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An adaptive CUSUM (ACUSUM) control chart got special attention against classical CUSUM control chart to detect a shift of different sizes in the process location. Similarly, an ACUSUM based on classical EWMA statistic and score function, denoted as a ACUSUM E control chart, is improved form of classical CUSUM control chart and can identify different sizes of shift. Classical EWMA statistic in ACUSUM E control chart fails to offer clear instruction for parameter values to identify a precise shift as the classical CUSUM statistic does. To address this issue, this study proposed two ACUSUM control charts, symbolized as ACUSUM C 1 and ACUSUM C 2 to further improve detection ability of shift in the process location. Novelty of the proposed control charts is to initially adaptively renew reference parameters values based on classical CUSUM statistic and then to assign a weight on it using score functions. An algorithm is developed in MATLAB using Monte Carlo simulation method to obtain numerical results. Based on numerical results, performance measures such as average run length for a specific shift, extra quadratic loss, relative average run length, and performance comparison index for overall performance are calculated for comparison purpose. Comparison based on visual presentation and numerical results reveals the proposed control charts performed quite effective against some existing control charts. It is worthy to mention, classical CUSUM control chart is special cases of proposed ACUSUM C 1 control charts at specific values of parameter. Finally, proposed control charts are also implemented on real-life data to show practical significance to users and practitioners. [ABSTRACT FROM AUTHOR]

An illumination normalization algorithm for face images is proposed. For preprocessing of the input image, low light is enhanced to improve image quality. The reflection layer of image is normalized for edge preservation and to remove the artifacts, which is added to a small-scale image. Noise is removed, and details are enhanced to improve the quality of the image. Contrast is corrected by histogram truncation. Shape from shading is extracted and passed through a guided filter to acquire a face image having illumination normalized. Simulation outcome on Multi-PIE, CAS-PEAL, and Extended Yale B face dataset shows the strength of the suggested approach. [ABSTRACT FROM AUTHOR]

Statistical process control provides package of statistical tools applied for improving quality of manufacturing, production and services processes. Cumulative sum, exponentially weighted moving average (EWMA) and progressive mean charts belong to family of memory-type charts which effectively spot small and persistent shifts in the process parameter(s). EWMA chart requires normality and a proper choice of smoothing parameter to perform efficiently. Any deviation from these conditions affects its performance in terms of efficacy and robustness. For the said concerns, progressive exponentially weighted moving average (PEWMA) chart is developed to monitor the shifts in the process location. The performance of the proposed PEWMA chart is evaluated in terms of average run length and some other metrics of run length distribution. The assessment of the proposed chart has been made under standard normal, Student's t, gamma, Laplace, logistic, exponential, contaminated normal and lognormal distributions. The performance of the proposed PEWMA chart is also compared with some existing competitors including the classical EWMA, classical CUSUM, HWMA, MEC, MCE and DEWMA charts. The analysis reveals that the proposal offers a design structure which has high sensitivity to small and persistent drifts in the process mean and has advantage of robustness under non-normal scenarios. An application from substrates manufacturing process (in which flow width of the resist is the key quality characteristic) is also provided for practical implementations. [ABSTRACT FROM AUTHOR]

Statistical quality control is an integral part of modern manufacturing, and control charts are widely used to improve and control the performance of a process. However, much of the work related to process monitoring has been done using frequentist approaches, whereas the Bayesian methodology has a practical advantage in process monitoring; that is, it can be used with a small phase-I dataset. In this article, we considered different symmetric and asymmetric loss functions for designing Bayesian control charts and noticed that the performance of the Bayesian charts is biased, i.e., in-control performance of the charts is not equal to the desired value for some loss functions and comparison among different Bayesian charts can be misleading. Therefore, to get the desired in-control performance under different loss functions, we propose a corrected design of the Bayesian control charts. In addition to posterior charts, we also discuss a predictive control chart to monitor the future observations in this study. Besides a simulation study, we also present two real data examples: the first example is to monitor the surface roughness of reamed holes in a particular metal part while the second is about monitoring the measurements of a diameter. [ABSTRACT FROM AUTHOR]

According to the recent chronostratigraphic division of Cambrian, the Cambrian strata in the Kelan section can be subdivided into seven third-order sequences (DS1-DS7) based on cyclicity in sedimentary facies stacking patterns. The calcareous mudstone forming condensed section, micritic limestone comprising deep to middle ramp facies and the oolitic-grain bank facies in Series 3 and Furongian series represent the basic depositional fabric of Cambrian in northwestern part of Shanxi Province, North China Platform. These massive oolitic grainstones demonstrate that the oolitic-grain bank facies constitute the late-highstand systems tract or forced-regressive systems tract. The grains occupy upper parts of the third-order depositional sequences in response to relative sea-level fall. Furthermore, this forming pattern of oolitic-grain bank facies does not follow the standard model of sequence stratigraphy, in which deposition is believed to occur principally during sea-level rise, rather a continuous erosional unconformity develops during sea-level fall. Moreover, the microscopic analysis of oolitic grainstone shows the development of concentric and radial, rounded or elliptical, with or without nuclei, monocrystalline or polycrystalline, Girvanella or micritic ooids. The occurrence of diversified ooids in varying proportions provides a new dimension for studying evolution of the oolitic-grain bank in the North China Platform. The forming pattern of oolitic-grain bank controlled by their sequence-stratigraphic position in the Kelan section in the Shanxi province provides an important clue and a research direction for the regional correlation, as well as the paleogeographical reconstruction of the Cambrian Series 3 and Furongian series. [ABSTRACT FROM AUTHOR]

An adaptive cumulative sum (CUSUM) control chart based on the classical exponential weighted moving average (EWMA) statistic and Huber's function, symbolized as an ACUSUM E control chart, is an enhanced form of the classical CUSUM control chart that can identify different sizes of shift. However, the classical EWMA statistic for the ACUSUM E control chart does not provide explicit rule for parameter choices to diagnose a specific shift. To overcome this issue, this study has proposed two ACUSUM control charts, symbolized as ACUSUM c control charts to monitor a specific and a certain range of shift. The novelty behind the proposed ACUSUM c ( ACUSUM c 1 and ACUSUM c 2 ) control charts is initially adaptively updating the reference parameter using the classical CUSUM statistic, generalized likelihood ratio test, and score functions to achieve superior performance. An algorithm in MATLAB using the Monte Carlo simulation technique is designed to obtain numerical results. Furthermore, based on numerical results, performance evaluation measures such as average run length, extra quadratic loss, relative average run length, and comparison index are calculated. The proposed ACUSUM C control charts based on performance evaluation measures and visual presentation are compared against other control charts. Findings reveal the superiority of the proposed ACUSUM C control charts. Besides, for practical point of view, the proposed ACUSUM C 1 control chart is implemented with numerical data to show the significance over other control charts. [ABSTRACT FROM AUTHOR]

Deep learning-based pansharpening has emerged as a dynamic research area. Retaining spatial & spectral characteristics of panchromatic image and multispectral bands are a critical issue in pansharpening. This paper proposes a pyramid-based deep fusion framework that preserves spectral and spatial characteristics at different scales. The spectral information is preserved by passing the corresponding low-resolution multispectral image as residual component of the network at each scale. The spatial information is preserved by training the network at each scale with the high frequencies of panchromatic image alongside the corresponding low resolution multispectral image. The parameters of different networks are shared across the pyramid in order to add spatial details consistently across scales. The parameters are also shared across fusion layers within a network at a specific scale. Experiments show that the proposed architecture exhibits better performance than state-of-the-art pansharpening models. At reduced scale, the proposed scheme has enhanced the fusion quality in terms of universal quality index, spectral angle mapper, relative global error, and spatial correlation coefficient by 9.6 % , 33.1 % , 36 % , and 11.2 % , respectively. Similarly, at full scale, the fusion performance is improved in terms of spectral & spatial distortions, and no reference quality metrics by 47.3 % , 36.7 % , and 9.5 % , respectively. [ABSTRACT FROM AUTHOR]

The rapid depletion of natural sand resources due to extensive usage in construction demands the need for an alternative and economical fine aggregate. The present study evaluates the physico-mechanical and petrographic properties of stone dust and concrete using stone dust as a fine aggregate replacement for natural sand. A comparative analysis of sand (conventional) and stone dust (alternative) as a fine aggregate was carried out through several tests for physical characteristics, petrographic and geochemical analysis (X-ray fluorescence) along with physico-mechanical tests on the concrete. Different trial mixes of M25 grade concrete were prepared as per American Concrete Institute (ACI) standards with various replacement percentages of stone dust with natural sand. These trail mixes were then subjected to the slump test of fresh concrete and other physico-mechanical tests were performed as per American Society for Testing and Materials (ASTM) standards on 7 and 28 days hardened concrete cylinders and slabs. The physical and chemical properties of stone dust are within the ASTM standard limits for fine aggregate used in cement concrete. The slump values of fresh concrete range between 27 and 74 mm for all mix designs. The replacement of sand with stone dust at various ratios in medium-grade concrete showed an increase of up to 40 and 29% in compressive and up to 53 and 32% in flexural strengths for 7- and 28-day curing periods, respectively, in comparison to concrete mix using 100% natural sand. The strength values of all concrete samples using stone dust surpass the minimum strength requirements of the M25 concrete mix design. The most favourable replacement combination of natural sand with stone dust is 40–60% depending upon the type and application of the mix design. The present study suggests the reuse of quarry waste as an economical replacement for depleting resources of natural sand. [ABSTRACT FROM AUTHOR]

In many manufacturing industries, quality of an item depends on different characteristics and their relationship may be modeled by profiles. For instance, in photo-voltaic (PV) system, output voltage is dependent on the capacitance level of capacitors, used in the Z-source inverter. Control chart is a dynamic tool that works under two different phases namely Phase I and Phase II. The unknown parameters are estimated in Phase I, while Phase II focuses on monitoring of the process using estimated control limits from Phase I. In this study, we have investigated Phase I monitoring of linear profile parameters under several sampling approaches including ranked set sampling (RSS), double RSS, median RSS (MRSS), double MRSS, extreme RSS (ERSS) and double ERSS. A comparative analysis on the performance of existing and proposed schemes is performed in terms of probability to signal. The results advocate that the proposed methods under different ranked set schemes offer superior detection abilities as compared to the existing schemes for varying shifts in profile parameters (intercept, slope and error variance). Moreover, a real application related to PV system is included to show the practical demonstration of the profile monitoring (for the output voltage in relation to capacitance level) under proposed schemes. [ABSTRACT FROM AUTHOR]

Efficient control charts are used to maintain and improve the manufacturing, industrial and service processes. Control chart is a basic tool of quality practitioners for producing products that meet market requirements in terms of quality, reliability and functionality. Lack of normality is a common occurrence in these processes. In such situations, distribution-free control charts are increasingly used for process monitoring. The nonparametric exponentially weighted moving average chart is a frequently used memory-type control chart in the process monitoring. The drawback of this chart is that it performs efficiently only on smaller values of the smoothing parameter. To compensate this drawback, a modified nonparametric exponentially weighted moving average chart under progressive setup based on sign and arcsine test statistics is proposed in this study. The prominent quality of the proposed scheme is that it performs efficiently in detecting small and persistent shifts in the process location under each choice of the smoothing parameter. The performance of the proposed chart has been investigated through simulations that use run length profiles (average run length, median run length and standard deviation of run length). When the performance of the proposed chart is compared with alternatives, its ability to detect small and persistent shifts is much better. Two real-life applications associated with hard-bake and piston rings manufacturing processes are included that show the demonstration of the proposed charts. [ABSTRACT FROM AUTHOR]

Five organotin complexes with general formulae [LCSSSnR2]n (R = Me, n-Bu, Ph) and R3SnLCSSSnR3 (R = n-Bu, Ph) were synthesized by the reaction of equimolar quantities of sarcosine (HLH) with KOH, CS2 and either R2SnCl2 (R = Me, n-Bu, Ph) or R3SnCl (R = n-Bu, Ph) in methanol. Elemental (CHNS) analyses data and mass spectroscopy agreed well with the molecular composition of the synthesized products. FTIR spectroscopy verified the monodentate binding mode of the carboxylate group and a bidentate chelating behavior of the dithiocarboxylate moiety of the ligand for binding with tin(IV). Thus, penta- and hexa-coordinated environments around tin were observed in the solid state in di- and triorganotin complexes, respectively. The penta-coordinated geometry in diorganotin(IV) product 2 was further verified by its single-crystal XRD analysis. The organotin moieties and ligand units were interconnected with each other alternately in hexameric cyclic arrangement. The number of protons found in 1H NMR spectra was in good agreement with those calculated by incremental method. Complexes were examined for their antioxidant, antimicrobial, antidiabetic, thrombolytic, hemolytic activities. The free ligand HLH was found inactive against all the four bacterial strains. [ABSTRACT FROM AUTHOR]

After the global extinction event at the end of the Cambrian Epoch 2, widely spread oolitic bank dominated the North China Carbonate Platform during the Cambrian Miaolingian Epoch. To better understand the influence of paleogeographic and paleoenvironmental factors on microbial carbonate particles during this period, carbonate oncoids of the Cambrian Miaolingian Series were selected to reconstruct the paleogeography and paleoenvironment. The study samples were collected from four different sections: Wuhai, Diaoquan, Xiawidian and Sandaogou (from west to east in the North China Platform). Stratigraphic, sedimentological, petrological and geochemical studies including analysis of trace and rare earth elements were carried out to define the stratigraphic location, and morphological and geochemical characteristics of oncoids. Geochemical analysis of oncoids reveals that Er/Nd and Y/Ho values are relatively low, signifying that the formation of oncoids was influenced by terrestrial inputs. Meanwhile, Sr/Cu, Sr/Ba, V/Sc and V/Cr values indicate that the oncoids were developed in a shallow marine environment under oxidizing conditions. The low content of total rare earth elements, low LREE/HREE ratios and LREEs, negative anomalies of Ce/Ce* and Eu/Eu* as well as (La/Sm)N suggest that the oncoids were less influenced by late diagenetic processes. More importantly, morphological differentiations of oncoids in the study area coincide with the changing trend of Y/Ho and Sr/Ba. The results of this study show that oncoids with regular morphology mainly formed at offshore area, while those with irregular shape and preserving rough laminae mostly occurred at nearshore area. From the comparison made between the paleogeographic locations of the study sections, it is proposed that the paleosalinity of marine depositional environment and the transportation distance are the prime controls for morphological differentiation of oncoids. [ABSTRACT FROM AUTHOR]

Monitoring of process parameters via control charts is exceptionally common exercise in statistical process control (SPC). The exponentially weighted moving average (EWMA) control chart is one of an outstanding powerful tool of the SPC for monitoring of process parameters. The performance of any process can be improved by the careful monitoring and removing of assignable causes of variation. The existence of outliers may influence the performance of traditional charts in the monitoring of a process. This study is planned for the monitoring of dispersion parameter through the interquartile range (IQR). We proposed EWMA-type IQR charts based on auxiliary information for the efficient monitoring of process dispersion for the process following bivariate normal distribution. The comparison of these charts is made with usual IQR chart as well as traditional R and S charts. We evaluate the efficiency of charts by some commonly used run length measures. Both contaminated and uncontaminated processes are considered in this study to examine the robustness of charts. The results revealed that our proposed control charts exhibit superior performance in the presence of outliers. A real application of our study is also provided based on non-iso-thermal continuous stirred tank chemical reactor process. [ABSTRACT FROM AUTHOR]