Process capability and data contamination

DOI nefunkční (4.5.2018)Purpose: The paper centres on process capability and its relation to data contamination. Process capability may be distorted due to imprecise data. The paper analyses to what extent capability changes reflect problems in data so that the changes can be attributed to data sampling rather than the true performance of the process. This is important because it is usually much simpler to increase the precision of data sampling than the process itself. Methodology/Approach: The paper has two major parts. In part one, effect of data contamination on the observed process characteristic is analysed. The effect is analysed using data obtained from simulated random drawings and the chi-squared test. In the other part, reaction of capability to data contamination is observed. The capability is measured by a univariate capability index. Findings: Regarding the sensitivity of the index to contamination, it is different depending on the capability before the contamination. This leads to conclusions about when the company using the index should focus more on the way the data is measured, and when it should focus more on improving the process in question. The analysis shows that if the company is used to high levels of capability and records its drop, it is worth analysing its measurement system first, as the index is at higher levels more sensitive to data contamination. Research Limitation/implication: The study concerns a single univariate index, and the contamination is modelled with only several probability distributions. Originality/Value of paper: The findings are not difficult to detect, but are not known in practice where companies do not realize that problems with their process capability may sometimes lie in the data they use and not in the process itself.Web of Science213615

Desirability to characterize process capability

Over the past few years continuously new process capability indices have been developed, most of them with the aim to add some feature missed in former process capability indices. Thus, for nearly any thinkable situation now a special index exists which makes choosing a certain index as difficult as interpreting and comparing index values correctly. In this paper we propose the use of the expected value of a certain type of function, the so-called desirability function, to assess the capability of a process. The resulting index may be used analogously to the classical indices related to Cp, but can be adapted to nearly any process and any specification. It even allows a comparison between different processes regardless of their distribution and may be extended straightforwardly to multivariate scenarios. Furthermore, its properties compare favorably to the properties of the ?classical? indices. --

Identifying higher capability maturity KPAs of construction organisations; Model refinement through expert interviews

Process improvement has been identified as a mechanism of achieving the much needed performance improvements within the construction industry. Despite the concerns of being an industry with unique characteristics, construction has borrowed some process improvement principles from other industries such as software. However, while process capability maturity has been identified as an important aspect of process improvements in many disciplines construction shows a clear research gap in that area. Among the few capability maturity based process improvement initiatives within the construction industry, there is a clear necessity to investigate what are the higher capability maturity level dynamics of construction process improvements. Addressing this requirement, this paper discusses a model to identify construction higher capability maturity

Knowledge sharing capability, absorptive capacity, and innovation capability: an empirical study of Indonesia's information and communication technology industry

This research investigates the relationships between knowledge sharing capability, absorptive capacity, and innovation capability. This research proposed and tested three hypotheses. The data was collected by conducting a survey on 114 companies of Indonesia’s information and communication technology industry, including a telecommunication service provider, a support service provider,network vendors, and consumer devices vendors. This study finds that absorptive capacity is the intervening factor between knowledge sharing capability and innovation capability. It also shows that potential absorptive capacity has a positive influence on realized absorptive capacity, and realized absorptive capacity has a positive influence on product and process innovation capability

Acceptance sampling plan for multiple manufacturing lines using EWMA process capability index

The problem of developing a product acceptance determination procedure for multiple characteristics has attracted the quality assurance practitioners. Due to sufficient demands of consumers, it may not be possible to deliver the quantity ordered on time using the process based on one manufacturing line. So, in factories, product is manufactured using multiple manufacturing lines and combine it. In this manuscript, we present the designing of an acceptance sampling plan for products from multiple independent manufacturing lines using exponentially weighted moving average (EWMA) statistic of the process capability index. The plan parameters such as the sample size and the acceptance number will be determined by satisfying both the producer's and the consumer's risks. The efficiency of the proposed plan will be discussed over the existing sampling plan. The tables are given for industrial use and explained with the help of industrial examples. We conclude that the use of the proposed plan in these industries minimizes the cost and time of inspection. Smaller the sample size means low inspection cost. The proposed plan for some non-normal distributions can be extended as a future research. The determination of sampling plan using cost model is also interested area for the future research. ? 2017 The Japan Society of Mechanical Engineers.11Ysciescopu

Possibilities of using graphical and numerical tools in the exposition of process capability assessment techniques

Purpose: The paper focuses on how the problem of process capability assessment can be handled when taught, using convenient numerical and graphical means. The contents of the paper results from the authors' own academic and practical experience, which suggested that many important steps are overlooked in the process of selecting and using capability indices. Methodology/Approach: Selected problems in capability assessment are illustrated with suitable examples and graphs. Findings: The authors' experience is reflected in the paper, aiming to emphasize what matters and how, and what does not. Also, a new capability index is introduced. Research Limitation/implication: The style in which the problems are analysed may serve as a guide for further studies in the field and capability index applications. Originality/Value of paper: The paper also contains, aside from specific examples, some more advanced techniques, and is therefore accompanied by software readouts, since computer support is required in such cases. Category: Conceptual paperWeb of Science232331