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Article
Publication date: 1 May 2006

Kinshuk and Nian-Shing Chen

Abstract

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Campus-Wide Information Systems, vol. 23 no. 3
Type: Research Article
ISSN: 1065-0741

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Article
Publication date: 17 June 2008

Chen Wu, Xiaohua Hu and Jingyu Yang

The purpose of this paper is to construct diverse granules and coverings derived from a semi‐equivalence class and then to reveal the relationships between granules and…

Abstract

Purpose

The purpose of this paper is to construct diverse granules and coverings derived from a semi‐equivalence class and then to reveal the relationships between granules and coverings and even relations, and to help one to study pansystems relations in a trans‐cross view.

Design/methodology/approach

Forms regarding semi‐equivalence classes as primitives, blocks or granules such as tolerance class, join class, meet class, optimist/pessimist selected compatible class, and tolerantly kernel class in an incomplete information system are defined and compared. Different approximations are also introduced. Furthermore, diverse coverings are also suggested.

Findings

A tolerance class of an object is proved to be the join of semi‐equivalence classes containing it, i.e. a result of acting union operation on some primitive classes. A compatibly kernel class of an object is a meet of semi‐equivalence classes including it, i.e. a result of acting intersection operation on some primitive classes. Related coverings can also be regarded as coverings derived from the covering consisting of primitive granules. Several necessary and/or sufficient conditions for a general covering to become a semi‐equivalence or complete covering are obtained. Meaningful property and relationship results are also exploited.

Practical implications

Constructing diverse granules naturally from an incomplete information system to form a different knowledge expression system looks promising for data mining in the information society. It widens the approach and schema.

Originality/value

The paper shows that the formation process of granules is natural, newly defined, and not similar and theoretic to those existing in a neighborhood system. The relationship between diverse granules and coverings is described by mathematical theorems in sufficient or necessary condition form.

Details

Kybernetes, vol. 37 no. 6
Type: Research Article
ISSN: 0368-492X

Keywords

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Article
Publication date: 18 January 2016

Huajun Liu, Cailing Wang and Jingyu Yang

– This paper aims to present a novel scheme of multiple vanishing points (VPs) estimation and corresponding lanes identification.

Abstract

Purpose

This paper aims to present a novel scheme of multiple vanishing points (VPs) estimation and corresponding lanes identification.

Design/methodology/approach

The scheme proposed here includes two main stages: VPs estimation and lane identification. VPs estimation based on vanishing direction hypothesis and Bayesian posterior probability estimation in the image Hough space is a foremost contribution, and then VPs are estimated through an optimal objective function. In lane identification stage, the selected linear samples supervised by estimated VPs are clustered based on the gradient direction of linear features to separate lanes, and finally all the lanes are identified through an identification function.

Findings

The scheme and algorithms are tested on real data sets collected from an intelligent vehicle. It is more efficient and more accurate than recent similar methods for structured road, and especially multiple VPs identification and estimation of branch road can be achieved and lanes of branch road can be identified for complex scenarios based on Bayesian posterior probability verification framework. Experimental results demonstrate VPs, and lanes are practical for challenging structured and semi-structured complex road scenarios.

Originality/value

A Bayesian posterior probability verification framework is proposed to estimate multiple VPs and corresponding lanes for road scene understanding of structured or semi-structured road monocular images on intelligent vehicles.

Details

Industrial Robot: An International Journal, vol. 43 no. 1
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 23 August 2011

Cailing Wang, Chunxia Zhao and Jingyu Yang

Positioning is a key task in most field robotics applications but can be very challenging in GPS‐denied or high‐slip environments. The purpose of this paper is to describe…

Abstract

Purpose

Positioning is a key task in most field robotics applications but can be very challenging in GPS‐denied or high‐slip environments. The purpose of this paper is to describe a visual odometry strategy using only one camera in country roads.

Design/methodology/approach

This monocular odometery system uses as input only those images provided by a single camera mounted on the roof of the vehicle and the framework is composed of three main parts: image motion estimation, ego‐motion computation and visual odometry. The image motion is estimated based on a hyper‐complex wavelet phase‐derived optical flow field. The ego‐motion of the vehicle is computed by a blocked RANdom SAmple Consensus algorithm and a maximum likelihood estimator based on a 4‐degrees of freedom motion model. These as instantaneous ego‐motion measurements are used to update the vehicle trajectory according to a dead‐reckoning model and unscented Kalman filter.

Findings

The authors' proposed framework and algorithms are validated on videos from a real automotive platform. Furthermore, the recovered trajectory is superimposed onto a digital map, and the localization results from this method are compared to the ground truth measured with a GPS/INS joint system. These experimental results indicate that the framework and the algorithms are effective.

Originality/value

The effective framework and algorithms for visual odometry using only one camera in country roads are introduced in this paper.

Details

Industrial Robot: An International Journal, vol. 38 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 31 July 2020

Jingyu Pei, Xiaoping Wang, Leen Zhang, Yu Zhou and Jinyuan Qian

This paper aims to provide a series of new methods for projecting a three-dimensional (3D) object onto a free-form surface. The projection algorithms presented can be…

Abstract

Purpose

This paper aims to provide a series of new methods for projecting a three-dimensional (3D) object onto a free-form surface. The projection algorithms presented can be divided into three types, namely, orthogonal, perspective and parallel projection.

Design/methodology/approach

For parametric surfaces, the computing strategy of the algorithm is to obtain an approximate solution by using a geometric algorithm, then improve the accuracy of the approximate solution using the Newton–Raphson iteration. For perspective projection and parallel projection on an implicit surface, the strategy replaces Newton–Raphson iteration by multi-segment tracing. The implementation takes two mesh objects as an example of calculating an image projected onto parametric and implicit surfaces. Moreover, a comparison is made for orthogonal projections with Hu’s and Liu’s methods.

Findings

The results show that the new method can solve the 3D objects projection problem in an effective manner. For orthogonal projection, the time taken by the new method is substantially less than that required for Hu’s method. The new method is also more accurate and faster than Liu’s approach, particularly when the 3D object has a large number of points.

Originality/value

The algorithms presented in this paper can be applied in many industrial applications such as computer aided design, computer graphics and computer vision.

Details

Engineering Computations, vol. 38 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 17 May 2021

Jingyu Yu, Jingfeng Wang, Zhengmao Hua and Xingxing Wang

Airports are booming in China, to enlarge their capacities and stimulate economic development. Large-span spatial steel structures are commonly used in the terminal…

Abstract

Purpose

Airports are booming in China, to enlarge their capacities and stimulate economic development. Large-span spatial steel structures are commonly used in the terminal buildings of airport projects. Their advantages include prefabrication, strength, usability, adaptability and aesthetic quality. To manage large-span spatial steel structure projects, building information modeling (BIM) is recommended. Although there are plenty of studies on BIM application in steel structure projects, it is still rare to apply BIM to optimize the schedule and cost of steel structures, especially for airport projects.

Design/methodology/approach

This paper aims to develop a framework in which BIM and a time-cost optimization model are integrated to optimize construction costs and the duration of large-span spatial steel structure projects. A real case study was conducted to verify the feasibility of the BIM-based time-cost optimization model in an airport terminal building, which was built with a large-span spatial steel structure.

Findings

The results preliminarily support the reliability of the proposed BIM-based time-cost optimization model. The BIM-based time-cost optimization model will benefit construction planning for professionals and enrich relevant research on the application of BIM in large-span spatial steel structure projects.

Originality/value

The steel structure is difficult to control budgets and progress. This paper is expected to be adopted for optimizing the time and cost plans for projects involving steel structures in airport terminal buildings.

Details

Journal of Facilities Management , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1472-5967

Keywords

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Article
Publication date: 28 January 2014

Mei-Yung Leung and Jingyu Yu

The use of public engagement (PE) has been encouraged by the Hong Kong government in recent years, with the construction industry under particular pressure to employ it…

Abstract

Purpose

The use of public engagement (PE) has been encouraged by the Hong Kong government in recent years, with the construction industry under particular pressure to employ it. However, society as a whole has been suffering as a result of various levels of discontent and conflict in many construction development projects. The logical paths to analyze public need and resolve conflict in the PE process are vague. Value methodology (VM), a logical method, is thus proposed as an initial framework to support PE activities in construction projects. The purpose of this paper is to enhance PE performance for the complicated construction development projects with the application of VM principles.

Design/methodology/approach

Based on an extensive literature review, PE logical team process factors and PE outcomes were identified. A questionnaire survey was conducted to investigate the relationships between the logical PE team decision-making process (VM application in the logical process and team behaviors) and final PE outcomes.

Findings

The results showed that the PE team process with the application of VM, especially information and analysis phases, influenced PE outcomes positively. Conflict (both destructive conflict and constructive conflict) influenced PE outcomes in different directions.

Practical implications

It is recommended that the information and analysis phases of VM are applied to PE process in order to achieve consensus, cultivate team spirit, improve project performance, and enhance organizational reputation.

Originality/value

This paper innovatively proposes the application of VM into the PE team process in order to analyze the project logically and subsequently improve holistic PE project performance and finally promote social cohesion.

Details

Built Environment Project and Asset Management, vol. 4 no. 1
Type: Research Article
ISSN: 2044-124X

Keywords

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Article
Publication date: 12 August 2014

Cijun Shuai, Jingyu Zhuang, Shuping Peng and Xuejun Wen

The paper aims to fabricate an α-tricalcium phosphate (TCP) scaffold with an interconnected porous structure via selective laser sintering (SLS). To inhibit the phase…

Abstract

Purpose

The paper aims to fabricate an α-tricalcium phosphate (TCP) scaffold with an interconnected porous structure via selective laser sintering (SLS). To inhibit the phase transformation from β- to α-TCP in fabrication process of porous scaffolds, a small amount (1 weight per cent) of poly (L-lactic acid) (PLLA) is added into β-TCP powder to introduce the transient liquid phase.

Design/methodology/approach

The paper opted for the transient liquid phase of melting PLLA to decrease the sintering temperature in SLS. Meanwhile, the densification of β-TCP is enhanced with a combined effect of the capillary force caused by melting PLLA and the surface energy of β-TCP particles. Moreover, the PLLA will gradually decompose and completely disappear with laser irradiation.

Findings

The testing results show the addition of PLLA enables the scaffolds to achieve a higher β-TCP content of 77 ± 1.49 weight per cent compared with the scaffold sintered from β-TCP powder (60 ± 1.65 weight per cent), when the laser energy density is 0.4 J/mm2. The paper provides the mechanism of PLLA inhibition on the phase transformation from β- to α-TCP. And the optimum sintering parameters are obtained based on experimental results, which are used to prepare a TCP scaffold with an interconnected porous structure via SLS.

Research limitations/implications

This paper shows that the laser energy density is an important sintering parameter that can provide the means to control the micro-porous structure of the scaffold. If the laser energy density is too low, the densification is not enough. On the other hand, if the laser energy density is too high, the microcracks are observed which are attributed to the volume expansion during the phase transformation from β- to α-TCP. Therefore, the laser energy density must be optimized.

Originality/value

The paper provides a feasible method for fabricating TCP artificial bone scaffold with good biological and mechanical properties.

Details

Rapid Prototyping Journal, vol. 20 no. 5
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 21 March 2016

Chao Wang, Heyang Yu, Ni Zhan, Xubing Kang and Jingyu Zhang

The purpose of this paper is to develop a new vibration probe sensor for measurement of particle mass flow rate in gas–solid two phase flow.

Abstract

Purpose

The purpose of this paper is to develop a new vibration probe sensor for measurement of particle mass flow rate in gas–solid two phase flow.

Design/methodology/approach

A new vibration probe sensor based on polyvinylidene fluoride (PVDF) piezoelectric film is designed. The particle impact model according to Hertz contacting theory is presented. The average amplitude, standard deviation and spectral peak at the natural frequency of the probe (21.2 kHz) of the signals acquired through experiments are chosen as characteristic quantities for further analysis.

Findings

Through experimental study of relation between three characteristic quantities and the mass flow rate and air flow velocity, a good regularity is found in the average amplitude and the spectral peaks at natural frequency of the probe. According to the particle impact model, the structure of quantitative model is built and parameters of two models are calculated from experimental data. Additionally, tests are made to estimate mass flow rate. The average errors are 5.85 and 4.26 per cent, while the maximum errors are 10.81 and 8.65 per cent. The spectral peak at natural frequency of the probe is more applicable for mass flow rate measurement.

Practical implications

The sensor designed and the quantitative models established may be used in dilute phase pneumatic conveying lines of coal-fired power plants, cement manufacturing facilities and so on.

Originality/value

First, the new sensor is designed and the quantitative models are established. Second, the spectral peak at natural frequency of the probe is found that can be used for measurement of mass flow rate.

Details

Sensor Review, vol. 36 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 2 April 2019

Jingyu Yu, Guixia Ma and Shaoxing Cai

Aging-friendly environments have been encouraged to develop at the city level, district level and community level in China. In the process of rapid urbanization, the state…

Abstract

Purpose

Aging-friendly environments have been encouraged to develop at the city level, district level and community level in China. In the process of rapid urbanization, the state of aging-friendly communities in old and new neighborhoods is disparate. Hence, the purpose of this paper is to investigate aging-friendly communities and identify the disparities in old and new neighborhoods.

Design/methodology/approach

A total of 1,172 elderly respondents completed the survey. Of these, 576 seniors lived in an old community developed before 2000, and 596 lived in a new community developed after 2000. In total, 17 physical environment factors and 10 social environment factors were identified.

Findings

The results indicated that public spaces, facilities and transportation in old neighborhoods were inferior to those in new neighborhoods. Most social environment factors in new neighborhoods achieved higher satisfaction levels than those in old neighborhoods. The satisfaction levels of aging-friendly community factors in both old and new neighborhoods were below the expectation levels of elders.

Practical implications

In order to improve physical aging-friendly environments in old neighborhoods, it is suggested that full use is made of school facilities and the renovation of old buildings. The locations of public transportation stations in new neighborhoods are recommended to be revised within 5-min walking distances of senior residents. Both old and new neighborhoods are encouraged to improve social aging-friendly environments by increasing the coverage of medical services and creating multiple approaches to recreation activities.

Originality/value

These findings have empirical significance for urban planners and policy makers, in regard to identifying disparities between old and new neighborhoods, and understanding the equitable allocation and distribution of urban resources.

Details

Engineering, Construction and Architectural Management, vol. 26 no. 7
Type: Research Article
ISSN: 0969-9988

Keywords

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