection when the quantization matrices are different in the primary and secondary compression processes, it is still a difficult problem when the quantization matrices are the same. Moreover, those methods for the different or the same quantization matrices are implemented in independent ways. The paper aims to build a new unified framework for detecting the doubly JPEG compression.

Design/methodology/approach

First, the Y channel of JPEG images is cut into 8 × 8 nonoverlapping blocks, and two groups of features that characterize the artifacts caused by doubly JPEG compression with the same and the different quantization matrices are extracted on those blocks. Then, the Riemannian manifold learning is applied for dimensionality reduction while preserving the local intrinsic structure of the features. Finally, a deep stack autoencoder network with seven layers is designed to detect the doubly JPEG compression.

Findings

Experimental results with different quality factors have shown that the proposed approach performs much better than the state-of-the-art approaches.

Practical implications

To verify the integrity and authenticity of Web images, the research of double JPEG compression detection is increasingly paid more attentions.

Originality/value

This paper aims to propose a unified framework to detect the double JPEG compression in the scenario whether the quantization matrix is different or not, which means this approach can be applied in more practical Web forensics tasks.

Details

International Journal of Web Information Systems, vol. 17 no. 2
Type: Research Article
ISSN: 1744-0084

Keywords

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Article
Publication date: 12 June 2018

Mingming Guo, Hua Zhang, Chuncheng Feng, Manlu Liu and Jianwen Huo

This paper aims to present a method to improve the sensitive and low probabilities of false alarm of a manipulator in a human–robot interaction environment, which can…

Abstract

Purpose

This paper aims to present a method to improve the sensitive and low probabilities of false alarm of a manipulator in a human–robot interaction environment, which can improve the performance of the system owing to non-linear uncertainty in the model of the robot controller.

Design/methodology/approach

A novel collision detection method based on adaptive residual estimation is proposed, promoting the detection accuracy of the collision of the manipulator during operation. First, a general momentum residual estimator is designed to incorporate the non-linear factors of the manipulator (e.g. joint friction, speed and acceleration) into the residual-related uncertainty of the model. Second, model parameters are estimated through gradient correction. The residual filter is used to determine the dynamic threshold, resulting in higher detection accuracy. Finally, the performance of the residual estimation scheme is evaluated by comparing the dynamic threshold with residual in real-time experiments where a single Universal Robot 5 robot end–effector collides with the obstacle.

Findings

Experimental results demonstrate that the collision detection system can improve sensitivity and lead to low probabilities of false alarm of non-linear uncertainty in the model.

Practical implications

The method proposed in this article can be applied to industry and human–robot interaction area.

Originality/value

An adaptive collision detection method is proposed in this paper to address non-linear uncertainties of the model in industrial application.

Details

Industrial Robot: An International Journal, vol. 45 no. 3
Type: Research Article
ISSN: 0143-991X

Keywords

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Book part
Publication date: 9 June 2016

Marc Owen Jones

Here, we examine the challenges to democratization in Bahrain, with a particular focus on how the recent 2011 Uprising has resulted in a deepening of authoritarianism. It…

Abstract

Here, we examine the challenges to democratization in Bahrain, with a particular focus on how the recent 2011 Uprising has resulted in a deepening of authoritarianism. It is argued that the recent unrest has brought into sharp relief the absence of “quality” democracy in Bahrain, and that any form of democratic transition is dependent on the will of a conservative Al Khalifa-Saudi nexus. While the pro-democracy movement may have prompted minor concessions on the part of the government, the extent of the popular mobilization triggered the Al Khalifa regime’s authoritarian reflex, and they have reacted to throttle the Uprising by putting in place legislative, ideological, and political barriers to reform, which points not only to a current de-democratization, but also a lack of future democratization. In addition to arguing for the post-2011 undoing of democracy in Bahrain, this paper also points to two major barriers to future democratization; (1) a conservative, post-Independence Al Khalifa-Saudi coalition assisted by large military resources (2) protracted communal tension brought about by the government’s instrumentalization of sectarianism.

Details

Protest, Social Movements and Global Democracy Since 2011: New Perspectives
Type: Book
ISBN: 978-1-78635-027-5

Keywords

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Article
Publication date: 27 January 2020

Renze Zhou, Zhiguo Xing, Haidou Wang, Zhongyu Piao, Yanfei Huang, Weiling Guo and Runbo Ma

With the development of deep learning-based analytical techniques, increased research has focused on fatigue data analysis methods based on deep learning, which are…

Abstract

Purpose

With the development of deep learning-based analytical techniques, increased research has focused on fatigue data analysis methods based on deep learning, which are gaining in popularity. However, the application of deep neural networks in the material science domain is mainly inhibited by data availability. In this paper, to overcome the difficulty of multifactor fatigue life prediction with small data sets,

Design/methodology/approach

A multiple neural network ensemble (MNNE) is used, and an MNNE with a general and flexible explicit function is developed to accurately quantify the complicated relationships hidden in multivariable data sets. Moreover, a variational autoencoder-based data generator is trained with small sample sets to expand the size of the training data set. A comparative study involving the proposed method and traditional models is performed. In addition, a filtering rule based on the R2 score is proposed and applied in the training process of the MNNE, and this approach has a beneficial effect on the prediction accuracy and generalization ability.

Findings

A comparative study involving the proposed method and traditional models is performed. The comparative experiment confirms that the use of hybrid data can improve the accuracy and generalization ability of the deep neural network and that the MNNE outperforms support vector machines, multilayer perceptron and deep neural network models based on the goodness of fit and robustness in the small sample case.

Practical implications

The experimental results imply that the proposed algorithm is a sophisticated and promising multivariate method for predicting the contact fatigue life of a coating when data availability is limited.

Originality/value

A data generated model based on variational autoencoder was used to make up lack of data. An MNNE method was proposed to apply in the small data case of fatigue life prediction.

Details

Anti-Corrosion Methods and Materials, vol. 67 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

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Article
Publication date: 5 February 2018

Ai Yue, Bin Tang, Yaojiang Shi, Jingjing Tang, Guanminjia Shang, Alexis Medina and Scott Rozelle

The purpose of this paper is to describe the policy and trends in rural education in China over the past 40 years; and also discuss a number of challenges that are faced…

Abstract

Purpose

The purpose of this paper is to describe the policy and trends in rural education in China over the past 40 years; and also discuss a number of challenges that are faced by China’s rural school system.

Design/methodology/approach

The authors use secondary data on policies and trends over the past 40 years for preschool, primary/junior high school, and high school.

Findings

The trends over the past 40 years in all areas of rural schooling have been continually upward and strong. While only a low share of rural children attended preschool in the 1980s, by 2014 more than 90 percent of rural children were attending. The biggest achievement in compulsory education is that the rise in the number of primary students that finish grade 6 and matriculate to junior high school. There also was a steep rise of those going to and completing high school. While the successes in upscaling rural education are absolutely unprecedented, there are still challenges.

Research limitations/implications

This is descriptive analysis and there is not causal link established between policies and rural schooling outcomes.

Practical implications

The authors illustrate one of the most rapid rises of rural education in history and match the achievements up with the policy efforts of the government. The authors also explore policy priorities that will be needed in the coming years to raise the quality of schooling.

Originality/value

This is the first paper that documents both the policies and the empirical trends of the success that China has created in building rural education from preschool to high school during the first 40 years of reform (1978-2018). The paper also documents – drawing on the literature and the own research – the achievements and challenges that China still face in the coming years, including issues of gender, urbanization, early childhood education and health and nutrition of students.

Details

China Agricultural Economic Review, vol. 10 no. 1
Type: Research Article
ISSN: 1756-137X

Keywords

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Article
Publication date: 10 December 2019

Cong Ding, Zhen-Yu Zhou, Zhi-Peng Yuan, Hua Zhu and Zhong-Yu Piao

The purpose of this paper is to study the correlation between the dynamic features of the running-in attractor and the wear particle group, so as to characterize the…

Abstract

Purpose

The purpose of this paper is to study the correlation between the dynamic features of the running-in attractor and the wear particle group, so as to characterize the running-in attractor by means of the wear particle group.

Design/methodology/approach

Wear particles are collected in phased wear experiments, and their dynamic features are investigated by the equivalent mean chord length L. Then, the correlation between the equivalent mean chord length L and the correlation dimension D of the running-in attractor is studied.

Findings

In the wear process, the equivalent means chord length L first decreases, then remains steady, and finally increases, this process agrees with the increase, stabilization and decrease of the correlation dimension D. Therefore, the wear particle group has a dynamic nature, which characterizes the formation, stabilization, and disappearance of a running-in attractor. Consequently, the dynamic characteristics and evolution of a running-in attractor can be revealed by the wear particle group.

Originality/value

The intrinsic relationship between the wear particle group and the running-in attractor is proved, and this is advantageous for further revealing the dynamic features of the running-in attractor and identifying the wear states.

Details

Industrial Lubrication and Tribology, vol. 72 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 8 June 2015

Avinash A. Thakre and Animesh Thakur

The purpose of this paper is to include investigation on extreme pressure lubrication behaviour of Al2O3 nanoparticles suspended in SAE20W40 lubricating oil. Effects of…

Abstract

Purpose

The purpose of this paper is to include investigation on extreme pressure lubrication behaviour of Al2O3 nanoparticles suspended in SAE20W40 lubricating oil. Effects of nanoparticles size (40-80 nm) and its concentration (0-1 per cent) on the coefficient of friction is studied using pin-on-disc tribotester.

Design/methodology/approach

Taguchi technique is used to optimize the process parameters for lower coefficient of friction. L18 orthogonal array involving six levels for one factor and three levels for remaining three factors is selected for the experimentation. The parameters selected for the study are sliding speed, normal load, nanoparticles size and its concentration in base oil.

Findings

It has been found that the presence of nanoparticles in proper concentration shows excellent tribological improvement in frictional characteristics compared to the base oil. The optimal combination of the parameters for minimum coefficient of friction is found to be 0.8 per cent concentration of 60 nm sized Al2O3 nanoparticles, 1,200 rpm sliding speed and 160 N of normal load. The mechanism of friction reduction in presence of nanoparticles is investigated using scanning electron microscopy.

Originality/value

This is the original work.

Details

Industrial Lubrication and Tribology, vol. 67 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

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