Use of a Quality Loss Function to Select Statistical Tolerances

1997 ◽  
Vol 119 (3) ◽  
pp. 410-416 ◽  
Author(s):  
H. Vasseur ◽  
T. R. Kurfess ◽  
J. Cagan
Keyword(s):  
Loss Function ◽  
A Priori ◽  
Manufacturing Cost ◽  
Quality Loss ◽  
Quality Loss Function ◽  
Component Assembly ◽  
The Impact ◽  
The Relationship ◽  
Selection Of

In this paper, we present a method for the selection of processes to manufacture various parts of an assembly by establishing a compromise between product quality and part manufacturing cost. We quantify the impact the precision of a part characteristic has on the overall quality of a product by using a standard Taguchi loss function. Part manufacturing cost is modeled as a function of process precision (i.e., standard deviation of the output characteristic) as opposed to previous models where manufacturing cost is a function of part tolerance. This approach is more realistic and does not assume, a priori, a relationship between conventional tolerance and process spread. Rather than allocating conventional tolerances on the assembly parts, we use statistical tolerances that are more pertinent when using a quality loss function. The model adopted makes it possible to investigate the relationship between optimum quality loss and tolerance variations. As expected, the optimum quality loss generally decreases when the tolerance increases. Exceptions may be encountered when changes of process occur. The manufacture of a simple three component assembly is studied to illustrate the findings.

Robust Tolerance Design With the Integer Programming Approach

1997 ◽  
Vol 119 (4A) ◽  
pp. 603-610 ◽  
Author(s):  
Chang-Xue (Jack) Feng ◽  
A. Kusiak
Keyword(s):  
Integer Programming ◽  
Loss Function ◽  
Programming Approach ◽  
Manufacturing Cost ◽  
Tolerance Design ◽  
Quality Loss ◽  
Quality Loss Function ◽  
The Cost ◽  
Manufacturing Yield ◽  
Selection Of

The quality loss function incorporates the cost of tolerances, however, it does not consider the manufacturing cost and design constraints. In this paper, a stochastic integer programming (SIP) approach is presented for simultaneous selection of tolerances and manufacturing processes. A direct link between the minimum manufacturing cost and the required level of manufacturing yield is established through the process capability index Cpk. As the tolerances in SIP are discrete, the solution generated is acceptable for manufacturing. It is shown that the integer programming models are applicable in the quality loss function and six sigma design approaches. The SIP approach is illustrated with a classical example of nonlinear tolerance design. The comparison of the proposed SIP approach, the Taguchi method, and the conventional mathematical models in tolerance synthesis is presented.

The Impact of Competitive Quasi-Market on Service Delivery in Benue State University, Makurdi Nigeria

GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 85-98
Author(s):  
Idoko Peter
Keyword(s):  
Service Delivery ◽  
A Priori ◽  
Least Square ◽  
Secondary Source ◽  
State University ◽  
Ordinary Least Square ◽  
Negative Effect ◽  
The Impact ◽  
The Relationship

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively

Examining the relationship between the price, the characteristics and the visitor evaluation of attributes of Italian farmhouses with an educational farm

2019 ◽  
Vol 75 (5) ◽  
pp. 827-839 ◽  
Author(s):  
Rosa Maria Fanelli
Keyword(s):  
A Priori ◽  
Principal Component ◽  
Online Reviews ◽  
Latent Factors ◽  
Content Type ◽  
Visitor Satisfaction ◽  
Main Determinants ◽  
The Impact ◽  
The Relationship

Purpose The purpose of this paper is to examine the relationship between the price charged for a guest room in a farmhouse with an educational farm, the farmhouse characteristics and the visitor evaluation of the principal external and internal farmhouse attributes. Design/methodology/approach A large sample of 10,880 visitor reviews, extrapolated from the websites of 399 Italian farmhouses with an educational farm (FEF), was analyzed. Principal component analysis (PCA) was performed to identify the main latent dimensions of the farmhouses (visitor satisfaction with farmhouse attributes, farmhouse dimensions, visitor frequency, farmhouse services, types of accommodation and altitude) that affect the price charged for a guest room. Subsequently, multivariate regression was applied to measure the impact of these new latent factors on the price. Findings Overall, the results indicate that the price of a farmhouse with an educational farm – in the context of this niche of the Italian agritourism sector – reflects the visitor evaluation of the farmhouse attributes (especially activities and facilities available in the surrounding countryside), the farmhouse dimensions, the types of accommodation, the number of services on offer and the presence of connectivity (WI-FI). In addition, the results reveal that the price represents an important driver that guides guests in their choice of a farmhouse and that it affects visitor satisfaction with farmhouse attributes. Research limitations/implications Because of the sample chosen, the data gathered are limited to one type of organization – Italian FEF. Furthermore, it may be important to investigate in more depth some issues that remain partly unanswered that concern this niche of the Italian agritourism sector. Practical implications Thanks to the identification of latent dimensions by PCA and the examination of their impact on the farmhouse price, farmhouse operators can understand a priori the main determinants on which to focus to improve the quality of activities and facilities available in the farmhouse location to better satisfy visitor expectations. Originality/value This study provides new and practical insights into the farmhouse experience in Italian municipalities, an area where very limited research has been conducted. Indeed, this is one of the few studies to focus on online reviews to evaluate more than two farmhouse attributes and their impact on pricing.

The Impact of Competitive Quasi-Market on Service Delivery in Benue State University, Makurdi Nigeria

GIS Business ◽  
2019 ◽  
Vol 14 (4) ◽  
pp. 53-66
Author(s):  
Idoko Peter
Keyword(s):  
Service Delivery ◽  
A Priori ◽  
Least Square ◽  
Secondary Source ◽  
State University ◽  
Ordinary Least Square ◽  
Negative Effect ◽  
The Impact ◽  
The Relationship

This research the impact of competitive quasi market on service delivery in Benue State University, Makurdi Nigeria. Both primary and secondary source of data and information were used for the study and questionnaire was used to extract information from the purposively selected respondents. The population for this study is one hundred and seventy three (173) administrative staff of Benue State University selected at random. The statistical tools employed was the classical ordinary least square (OLS) and the probability value of the estimates was used to tests hypotheses of the study. The result of the study indicates that a positive relationship exist between Competitive quasi marketing in Benue State University, Makurdi Nigeria (CQM) and Transparency in the service delivery (TRSP) and the relationship is statistically significant (p<0.05). Competitive quasi marketing (CQM) has a negative effect on Observe Competence in Benue State University, Makurdi Nigeria (OBCP) and the relationship is not statistically significant (p>0.05). Competitive quasi marketing (CQM) has a positive effect on Innovation in Benue State University, Makurdi Nigeria (INVO) and the relationship is statistically significant (p<0.05) and in line with a priori expectation. This means that a unit increases in Competitive quasi marketing (CQM) will result to a corresponding increase in innovation in Benue State University, Makurdi Nigeria (INVO) by a margin of 22.5%. It was concluded that government monopoly in the provision of certain types of services has greatly affected the quality of service experience in the institution. It was recommended among others that the stakeholders in the market has to be transparent so that the system will be productive to serve the society effectively

An ANP based selective assembly approach incorporating Taguchi’s quality loss function to improve quality of placements in technical institutions

2016 ◽  
Vol 28 (1) ◽  
pp. 112-131 ◽  
Author(s):  
Lalit Upadhayay ◽  
Prem Vrat
Keyword(s):  
Loss Function ◽  
Opportunity Cost ◽  
Technical Education ◽  
Selection Process ◽  
Total Loss ◽  
Quality Loss ◽  
Selective Assembly ◽  
Quality Loss Function ◽  
Content Type

Purpose – The performance of technical institutions in India is reflected through the level of campus placements. It is vital for them to have efficient, effective and robust placement policies. Selective assembly is a technique used in manufacturing industry in improving the quality of assemblies from relatively low-quality components. The purpose of this paper is to develop a methodology using selective assembly approach to improve the quality of placements of technical institutions in India. Design/methodology/approach – The paper presents a conceptual model for campus placement process by integrating Selective Assembly, Taguchi’s quality loss function (QLF) and analytic network process (ANP). The data used in the study was taken through surveys and expert opinions. In this paper, for “Selective Assembly” the terminology, “Selective Recruitment” has been used at appropriate places in the context of technical education. Findings – Selective matching of students’ skills done through ANP minimizes the total loss in terms of opportunity cost. Taguchi’s QLF concept was used to evaluate the total loss, in terms of opportunity cost, and to validate the superiority of selective assembly technique over the conventional selection process. Practical implications – The paper outlines measures that can help policy makers to successfully implement the suggested methodology to improve the quality of placements. Originality/value – The application of selective recruitment in the campus placement process is a unique feature in the area of technical education in India. The role of ANP in selective recruitment and assessment of the process through Taguchi’s QLF, illustrate the importance of integrated approach adopted in the selection process.

scholarly journals The Impact of Alkaloid-Producing Epichloë Endophyte on Forage Ryegrass Breeding: A New Zealand Perspective

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 158
Author(s):  
Colin Eady
Keyword(s):  
Seed Production ◽  
Health Issues ◽  
Abiotic Stressors ◽  
Livestock Health ◽  
The Right ◽  
The Impact ◽  
The Relationship ◽  
And Storage ◽  
Selection Of ◽  
Epichloë Endophyte

For 30 years, forage ryegrass breeding has known that the germplasm may contain a maternally inherited symbiotic Epichloë endophyte. These endophytes produce a suite of secondary alkaloid compounds, dependent upon strain. Many produce ergot and other alkaloids, which are associated with both insect deterrence and livestock health issues. The levels of alkaloids and other endophyte characteristics are influenced by strain, host germplasm, and environmental conditions. Some strains in the right host germplasm can confer an advantage over biotic and abiotic stressors, thus acting as a maternally inherited desirable ‘trait’. Through seed production, these mutualistic endophytes do not transmit into 100% of the crop seed and are less vigorous than the grass seed itself. This causes stability and longevity issues for seed production and storage should the ‘trait’ be desired in the germplasm. This makes understanding the precise nature of the relationship vitally important to the plant breeder. These Epichloë endophytes cannot be ‘bred’ in the conventional sense, as they are asexual. Instead, the breeder may modulate endophyte characteristics through selection of host germplasm, a sort of breeding by proxy. This article explores, from a forage seed company perspective, the issues that endophyte characteristics and breeding them by proxy have on ryegrass breeding, and outlines the methods used to assess the ‘trait’, and the application of these through the breeding, production, and deployment processes. Finally, this article investigates opportunities for enhancing the utilisation of alkaloid-producing endophytes within pastures, with a focus on balancing alkaloid levels to further enhance pest deterrence and improving livestock outcomes.

scholarly journals COVID-19 Pandemic and Quality of Life among Romanian Athletes

2021 ◽  
Vol 18 (8) ◽  
pp. 4065
Author(s):  
Germina-Alina Cosma ◽  
Alina Chiracu ◽  
Amalia Raluca Stepan ◽  
Marian Alexandru Cosma ◽  
Marian Costin Nanu ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Trait Anxiety ◽  
Negative Impact ◽  
Well Being ◽  
Quality Of Life Scale ◽  
Life Scale ◽  
Personality Item ◽  
The Impact ◽  
The Relationship

The aim of this study was to analyze athletes’ quality of life during the COVID-19 pandemic. The study involved 249 athletes between 15 and 35 of age, M = 21.22, SD = 5.12. The sample was composed of eight Olympic Games medalists, three European medalists, 67 international medalists, and 63 national medalists. The instruments used were: (1) COVID-19 Anxiety Scale, (2) Athlete Quality of Life Scale, (3) Impact of Pandemic on Athletes Questionnaire, and (4) International Personality Item Pool (IPIP Anxiety, Depression, and Vulnerability Scales). The results indicate significant differences in COVID-19 anxiety depending on the sport practiced, F (9239) = 3.81, p < 0.01, showing that there were significant differences between sports. The negative impact of the COVID-19 pandemic mediates the relationship between trait anxiety and the athletes’ quality of life. The percentage of mediation was 33.9%, and the indirect effect was −0.11, CI 95% (−0.18, −0.03), Z = −2.82, p < 0.01. Trait anxiety has an increasing effect on the intensity of the negative impact of the COVID-19 pandemic, 0.23, CI 95% (.10, 0.35), Z = 3.56, p < 0.01, and the negative impact of the COVID-19 pandemic has a decreasing effect on quality of life, −0.47, CI 95% (−0.67, −0.27), Z = −4.62, p < 0.01. Gender and age did not moderate the relationship between the negative impact of COVID-19 and athletes’ quality of life. The results of the study highlighted the impact that social isolation and quarantine have on athletes’ affective well-being.

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