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Article
Publication date: 15 May 2009

A. Omran, A. Kassem, G. El‐Bayoumi and M. Bayoumi

The purpose of this paper is to show the merit of using mission information in tuning the controller gains for Stewart manipulator instead of the generic inputs previously…

498

Abstract

Purpose

The purpose of this paper is to show the merit of using mission information in tuning the controller gains for Stewart manipulator instead of the generic inputs previously developed in literature.

Design/methodology/approach

The paper introduces two optimization techniques based on mission information. The first technique, a partial‐information technique, uses gain scheduling that applies different controllers for different mission tracks. The second technique, a full‐information technique uses a single robust controller by considering the full mission data. For demonstrating these techniques' feasibility, a nonlinear numerical simulation for a Stewart manipulator was built and tested using a generic mission. This mission consists of two piecewise trajectories (tracks). The proposed techniques were compared with one of the previous optimization techniques in literature, no‐information technique, in which a step response is used to search for optimal controller gains without any information about the mission. Genetic algorithms were used to search for the optimal controller gain in each case with different cost functions.

Findings

Based on the numerical simulations, the proposed mission‐based optimization techniques have superior performances compared with no‐information technique.

Research limitations/implications

The proposed techniques were applied in a joint space or for a decentralized control. The work can be extended to be applied in a task space or for a centralized control.

Originality/value

The paper proposes two novel optimization techniques: partial‐ and full‐information techniques for tuning the controller gains of a Stewart manipulator, where mission information was imbedded into the cost function. These two techniques are generally applicable for other nonlinear systems such as aircraft stability and control augmentation systems.

Details

Aircraft Engineering and Aerospace Technology, vol. 81 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 6 January 2012

Qiang Meng, Tao Zhang, Jingfeng He, Jingyan Song and Xuedong Chen

The precise control and dynamic analysis of the electrical Stewart platform have not been so well treated in the literature. This paper aims to design a novel model‐based…

550

Abstract

Purpose

The precise control and dynamic analysis of the electrical Stewart platform have not been so well treated in the literature. This paper aims to design a novel model‐based controller to improve the tracing performance of the electrical Stewart platform. Moreover, the simulations under uncertain environments are used to verify the robustness of the controller.

Design/methodology/approach

In the electrical Stewart platform, there exist two special movements of the motor systems: motor systems' movement with the actuators and meanwhile the rotors and snails' rotation around their axis. The Kane equation is used to compute the driven torque of the movements of motor systems, actuators and movable platform. The improved dynamic models of the electrical Stewart platform which consider the motor systems and actuators' influences are used to design the novel controller. The PID controller and the simple model‐based controller are also developed to compare with the novel one. Moreover, the robustness of the controller is verified by the platform friction and the parameters uncertainty.

Findings

Simulation results show that the novel model‐based controller can gain a better tracing performance than the PID controller and even the simple model‐based controller. Under the environments of the platform with friction and 5% parameters variety, the tracing performance of the novel controller is also satisfactory, which verifies the robustness of the controller. Most importantly, the novel model‐based controller can be used in a higher precision control demand and a more complicated environment.

Originality/value

The main contribution of this paper is to derive a novel model‐based controller considering the motor systems' influence, which enhances the robustness of the controller. To the authors' best knowledge, such a framework for the improved model based controller has not been well treated in the past literature. The conventional PID controller and a simple model‐based controller are also built to verify the advantages of the improved model‐based controller.

Details

Industrial Robot: An International Journal, vol. 39 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 14 November 2016

Islam El Bayoumi Salem and Nevenka Čavlek

The purpose of this study is twofold: it aims to examine hotel website features by conducting a content analysis and it analyses customers’ viewpoints about the importance of the…

2669

Abstract

Purpose

The purpose of this study is twofold: it aims to examine hotel website features by conducting a content analysis and it analyses customers’ viewpoints about the importance of the contents of hotel websites. The study involves a quantitative method of measurement and evaluation of the information provided by hotel websites. It tries to evaluate the richness of definite and ample information dimensions, which as a whole constitutes the information services offered through the website.

Design/methodology/approach

The study is based on two pillars: all five-star hotel chains (113 hotels) in Egypt as the population frame to evaluate the contents of their websites; and a sample of 406 customers selected to examine the customers’ views on the importance of the contents of hotel websites. This study proposes a quantitative evaluation frame of all dimensions provided by hotel websites which is developed, tested and validated.

Findings

The study has revealed important findings that can help hotel managers to adjust the information on the websites to be more efficient and customer-oriented.

Research limitations/implications

Because of the chosen research approach, the research results may lack generalizability. Therefore, researchers are encouraged to test the proposed frame again in further studies.

Practical implications

The study includes implications for the development of hotel website evaluation from the perspective of two sides, hotel managers and customers, by using a unique quantitative evaluation model.

Originality/value

This research has for the first time combined statements from the perspective of two sides – hotel managers and customers.

Details

Journal of Hospitality and Tourism Technology, vol. 7 no. 4
Type: Research Article
ISSN: 1757-9880

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Article
Publication date: 23 January 2009

Belinda T. Orzada, Mary Ann Moore, Billie J. Collier and Jonathan Yan Chen

The purpose of this paper is to investigate the effect of laundering on the drape, shear, and bending properties of bottom weight fabrics.

980

Abstract

Purpose

The purpose of this paper is to investigate the effect of laundering on the drape, shear, and bending properties of bottom weight fabrics.

Design/methodology/approach

Six bottom‐weight 100 percent cotton fabrics were included. Collier's Drape Tester was utilized to obtain drape values. Bending and shear values were measured on the KES‐F Shear Tester and the Pure Bending Tester. Three laundering cycles (unlaundered, one and five home launderings) following AATCC methods were explored.

Findings

Laundry cycle did not have a significant effect on fabric drape, shear or bending properties. However, drape values increased overall, while shear and bending modulus and hysteresis decreased, resulting in a more drapable, pliable fabric after five laundry cycles.

Research limitations/implications

Future research examining a wider variety of fabrics and conducting a greater number of laundry cycles to approximate an average yearly number of laundry cycles is recommended. An expansion of this preliminary study should give more conclusive evidence of the trends observed.

Originality/value

Objective measurement of drape and fabric mechanical properties related to drape after laundry treatments would assist the apparel manufacturer in developing laundry recommendations based on the fabric's performance and in selecting fabrics which maintain their drape characteristics, mechanical properties, and dimensional stability with use. Higher quality garments with increased consumer satisfaction would result.

Details

International Journal of Clothing Science and Technology, vol. 21 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

Available. Open Access. Open Access
Article
Publication date: 16 October 2018

Dalal Usamah Zaid Alkazemi and Asma Saleh

This paper aims to assess the consumption of dairy products in Kuwaiti children, and develop and validate a semi-quantitative food frequency questionnaire to measure dairy product…

2130

Abstract

Purpose

This paper aims to assess the consumption of dairy products in Kuwaiti children, and develop and validate a semi-quantitative food frequency questionnaire to measure dairy product consumption.

Design/methodology/approach

This cross-sectional study was based on a sample of child–parent dyads (n = 150). A dietary assessment questionnaire on local dairy products consumed by preschool and preadolescent children was developed. Serving and portion sizes were evaluated on the basis of the guidelines of the United States Department of Agriculture and the American Academy of Pediatrics to calculate median intake levels of three age groups (3-5, 6-8 and 9-11 years).

Findings

All children met or exceeded the recommended daily servings of dairy products for their age and sex. Dairy product intake was often from processed dairy including milk-based desserts, flavored milk and cheese. Compared to boys, girls consumed more yogurt (15.5 per cent vs 14.2 per cent, p = 0.001) and milk-based desserts (15.5 vs 14.3, p = 0.001). In boys, flavored milk contributed more to the total dairy intake than in girls, especially in 6-8-year-olds (21.8 per cent vs 18.9 per cent, p = 0.021). Weight status was not associated with dairy product intake in either sex.

Originality/value

This is the first study that quantifies dairy product consumption in Kuwaiti children and provides insight into sex-specific trends in dairy product selection. The findings of this study may help in investigating relationships between dairy product consumption in children and disease risk factors, and are important for the development of local dietary guidelines for children.

Details

Nutrition & Food Science, vol. 49 no. 1
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 26 April 2022

Elham Kariri and Kusum Yadav

In the final step, the trust model is applied to the on-demand federated multipath distance vector routing protocol (AOMDV) to introduce path trust as a foundation for routing…

95

Abstract

Purpose

In the final step, the trust model is applied to the on-demand federated multipath distance vector routing protocol (AOMDV) to introduce path trust as a foundation for routing selection in the route discovery phase, construct a trusted path, and implement a path warning mechanism to detect malicious nodes in the route maintenance phase, respectively.

Design/methodology/approach

A trust-based on-demand multipath distance vector routing protocol is being developed to address the problem of flying ad-hoc network being subjected to internal attacks and experiencing frequent connection interruptions. Following the construction of the node trust assessment model and the presentation of trust evaluation criteria, the data packet forwarding rate, trusted interaction degree and detection packet receipt rate are discussed. In the next step, the direct trust degree of the adaptive fuzzy trust aggregation network compute node is constructed. After then, rely on the indirect trust degree of neighbouring nodes to calculate the trust degree of the node in the network. Design a trust fluctuation penalty mechanism, as a second step, to defend against the switch attack in the trust model.

Findings

When compared to the lightweight trust-enhanced routing protocol (TEAOMDV), it significantly improves the data packet delivery rate and throughput of the network significantly.

Originality/value

Additionally, it reduces the amount of routing overhead and the average end-to-end delay.

Details

International Journal of Pervasive Computing and Communications, vol. 20 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

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Article
Publication date: 31 October 2008

Amna A.H. Rayes, Sabah M.M. El‐Naggar and Nayra Sh. Mehanna

The purpose of this paper is to evaluate the protective effect of natural fermented milk (NFM) against liver cancer.

705

Abstract

Purpose

The purpose of this paper is to evaluate the protective effect of natural fermented milk (NFM) against liver cancer.

Design/methodology/approach

Five types of NFM were collected from different places around Makka. The natural flora which present in them were studied and certain types which contain Lactobacillus spp. and Bifidobacterium spp. strains were selected to be used in the research. The nutritional experiment was carried out on 20 Albino mice divided into four groups. The first group (A) was control (not fed on NFM). The second (B) and third (C) groups were fed daily on (NFM) for two weeks. The final group (D) received basal diet only for four weeks, but after two weeks the third and fourth groups were treated orally by one dose of toxic mutagen (0.25 mg/mouse). The quality of life was measured by: specific strain count in stool; histopathological and histochemical studies on liver; and lymphocytic count.

Findings

Cow's milk which contains Lactobacillus spp. and Bifidobacterium spp. has a protective effect depending on its anti‐microbial properties. Also it enhances the endogenous intestinal probiotic bacteria that have several beneficial effects (i.e. detoxification and antigen toxicity) and stimulation of immune modulator cells.

Originality/value

The paper evaluates the protective effect of natural fermented milk (NFM) against cancer of the liver.

Details

Nutrition & Food Science, vol. 38 no. 6
Type: Research Article
ISSN: 0034-6659

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Article
Publication date: 22 August 2022

Ratnmala Nivrutti Bhimanpallewar, Sohail Imran Khan, K. Bhavana Raj, Kamal Gulati, Narinder Bhasin and Roop Raj

Federation analytics approaches are a present area of study that has already progressed beyond the analysis of metrics and counts. It is possible to acquire aggregated information…

58

Abstract

Purpose

Federation analytics approaches are a present area of study that has already progressed beyond the analysis of metrics and counts. It is possible to acquire aggregated information about on-device data by training machine learning models using federated learning techniques without any of the raw data ever having to leave the devices in the issue. Web browser forensics research has been focused on individual Web browsers or architectural analysis of specific log files rather than on broad topics. This paper aims to propose major tools used for Web browser analysis.

Design/methodology/approach

Each kind of Web browser has its own unique set of features. This allows the user to choose their preferred browsers or to check out many browsers at once. If a forensic examiner has access to just one Web browser's log files, he/she makes it difficult to determine which sites a person has visited. The agent must thus be capable of analyzing all currently available Web browsers on a single workstation and doing an integrated study of various Web browsers.

Findings

Federated learning has emerged as a training paradigm in such settings. Web browser forensics research in general has focused on certain browsers or the computational modeling of specific log files. Internet users engage in a wide range of activities using an internet browser, such as searching for information and sending e-mails.

Originality/value

It is also essential that the investigator have access to user activity when conducting an inquiry. This data, which may be used to assess information retrieval activities, is very critical. In this paper, the authors purposed a major tool used for Web browser analysis. This study's proposed algorithm is capable of protecting data privacy effectively in real-world experiments.

Details

International Journal of Pervasive Computing and Communications, vol. 21 no. 1
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 7 February 2025

Mohammad Masoud Nakhostin, Fariborz Jolai, Esmaeil Hadavandi and Mohammad Chavosh Nejad

The primary goal of this research is to introduce a data-driven Problem-Solving Approach for Performance Improvement in Healthcare Systems (DPAPIH). This approach combines process…

28

Abstract

Purpose

The primary goal of this research is to introduce a data-driven Problem-Solving Approach for Performance Improvement in Healthcare Systems (DPAPIH). This approach combines process mining and data mining techniques to enhance operational efficiency by identifying bottlenecks in Coronary Artery Bypass Grafting (CABG) procedures, particularly focusing on variability in Length of Stay (LOS) in the Intensive Care Unit (ICU). The study, implemented at Tehran Heart Center, aims to optimize patient flow, reduce ICU congestion and improve hospital efficiency by predicting and managing the occurrence of postoperative Atrial Fibrillation (AF), a significant cause of prolonged ICU stays.

Design/methodology/approach

The study introduces a data-driven problem-solving approach that integrates process mining and data mining techniques to improve performance in healthcare systems. Focusing on coronary artery bypass grafting (CABG) at Tehran Heart Center, the approach identifies bottlenecks, particularly variability in ICU length of stay (LOS) and predicts postoperative atrial fibrillation (AF). A mixed-methods approach is employed, combining quantitative process mining analyses with qualitative insights from expert consultations. The CHAID decision tree algorithm, alongside other models, is used to predict AF, enabling preemptive interventions, improving patient flow and optimizing resource allocation to reduce hospital congestion and costs.

Findings

The study reveals that postoperative Atrial Fibrillation (AF) significantly increases the length of stay (LOS) in the Intensive Care Unit (ICU), creating bottlenecks that delay subsequent surgeries and elevate hospital costs. A predictive model developed using CHAID decision tree algorithms achieved a prediction accuracy of 71.4%, allowing healthcare providers to anticipate AF occurrences. This capability enables proactive measures to reduce ICU congestion, improve patient flow and optimize resource allocation. The findings emphasize the importance of AF management in enhancing operational efficiency and improving patient outcomes in Coronary Artery Bypass Grafting (CABG) procedures.

Originality/value

This study presents an innovative integration of fuzzy process mining and data mining algorithms to address performance bottlenecks in healthcare systems, specifically within the coronary artery bypass surgery process. By identifying atrial fibrillation as a key factor in length of stay fluctuations and developing a robust predictive model, the research offers a novel, data-driven approach to performance improvement. The implementation at Tehran Heart Center validates the model’s practical applicability, demonstrating significant potential for enhancing patient outcomes, optimizing resource allocation and informing decision-making in healthcare management.

Details

Business Process Management Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1463-7154

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Article
Publication date: 1 April 2014

Shalini Ramdas Lihitkar and R.S. Lihitkar

The purpose of this paper is to know the institutions who are developing electronic theses and dissertations (ETDs) in India, and to compare the ETDs in India based on a…

573

Abstract

Purpose

The purpose of this paper is to know the institutions who are developing electronic theses and dissertations (ETDs) in India, and to compare the ETDs in India based on a predetermined parameter.

Design/methodology/approach

The methodology used for this research paper was a descriptive method. The institutional web sites were browsed and searched to collect the data. A relevant literature review was also carried out to describe the current status and other relevant information.

Findings

Institutional repositories are a concept gaining movement today. India is moving ahead in this direction and major education and research institutes have already created their own institutional repositories. In analysis and findings, a detailed report of the analysis of data collection and its subsequent interpretations are given.

Practical implications

If anybody would like to develop ETDs they can this overview of all the previous developed ETDs in India. It will be helpful for planning, developing and implementing new ETDs.

Originality/value

This type of research study has not made till now. It is very important to study current and different types of ETD projects in India and its status. The study of special subject repositories is important for the students, scholars and researchers as well as for the LIS professionals.

Details

Library Hi Tech News, vol. 31 no. 2
Type: Research Article
ISSN: 0741-9058

Keywords

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