A zero‐inflated Poisson (ZIP) process is different from a standard Poisson process in that it results in a greater number of zeros. It can be used to model defect counts in manufacturing processes with occasional occurrences of non‐conforming products. ZIP models have been developed assuming that random shocks occur independently with probability p, and the number of non‐conformities in a product subject to a random shock follows a Poisson distribution with parameter λ. In our paper, a control charting procedure using a combination of two cumulative sum (CUSUM) charts is proposed for monitoring increases in the two parameters of the ZIP process. Furthermore, we consider a single CUSUM chart for detecting simultaneous increases in the two parameters. Simulation results show that a ZIP‐Shewhart chart is insensitive to shifts in p and smaller shifts in λ in terms of the average number of observations to signal. Comparisons between the combined CUSUM method and the single CUSUM chart show that the latter's performance is worse when there are only increases in p, but better when there are only increases in λ or when both parameters increase. The combined CUSUM method, however, is much better than the single CUSUM chart when one parameter increases while the other decreases. Finally, we present a case study from the light‐emitting diode packaging industry. Copyright © 2011 John Wiley & Sons, Ltd.

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This paper considers the problem of monitoring the proportion p of nonconforming items when a continuous stream of Bernoulli observations is available and the objective is to effectively detect a wide range of increases in p. The proposed control chart is based on a generalized likelihood ratio (GLR) statistic obtained from a moving window of past Bernoulli observations. The Phase II performance of this chart in detecting sustained increases in p is evaluated using the steady state average number of observations to signal. Comparisons of the Bernoulli GLR chart to the Shewhart CCC-r chart, the Bernoulli cumulative sum chart, and the Bernoulli exponentially weighted moving average chart show that the overall performance of the Bernoulli GLR chart is better than its competitors. In addition, methods are provided for designing the Bernoulli GLR chart so that this chart can be easily applied in practice.

In 2015, African ministers established the Ngor Declaration to achieve universal access to adequate sanitation and hygiene services and eliminate open defecation by 2030. Realizing this target will require significant public and private investment. Over the last two decades, there has been increasing recognition that sanitation programs should be demand driven, yet limited information exists about how much rural residents in developing countries are willing to pay for sanitation improvements. This paper applies the contingent valuation approach to evaluate how much households in rural Senegal are willing to pay for a ventilated improved pit (VIP) latrine. The analysis uses data from 1,635 household surveys that were conducted in 47 rural communities across four regions in Senegal. The willingness to pay model found that respondents were more willing to pay for a VIP latrine if they had plans to improve their existing latrine, lived in districts located nearer to the capital city of Dakar, were dissatisfied with their existing sanitation service, and were male. The analysis also indicates that the current household contribution of 5% of the costs of constructing a VIP latrine could be increased to 30% with only a modest decline in the number of households willing to pay this amount.

In the process of promoting the national territorial spatial planning system in all provinces, cities and counties, the geospatial database of "One Map" has realized the information sharing and collaborative work of multiple departments. Based on this, this paper intended to provide a set of standardized mapping models for industrial heritage storage, and through the establishment of the database to protect and reuse the status quo of industrial heritage research. This paper took the third-line construction industrial heritage of Mianyang "Two-Bomb City" as the research object, developed the relevant drawing standards of third-line industrial heritage database, and studied the database construction process. GIS technology is used to establish a geospatial database of the third-line industrial heritage in cooperation with the "One Map" system, in order to provide reference for the storage of the third-line industrial heritage in various places, and to protect and reuse the third-line industrial heritage from the perspectives of spatial factors, planning coordination and dynamic assessment.