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1 – 10 of over 31000
Article
Publication date: 12 October 2015

M. P. Jenarthanan, A Ram Prakash and R Jeyapaul

The purpose of this paper is to develop a mathematical model for optimizing the metal removal rate (MRR) through Response Surface Methodology (RSM). The developed model…

Abstract

Purpose

The purpose of this paper is to develop a mathematical model for optimizing the metal removal rate (MRR) through Response Surface Methodology (RSM). The developed model helps us to analyze the influence of individual input machining parameters (cutting speed, feed rate, weight percentage) on the responses in machining of Al-TiB2 composite.

Design/methodology/approach

RSM is used to optimize the MRR by developing a mathematical model. Three factors, three-level box Behnken design matrix in RSM is employed to carry out the experimental investigation. The “Design Expert 8.0” software is used for regression and graphical analysis of the data are collected. The optimum values of the selected variables are obtained by solving the regression equation and by analyzing the response surface contour plots. Analysis of variance (ANOVA) is applied to check the validity of the model and for finding the significant parameters.

Findings

The response surface model developed, helps to calculate the MRR at different input cutting parameters with the chosen range with more than 95 per cent confidence intervals.

Originality/value

The effect of machining parameters on MRR during machining of Al-TiB2 composites using RSM has not been previously analyzed.

Details

Multidiscipline Modeling in Materials and Structures, vol. 11 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 January 1991

Stuart S. Nagel

Scarce resources can be allocated to budget categories byprocessing a set of goals to be achieved, alternative budget categoriesand relations between each budget category…

Abstract

Scarce resources can be allocated to budget categories by processing a set of goals to be achieved, alternative budget categories and relations between each budget category and each goal expressed in whatever terms with which the user is comfortable. A concrete example is given involving the allocating of a $500,000 budget to the police and the courts in the light of the goals of crime reduction and fair procedure in separating the innocent from the guilty. The police do better than the courts on crime reduction, but the courts do better than the police on fair procedure. Fair procedure, it is suggested, is considered more important than crime reduction. With that tentative assumption one can determine what proportion of the budget should be allocated to the police and what proportion to the courts. Initial allocations may be changed in the light of whatever constraints exist concerning minimum amounts that need to be allocated to the police or the courts. The initial allocations can also be subjected to a sensitivity analysis, to see how responsive they are to changes in the inputs concerning the relative importance of the goals and the nature of the relationships between each budget category and each goal.

Details

International Journal of Public Sector Management, vol. 4 no. 1
Type: Research Article
ISSN: 0951-3558

Keywords

Article
Publication date: 1 April 1996

ALEXANDER M. ROBERTSON and PETER WILLETT

This paper describes the development of a genetic algorithm (GA) for the assignment of weights to query terms in a ranked‐output document retrieval system. The GA involves…

Abstract

This paper describes the development of a genetic algorithm (GA) for the assignment of weights to query terms in a ranked‐output document retrieval system. The GA involves a fitness function that is based on full relevance information, and the rankings resulting from the use of these weights are compared with the Robertson‐Sparck Jones F4 retrospective relevance weight. Extended experiments with seven document test collections show that the ga can often find weights that are slightly superior to those produced by the deterministic weighting scheme. That said, there are many cases where the two approaches give the same results, and a few cases where the F4 weights are superior to the ga weights. Since the ga has been designed to identify weights yielding the best possible level of retrospective performance, these results indicate that the F4 weights provide an excellent and practicable alternative. Evidence is presented to suggest that negative weights may play an important role in retrospective relevance weighting.

Details

Journal of Documentation, vol. 52 no. 4
Type: Research Article
ISSN: 0022-0418

Article
Publication date: 13 March 2017

Sue Teng Tew, Jan Mei Soon, Soottawat Benjakul, Thummanoon Prodran, Manee Vittayanont and Phakawat Tongnuanchan

Protein-based films have good barrier characteristics against gas compared to synthetic films, but they have poor mechanical properties and high water vapour permeability…

Abstract

Purpose

Protein-based films have good barrier characteristics against gas compared to synthetic films, but they have poor mechanical properties and high water vapour permeability (WVP) due to their hydrophilic nature. Sugarcane bagasse (SCB) is available abundantly in Southeast Asian countries and can be potentially utilized for its cellulose to increase the stiffness of the film. Hence, the purpose of this study was to develop a gelatine-based film from chicken feet incorporated with SCB.

Design/methodology/approach

Film-forming solutions (FFS) from chicken feet gelatine with different percentages of glycerol (25 and 35 per cent) were prepared by casting 4.0 g of FFS onto a rimmed silicone resin plate (50 × 50 mm2). Cellulose from SCB was purified and used to prepare hydrolyzed SCB. Films with 35 per cent glycerol were selected to be incorporated with different weight percentages (2.5, 5.0, 7.5 and 10.0 per cent) of hydrolyzed SCB to increase the tensile strength (TS) and lower the WVP of the films. Mechanical properties, colour and transparency of the films were also tested.

Findings

Films containing 35 per cent glycerol have lower TS but higher elongation at break compared to films prepared with 25 per cent glycerol. There were no significant differences between the films with 25 per cent and 35 per cent glycerol in thickness, WVP and transparency value tests. Film incorporated with 5.0 Wt.% SCB had a slight increment in TS (23.07 MPa) compared to the control film (22.50 MPa). WVP was also lowered from 2.18 × 10−11gm−1s−1Pa−1 to 1.85 × 10−11gm−1s−1Pa−1. The other properties, namely, thickness, colour measurement and transparency value, were significantly different (p < 0.05) but nearer to the properties of the control film.

Originality/value

This study incorporates hydrolyzed SCB to study the potential mechanical benefits in protein-based bio-films. There is potential to utilize agricultural waste (chicken feet and SCB) to develop food packaging films.

Details

Nutrition & Food Science, vol. 47 no. 2
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 1 March 1966

John F. Coplin

A review of some of the progress made in lift jet installations is presented in this paper. At the heart of it all is the low cost lightweight RB162 second generation lift…

Abstract

A review of some of the progress made in lift jet installations is presented in this paper. At the heart of it all is the low cost lightweight RB162 second generation lift jet which is simple and makes extensive use of glass reinforced plastics. Examples of plastic components are shown. The higher thrust/weight and thrust/volume ratio of a third generation lift jet are revealed. The weight of installed features is of comparable importance to the weight of the basic engine. Installed weight has been reduced over three lift jet generations, more than keeping pace with the improvements in basic engine thrust/weight ratio. Weight breakdowns are given for the V.T.O.L. equipment in a fighter‐type aircraft representative of all three generations. Progress on lift intake and exhaust jet deflectors is shown with reference to specific examples. Ground erosion is briefly discussed and shown to be greatly reduced by multiple nozzles and the rolling take‐off technique. Progress being made on some of the problems associated with installing eight lift jets in a V.T.O.L. strike aircraft is briefly discussed with reference to maintenance and instrumentation.

Details

Aircraft Engineering and Aerospace Technology, vol. 38 no. 3
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 25 July 2019

Tritos Laosirihongthong, Premaratne Samaranayake and Sev Nagalingam

The purpose of this paper is to propose a holistic approach for supplier evaluation and purchasing order allocation among the ranked suppliers who meet acceptable levels…

1473

Abstract

Purpose

The purpose of this paper is to propose a holistic approach for supplier evaluation and purchasing order allocation among the ranked suppliers who meet acceptable levels of economic, environmental and social measures.

Design/methodology/approach

A mixed research method of case study and analytical approach is adopted in this research. A fuzzy analytical hierarchical process (FAHP) is applied for ranking of suppliers. Supplier ranks are validated using judgements from multiple decision makers. Purchasing order allocation among the ranked suppliers is determined using cost minimization subject to multiple criteria of economic, environmental and social conditions. A cement manufacturing case example demonstrates and validates the proposed approach.

Findings

The research shows that both economic and environmental considerations are significant when suppliers are evaluated for sustainable procurement within the best practice of supply management process. Ranking of suppliers, based on experts’ opinions, indicates varying degrees of importance for each criterion. Adoption of sustainable procurement criteria for evaluating supplier in a cement manufacturing organization is explained by three organizational theories including resource-based, institutional and dynamic capabilities theories. Preferred suppliers from FAHP method are confirmed by judgements from multiple decision-makers. The analysis reveals that purchasing order allocation is different when suppliers are evaluated based on their relative importance and overall ranking.

Research limitations/implications

Currently, individual performance measures and decision-makers are selected from a limited set. The purchasing allocation among ranked suppliers, subjected to cost minimization, incorporates environmental objective of acceptable carbon dioxide emission and social perspective of health and safety of workers, and provides a new approach for dual supplier evaluation and purchasing allocation problem in cement industry. Adopting the proposed supplier evaluation and order allocation approach in practice needs to be guided by the operational principles and an overall methodology which is appropriate for the specific industry with sustainability objectives.

Practical implications

This research enables decision-makers to incorporate sustainability analysis in the supplier evaluation as the basis for best practice with an industry-friendly holistic approach. Using organizational theories, the research re-enforces the importance of not only the energy consumption and environmental management systems of environmental dimension as driving forces/factors from Institutional theory perspective, but also pollution controls and prevention as purchasing capabilities from resource-based theory perspective. The proposed approach is expected to motivate decision-makers to consider sustainable perspectives in supplier evaluation and order allocation processes in a global supply chain and can become a benchmarking tool.

Social implications

Suppliers’ information on health and safety of their truck drivers are used in order allocation, thus emphasizing the importance of social dimension and encouraging better conditions and benchmarking for delivery drivers.

Originality/value

This paper extends the contribution to the literature by providing guidelines for managers to set strategies, benchmarks and policies within broader sustainable supply chain practices and demonstrates the applicability of the approach using a cement-manufacturing scenario in an emerging economy.

Book part
Publication date: 4 September 2017

Barbara A. Haley and Aref N. Dajani

This research examines the effects of health, location, and other factors on receipt of wage income for young heads of households, aged 19 to 25, who lived in HUD-assisted…

Abstract

Purpose

This research examines the effects of health, location, and other factors on receipt of wage income for young heads of households, aged 19 to 25, who lived in HUD-assisted housing and in other rental housing in 2011.

Methodology/approach

This chapter reports results of analyses of the 2011 American Housing Survey, merged with HUD administrative records, available as a public-use file at the U.S. Census Bureau.

Findings

Nineteen percent of young householders in assisted housing and 8% in other rental housing reported less than good health or a disability. Nearly two-thirds of young householders in assisted housing reported receipt of earned income. For respondents in assisted housing who reported good health and no disabilities, logistic regression models suggest that educational attainment beyond a high school diploma, more than one adult in the household, and living in metropolitan areas in the Midwest or West census regions were positively and statistically significant for receipt of earned income. For respondents in both assisted and other rental housing who reported less than good health and/or disabilities, residence in assisted housing or educational attainment beyond a high school diploma were positively associated with receipt of earned income, while residence in the metropolitan South lowered the odds of receipt of earned income.

Social implications

Success of self-sufficiency programs will depend on accommodating the imperatives created by health, disability, and structural impediments created by a market economy.

Originality/value

This is the first analysis of health/disability and other barriers to paid employment that accurately identifies a nationally representative sample of young Millennials in HUD-assisted and other rental housing.

Details

Factors in Studying Employment for Persons with Disability
Type: Book
ISBN: 978-1-78714-606-8

Keywords

Article
Publication date: 19 July 2021

Lokanadham Dharmana and Venkata Subbaiah Kambagowni

This study aims to develop the Al-Si-Mg metal matrix composite, reinforced distinctly with lime stone powder (LSP; 12% by weight) and Al2O3 (12% by weight), and compare…

Abstract

Purpose

This study aims to develop the Al-Si-Mg metal matrix composite, reinforced distinctly with lime stone powder (LSP; 12% by weight) and Al2O3 (12% by weight), and compare their mechanical properties and tribological performance.

Design/methodology/approach

The composites are fabricated through stir casting process. In view of the previous work, the Al-LSP composite with LSP reinforcement (12 Wt.%) shows enhanced mechanical properties and tribological performance, as compared with other weight percentages.

Findings

Though the Al-LSP composite is less expensive, it shows similar hardness, tensile strength and specific strength, when compared with Al- Al2O3 composite. However, the Al-LSP composite exhibits significant enhancement of above three properties, when compared with Al-Si-Mg metal. The systematic factorial design of experiments is obtained through Taguchi OA [L9]. The tribological performance is estimated through wear rate (WR-mm3/m) and coefficient of friction (CF) by varying the operating parameters of sliding distance (SD), load (L) and sliding velocity (SV). According to ANOVA results, the optimal condition of WR for all the tested materials is L1SD3SV1. Further, the optimal condition of CF is L1SD1SV3 for Al-LSP and Al-Si-Mg metal, while L2SD3SV2 is for Al-Al2O3 composite. The regression equation predicts the measured experimental values within error band of ± 8 percentage.

Originality/value

A comparison of two composite materials (Al-LSP and Al-Al2O3) with same weight fractions (12%) shows almost same trend in both the mechanical and tribological testing process. However, the developed Al-LSP composite exhibited better properties than the Al-Al2O3 and Al-base. Therefore, Al-LSP can be suggested for automotive applications (i.e., connecting rod, cylinder liners, camshaft) and structural applications (such as frames, over hanging supports), without compromising in desirable original with properties of constituents in the new material, which is achievable for looking to the end uses.

Details

World Journal of Engineering, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 1 July 1949

F. Grinsted

THE importance of achieving a low structural weight is illustrated by simple estimates of the large decreases in aircraft gross weight and size made possible by…

Abstract

THE importance of achieving a low structural weight is illustrated by simple estimates of the large decreases in aircraft gross weight and size made possible by conscientious weight saving in structural design. A brief review is then made of the many variables in aircraft design which affect the weight of the structure. The review is made chiefly to emphasize the close interplay in project work between the structural and aerodynamic effects of changes of layout. Finally some remarks are made about comparative structural design efficiency. It is concluded that good weight prediction formulae are at present the best means by which the structural design efficiencies of different aircraft may be readily compared.

Details

Aircraft Engineering and Aerospace Technology, vol. 21 no. 7
Type: Research Article
ISSN: 0002-2667

Article
Publication date: 1 August 1998

Ranjita Misra and Laural Garzon

This paper evaluates the Nutrition Intervention Project (NIP) implemented statewide in the State of Virginia to determine the effectiveness of nutritional intervention in…

Abstract

This paper evaluates the Nutrition Intervention Project (NIP) implemented statewide in the State of Virginia to determine the effectiveness of nutritional intervention in decreasing pre‐term births and low birth weight (LBW) babies to at‐risk pregnant women in urban and rural areas. Sample size was 1,284. Majority of the respondents were white, primiparae, between 20‐29 years of age, and underweight (BMI < 19.8). Twenty‐one per cent of the of the births were pre‐term, and 13.3 per cent were in the LBW category. Regression analysis indicated that number of visits to the nutritionist was positively associated with birth weight and gestational age of the baby. Nutrition intervention (NI) decreased the smoking behaviour and improved the intake of iron supplements, both of which improved the weight gain and pregnancy outcomes. Effects analysis indicated that the causal effect operated both via intervening variables as well as directly between nutritional intervention and pregnancy outcomes. The path from NI to birth outcomes via weight gain was the strongest. Respondents in urban areas had a higher risk of pre‐term births than rural areas.

Details

Nutrition & Food Science, vol. 98 no. 4
Type: Research Article
ISSN: 0034-6659

Keywords

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