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Article
Publication date: 1 July 2006

Chongbin Zhao, T. Nishiyama and A. Murakami

The main purpose of this paper is to present and use the particle simulation method to explicitly simulate the spontaneous crack initiation phenomenon in brittle materials, and to…

532

Abstract

Purpose

The main purpose of this paper is to present and use the particle simulation method to explicitly simulate the spontaneous crack initiation phenomenon in brittle materials, and to compare the particle simulation results with experimental ones on the laboratory scale.

Design/methodology/approach

Using the particle simulation method, the brittle material is simulated as an assembly of particles so that the microscopic mechanism of inter‐ and intra‐particle crack initiation can be straightforwardly considered on the microscopic scale. A laboratory test has been conducted using a gypsum sample model to validate the particle simulation method for explicitly simulating the spontaneous crack initiation phenomenon.

Findings

The paper finds that in terms of simulating the macroscopic sliding surface along or around the contact plane between a block and its foundation, both the laboratory test and the particle simulation have produced consistent results. This indicated that the particle simulation method is capable of simulating macroscopic cracks through simulating conglomerations and accumulations of microscopic crack initiation within the brittle material. Compared with other numerical methods, the particle simulation method is more suitable for explicitly and effectively simulating spontaneous crack initiation problems on the microscopic scale in brittle materials.

Originality/value

The particle simulation method can be used to explicitly and effectively simulate the spontaneous crack initiation on the microscopic scale in brittle materials. It can be also used to simulate the macroscopic sliding surface along or around the contact plane between a block and its foundation. The experimental results of simulating the spontaneous crack initiation on the laboratory scale in brittle materials are very valuable for validating the numerical simulation results obtained not only from the particle simulation method, but also from other numerical simulation methods.

Details

Engineering Computations, vol. 23 no. 5
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 7 April 2015

Mustafa Kumral

The purpose of this paper is to provide a decision-making tool on where to send mining parcels extracted in such a way as to minimize losses arising from mis-classification. The…

428

Abstract

Purpose

The purpose of this paper is to provide a decision-making tool on where to send mining parcels extracted in such a way as to minimize losses arising from mis-classification. The problem is complicated because actual values of mining parcels cannot be known and the decision is made on the basis of the estimation/simulations of the parcels generated from sparse data.

Design/methodology/approach

The loss minimization associated with mis-classification is formulated as a non-linear optimization problem and solved by successive mixed integer programming. By assigning reasonable values to some variables making problem non-linear, the problem is converted to a mixed integer programming (MIP) and is solved by a standard MIP optimization engine.

Findings

A case study was conducted to see the performance of the proposed approach on a deposit with gold and silver variables. The proposed approach was also compared with conventional grade control approaches. The results showed that the approach proposed could be used for solving grade quality control problem.

Practical implications

Grade quality control problem is well-known problem and there is no effective solution approach. This paper proposes to solve the problem through standard operation research software. As such, mine planner and engineers have a means to deal with grade quality problem in mining operations.

Originality/value

The paper formulates multi-variable grade quality control problem as an optimization problem on the contrary to previous one-shot approaches. This can increase profit and operation efficiency. The research also use target grades rather than cut-off grade posing problems in mining operations.

Details

International Journal of Quality & Reliability Management, vol. 32 no. 4
Type: Research Article
ISSN: 0265-671X

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Book part
Publication date: 24 March 2015

Abstract

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The Broad Autism Phenotype
Type: Book
ISBN: 978-1-78441-657-7

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Article
Publication date: 16 September 2021

Yipeng Zhu, Tao Wang and Shiqiang Zhu

This paper aims to develop a robust person tracking method for human following robots. The tracking system adopts the multimodal fusion results of millimeter wave (MMW) radars and…

336

Abstract

Purpose

This paper aims to develop a robust person tracking method for human following robots. The tracking system adopts the multimodal fusion results of millimeter wave (MMW) radars and monocular cameras for perception. A prototype of human following robot is developed and evaluated by using the proposed tracking system.

Design/methodology/approach

Limited by angular resolution, point clouds from MMW radars are too sparse to form features for human detection. Monocular cameras can provide semantic information for objects in view, but cannot provide spatial locations. Considering the complementarity of the two sensors, a sensor fusion algorithm based on multimodal data combination is proposed to identify and localize the target person under challenging conditions. In addition, a closed-loop controller is designed for the robot to follow the target person with expected distance.

Findings

A series of experiments under different circumstances are carried out to validate the fusion-based tracking method. Experimental results show that the average tracking errors are around 0.1 m. It is also found that the robot can handle different situations and overcome short-term interference, continually track and follow the target person.

Originality/value

This paper proposed a robust tracking system with the fusion of MMW radars and cameras. Interference such as occlusion and overlapping are well handled with the help of the velocity information from the radars. Compared to other state-of-the-art plans, the sensor fusion method is cost-effective and requires no additional tags with people. Its stable performance shows good application prospects in human following robots.

Details

Industrial Robot: the international journal of robotics research and application, vol. 49 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 8 February 2013

Myagmarbayar Nergui, Yuki Yoshida, Nevrez Imamoglu, Jose Gonzalez, Masashi Sekine and Wenwei Yu

The aim of this paper is to develop autonomous mobile home healthcare robots, which are capable of observing patients’ motions, recognizing the patients’ behaviours based on…

1727

Abstract

Purpose

The aim of this paper is to develop autonomous mobile home healthcare robots, which are capable of observing patients’ motions, recognizing the patients’ behaviours based on observation data, and providing automatically calling for medical personnel in emergency situations. The robots to be developed will bring about cost‐effective, safe and easier at‐home rehabilitation to most motor‐function impaired patients (MIPs).

Design/methodology/approach

The paper has developed following programs/control algorithms: control algorithms for a mobile robot to track and follow human motions, to measure human joint trajectories, and to calculate angles of lower limb joints; and algorithms for recognizing human gait behaviours based on the calculated joints angle data.

Findings

A Hidden Markov Model (HMM) based human gait behaviour recognition taking lower limb joint angles and body angle as input was proposed. The proposed HMM based gait behaviour recognition is compared with the Nearest Neighbour (NN) classification methods. Experimental results showed that a human gait behaviour recognition using HMM can be achieved from the lower limb joint trajectory with higher accuracy than compared classification methods.

Originality/value

The research addresses human motion tracking and recognition by a mobile robot. Human gait behaviour recognition is HMM based lower limb joints and body angle data from extracted from kinect sensor at the mobile robot.

Details

International Journal of Intelligent Unmanned Systems, vol. 1 no. 1
Type: Research Article
ISSN: 2049-6427

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Book part
Publication date: 14 October 2019

Alfred Ogle and David Lamb

Purpose: An examination of the uptake and application of Robotic, Artificial Intelligence and Service Automation (RAISA) technologies by the events industry…

Abstract

Purpose: An examination of the uptake and application of Robotic, Artificial Intelligence and Service Automation (RAISA) technologies by the events industry.

Design/methodology/approach: Academic and practitioner literature review and analysis pertaining to the relevance of RAISA in events.

Findings: The events industry has tended to rely on automation in staging and event production and the application of RAISA in events has been limited but holds great potential for the future. Whereas, in the hospitality and tourism industries RAISA has been applied across a range of service functions. For example, in such industries, artificial intelligence, machine learning and service robotics technologies have become commonplace. Nonetheless, the same level of adoption of RAISA in events is less evident particularly in front-of-house operation, due largely to the incompatibility with the raison d'être of event attendance – the purposive congregation of people seeking an event experience.

Research limitations/implications: The findings are the views of the authors and are therefore reliant upon existing events management literature on RAISA and their interpretation of this information and its application to the events industry.

Practical implications: RAISA has the capacity to play a crucial technical function in the events industry. However, it needs to be acknowledged that an event is essentially an experiential product which is simultaneously delivered and consumed in a particular setting/venue. RAISA applications and techniques avail event management immense sustainability and growth potential.

Social implications: Events are expressions of human social interactions and activities. Given the recent trend in sports media consumption as a substitute for live event attendance compounded by barriers to event attendance such as heightened terrorism threat and high expense/cost, there is a real risk of degradation of the social significance of the events industry. The prudent uptake of RAISA has the potential to emolliate the barriers to attendance while facilitating effective marketing and industry sustainability.

Originality/value: This chapter provides a new perspective in focusing on the potential applicability of RAISA in event management practice.

Details

Robots, Artificial Intelligence, and Service Automation in Travel, Tourism and Hospitality
Type: Book
ISBN: 978-1-78756-688-0

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Article
Publication date: 29 April 2014

Seok-Hwan Huh, Kang-Dong Kim and Keun-Soo Kim

The purpose of this paper is to evaluate the relationship between the Cu trace and epoxy resin and to check the validity of surface and interfacial cutting analysis system…

200

Abstract

Purpose

The purpose of this paper is to evaluate the relationship between the Cu trace and epoxy resin and to check the validity of surface and interfacial cutting analysis system (SAICAS) by comparing its results to those of the 90° peel test.

Design/methodology/approach

In this study, the effects of surface morphology on the adhesion strength were studied for a Cu/epoxy resin system using a SAICAS. In order to evaluate the peel strength of the sample, the curing degree and surface morphology of the epoxy resin were varied in the Cu/epoxy resin system.

Findings

The results indicated that the peel strength is strongly affected by the curing degree and the surface morphology of the epoxy layer. As the pre-cure time increased, the interactions between the epoxy resin and permanganate during the adhesion promotion process decreased, which decreased the surface roughness (Ra) of the resin. Therefore, the surface roughness of the epoxy resin decreased with increasing pre-cure time. The curing degree was calculated with the FTIR absorption peak (910 cm−1) of the epoxy groups. The high curing degree for the epoxy resin results in a coral-like morphology that provides a better anchoring effect for the Cu trace and a higher interfacial strength.

Research limitations/implications

It is necessary to study the further adhesion strength, i.e. the friction energy, the plastic deformation energy, and the interfacial fracture energy, in micro- and nanoscale areas using SAICAS owing to insufficient data regarding the effects of size and electroplating materials.

Originality/value

From findings, it is found that measuring the peel strength using SAICAS is particularly useful because it makes the assessment of the peel strength in the Cu/epoxy resin system of electronic packages possible.

Details

Circuit World, vol. 40 no. 2
Type: Research Article
ISSN: 0305-6120

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Article
Publication date: 20 December 2024

Frank Ferdik, George Froggé, Mikaela Cooney and Hayden P. Smith

Public willingness to obey the law is partially determined by their satisfaction levels with police job performance. Although numerous studies have researched determinants of…

4

Abstract

Purpose

Public willingness to obey the law is partially determined by their satisfaction levels with police job performance. Although numerous studies have researched determinants of citizen satisfaction with the police, to date, none have examined whether political orientations, measured according to voting preferences, share any association with this outcome. No study, moreover, has analyzed if the effects of political orientations vary by contact with law enforcement.

Design/methodology/approach

Questionnaire data were collected from a convenience sample of university students to determine whether the effects of political orientations on satisfaction with law enforcement varied by contact with the police.

Findings

Among the total sample, as well as those who had no prior contact with the police, liberal respondents expressed less satisfaction with law enforcers when compared to conservatives. Among those who were either contacted by the police, or who initiated contact, political orientations had no effect on satisfaction. What was significant across all models though was procedural justice.

Research limitations

Generalization attempts are hindered considering the non-probability nature of the sample, while causality can also not be confirmed since data are cross-sectional.

Practical implications

Police officers must behave in procedurally fair manners when interacting with citizens and engage in community outreach initiatives in order to improve their image across society.

Originality/value

Findings offer insight into the conditions under which voting preferences can shape evaluations of the police.

Details

Policing: An International Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1363-951X

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Article
Publication date: 1 June 2001

Nobukaza Azuma and John Fernie

The aim of this paper is to develop an understanding of the retail marketing, merchandising, and logistical practices in the Japanese grocery supermarket sector. Most of the…

7540

Abstract

The aim of this paper is to develop an understanding of the retail marketing, merchandising, and logistical practices in the Japanese grocery supermarket sector. Most of the literature in English has focused on the structure of the sector with little detailed research on the Japanese consumer and the corporate response to retail change. This paper highlights the case of Summit Inc., which has established a niche position in the Japanese grocery market through its operational excellence.

Details

International Journal of Retail & Distribution Management, vol. 29 no. 6
Type: Research Article
ISSN: 0959-0552

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Book part
Publication date: 20 June 2003

Christopher W Anderson, Terry L Campbell, Narayanan Jayaraman and Gershon N Mandelker

An inverse relation between performance and managerial turnover at Japanese firms suggests that bank monitoring substitutes for other governance mechanisms (Kaplan, 1994; Kang &…

Abstract

An inverse relation between performance and managerial turnover at Japanese firms suggests that bank monitoring substitutes for other governance mechanisms (Kaplan, 1994; Kang & Shivdasani, 1995). Morck and Nakamura (1999), however, report that Japanese banks protect their self-interests as creditors rather than the interests of shareholders when appointing corporate directors. We re-examine data on top management changes at Japanese firms and find results consistent with this latter notion. Specifically, management turnover is conditionally related to a firm’s ability to meet its short-term obligations rather than profitability or stock returns. Bank monitoring is therefore not a substitute for mechanisms that directly serve shareholders’ interests.

Details

Advances in Financial Economics
Type: Book
ISBN: 978-1-84950-214-6

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