Application of six sigma methodology to reduce defects of a grinding process

Six Sigma is a data-driven leadership approach using specific tools and methodologies that lead to fact-based decision making. This paper deals with the application of the Six Sigma methodology in reducing defects in a fine grinding process of an automotive company in India. The DMAIC (Define–Measure–Analyse–Improve–Control) approach has been followed here to solve the underlying problem of reducing process variation and improving the process yield. This paper explores how a manufacturing process can use a systematic methodology to move towards world-class quality level. The application of the Six Sigma methodology resulted in reduction of defects in the fine grinding process from 16.6 to 1.19%. The DMAIC methodology has had a significant financial impact on the profitability of the company in terms of reduction in scrap cost, man-hour saving on rework and increased output. A saving of approximately US$2.4 million per annum was reported from this project

Case study in six sigma methadology : manufacturing quality improvement and guidence for managers

This article discusses the successful implementation of Six Sigma methodology in a high precision and critical process in the manufacture of automotive products. The Six Sigma define–measure–analyse–improve–control approach resulted in a reduction of tolerance-related problems and improved the first pass yield from 85% to 99.4%. Data were collected on all possible causes and regression analysis, hypothesis testing, Taguchi methods, classification and regression tree, etc. were used to analyse the data and draw conclusions. Implementation of Six Sigma methodology had a significant financial impact on the profitability of the company. An approximate saving of US$70,000 per annum was reported, which is in addition to the customer-facing benefits of improved quality on returns and sales. The project also had the benefit of allowing the company to learn useful messages that will guide future Six Sigma activities

Quantitative storytelling in the making of a composite indicator

The reasons for and against composite indicators are briefly reviewed, as well as the available theories for their construction. After noting the strong normative dimension of these measures—which ultimately aim to ‘tell a story’, e.g. to promote the social discovery of a particular phenomenon, we inquire whether a less partisan use of a composite indicator can be proposed by allowing more latitude in the framing of its construction. We thus explore whether a composite indicator can be built to tell ‘more than one story’ and test this in practical contexts. These include measures used in convergence analysis in the field of cohesion policies and a recent case involving the World Bank’s Doing Business Index. Our experiments are built to imagine different constituencies and stakeholders who agree on the use of evidence and of statistical information while differing on the interpretation of what is relevant and vital

Rapid toxicity assessment of six antifouling booster biocides using a microplate-based chlorophyll fluorescence in Undaria pinnatifida gametophytes

Biocides of antifouling agents can cause problems in marine ecosystems by damaging to non-target algal species. Aquatic bioassays are important means of assessing the quality of water containing mixtures of contaminants and of providing a safety standard for water management in an ecological context. In this study, a rapid, sensitive and inexpensive test method was developed using free-living male and female gametophytes of the brown macroalga Undaria pinnatifida. A conventional fluorometer was employed to evaluate the acute (48 h) toxic effects of six antifouling biocides: 4,5-Dichloro-2-octyl-isothiazolone (DCOIT), diuron, irgarol, medetomidine, tolylfluanid, zinc pyrithione (ZnPT). The decreasing toxicity in male and female gametophytes as estimated by EC50 (effective concentration at which 50% inhibition occurs) values was: diuron (0.037 and 0.128 mg l(-1), respectively) > irgarol (0.096 and 0.172 mg l(-1), respectively) > tolylfluanid (0.238 and 1.028 mg l(-1), respectively) > DCOIT (1.015 and 0.890 mg l(-1), respectively) > medetomidine (12.032 and 12.763 mg l(-1), respectively). For ZnPT, 50% fluorescence inhibition of U. pinnatifida gametophytes occurred at concentrations above 0.4 mg l(-1). The Undaria method is rapid, simple, practical, and cost-effective for the detection of photosynthesis-inhibiting biocides, thus making a useful tool for testing the toxicity of antifouling agents in marine environments

A quantitative mirror on the Euribor market using implied probability density functions

This paper presents a set of probability density functions for Euribor outturns in three months’ time, estimated from the prices of options on Euribor futures. It is the first official and freely available dataset to span the complete history of Euribor futures options, thus comprising over ten years of daily data, from 13 January 1999 onwards. Time series of the statistical moments of these option-implied probability density functions are documented until April 2010. Particular attention is given to how these probability density functions, and their associated summary statistics, reacted to the unfolding financial crisis between 2007 and 2009. In doing so, it shows how option-implied probability density functions could be used to contribute to monetary policy and financial stability analysis. JEL Classification: C13, C14, G12, G13financial, financial market, options, probability density functions

Banking Sector Integration and Competition in CEMAC

This paper considers the extent of retail banking integration in the Communauté Economique et Monétaire d'Afrique Centrale (CEMAC) and the level of bank competition at the regional level. Using a mix of quantitative and qualitative indicators, the paper finds some evidence of price convergence in average interest rate spreads. However, this observed fact is not supported by an increase in cross-border flows in retail loans and deposits, and price convergence may merely reflect excess liquidity in the region. Other data also indicate that bank competition within the CEMAC as a region is limited, complementing the findings on integration. Addressing shortfalls in legal and regulatory frameworks, infrastructure, and markets would facilitate integration.Central African Economic and Monetary Community; Banks; Competition; Bank soundness; Financial soundness indicators; Monetary unions; Economic cooperation; CEMAC

Efficient isolation on Vero.DogSLAMtag cells and full genome characterization of Dolphin Morbillivirus (DMV) by next generation sequencing

The Dolphin Morbillivirus (DMV) genome from the frst Mediterranean epidemic (1990-\u201992) is the only cetacean Morbillivirus that has been completely sequenced. Here, we report the frst application of next generation sequencing (NGS) to morbillivirus infection of aquatic mammals. A viral isolate, representative of the 2006-\u201908 Mediterranean epidemic (DMV_IZSPLV_2008), efciently grew on Vero.DogSLAMtag cells and was submitted to whole genome characterization by NGS. The fnal genome length was 15,673 nucleotides, covering 99.82% of the DMV reference genome. Comparison of DMV_IZSPLV_2008 and 1990-\u201992 DMV strain sequences revealed 157 nucleotide mutations and 47 amino acid changes. The sequence similarity was 98.7% at the full genome level. Whole-genome phylogeny suggested that the DMV strain circulating during the 2006-\u201908 epidemics emerged from the 1990-\u201992 DMV strain. Viral isolation is considered the \u201cgold standard\u201d for morbillivirus diagnostics but efcient propagation of infectious virus is difcult to achieve. The successful cell replication of this strain allowed performing NGS directly from the viral RNA, without prior PCR amplifcation. We therefore provide to the scientifc community a second DMV genome, representative of another major outbreak. Interestingly, genome comparison revealed that the neglected L gene encompasses 74% of the genetic diversity and might serve as \u201chypervariable\u201d target for strain characterization

Three Attempts at Inflation Forecasting in Pakistan

This paper presents three empirical approaches to forecasting inflation in Pakistan. The preferred approach is a leading indicators model in which broad money growth and private sector credit growth help forecast inflation. A univariate approach also yields reasonable forecasts, but seems less suited to capturing turning points. A vector autoregressive (VAR) model illustrates how monetary developments can be described by a Phillips-curve type relationship. We deal with potential parameter instability on account of fundamental changes in Pakistan’s economic system by restricting our sample to more recent observations. Gregorian and Islamic calendar seasonality are addressed by using 12-month moving averages.Inflation, Forecasting, Pakistan

A Universal Live Cell Barcoding-Platform for Multiplexed Human Single Cell Analysis.

Single-cell barcoding enables the combined processing and acquisition of multiple individual samples as one. This maximizes assay efficiency and eliminates technical variability in both sample preparation and analysis. Remaining challenges are the barcoding of live, unprocessed cells to increase downstream assay performance combined with the flexibility of the approach towards a broad range of cell types. To that end, we developed a novel antibody-based platform that allows the robust barcoding of live human cells for mass cytometry (CyTOF). By targeting both the MHC class I complex (beta-2-microglobulin) and a broadly expressed sodium-potassium ATPase-subunit (CD298) with platinum-conjugated antibodies, human immune cells, stem cells as well as tumor cells could be multiplexed in the same single-cell assay. In addition, we present a novel palladium-based covalent viability reagent compatible with this barcoding strategy. Altogether, this platform enables mass cytometry-based, live-cell barcoding across a multitude of human sample types and provides a scheme for multiplexed barcoding of human single-cell assays in general

Forecasting Construction Tender Price Index in Ghana using Autoregressive Integrated Moving Average with Exogenous Variables Model

Prices of construction resources keep on fluctuating due to unstable economic situations that have been experienced over the years. Clients knowledge of their financial commitments toward their intended project remains the basis for their final decision. The use of construction tender price index provides a realistic estimate at the early stage of the project. Tender price index (TPI) is influenced by various economic factors, hence there are several statistical techniques that have been employed in forecasting. Some of these include regression, time series, vector error correction among others. However, in recent times the integrated modelling approach is gaining popularity due to its ability to give powerful predictive accuracy. Thus, in line with this assumption, the aim of this study is to apply autoregressive integrated moving average with exogenous variables (ARIMAX) in modelling TPI. The results showed that ARIMAX model has a better predictive ability than the use of the single approach. The study further confirms the earlier position of previous research of the need to use the integrated model technique in forecasting TPI. This model will assist practitioners to forecast the future values of tender price index. Although the study focuses on the Ghanaian economy, the findings can be broadly applicable to other developing countries which share similar economic characteristics