Quality Control Inspection Research Articles

The quality control effect of PDCA cycle in operation safety check

Objective To explore the quality control effect of PDCA cycle in surgical safety verification. Methods The first class of quality control information was collected for the operation safety inspection implementation situation of operating room in this hospital from April to September 2015.In addition, PDCA circulation method was used to analyze the operation safety inspection situation of quality control inspection to find the weak links in the process of implementation.In addition, the specific measures were taken to have 3 months of learning and continuous improvement.Additionally, the operation safety inspection implementation rates before and after PDCA would be compared. Results For the comparison before and after overall safety inspection implementation rates, and the comparison of implementation rates before and after the weak links of medication, anaesthesia and nursing, the difference had statistical significance(P<0.05). Conclusions The application of PDCA cycle to the nursing quality control of surgical safety verification can provide insight into the weak links in the quality control management of surgical safety verification.It can indicate the direction of decision for the manager, significantly improve the operation safety audit execution rate and nursing management quality. Key words: PDCA cycle; Surgical safety check; Quality control; Nursing management

Sag Bending Control in the Production of Automobile Windshields

Random inspection quality control of laminated windshields during sag molding was performed. The deviations from the technical specifications of the surface tensile stresses at the edge of the glass were revealed. Adaptive models describing the dependence of the tensile stresses at the glass edge on the sag bending temperature were constructed. An algorithm was developed for controlling the sag bending temperature. It is shown by means of simulation modeling that the magnitude of the surface tensile stresses in the produced articles can be stabilized.

Quality control process improvement of flexible printed circuit board by FMEA

This research focuses on the quality control process improvement of Flexible Printed Circuit Board (FPCB), centred around model 7-Flex, by using Failure Mode and Effect Analysis (FMEA) method to decrease proportion of defective finished goods that are found at the final inspection process. Due to a number of defective units that were found at the final inspection process, high scraps may be escaped to customers. The problem comes from poor quality control process which is not efficient enough to filter defective products from in-process because there is no In-Process Quality Control (IPQC) or sampling inspection in the process. Therefore, the quality control process has to be improved by setting inspection gates and IPCQs at critical processes in order to filter the defective products. The critical processes are analysed by the FMEA method. IPQC is used for detecting defective products and reducing chances of defective finished goods escaped to the customers. Reducing proportion of defective finished goods also decreases scrap cost because finished goods incur higher scrap cost than work in-process. Moreover, defective products that are found during process can reflect the abnormal processes; therefore, engineers and operators should timely solve the problems. Improved quality control was implemented for 7-Flex production lines from July 2017 to September 2017. The result shows decreasing of the average proportion of defective finished goods and the average of Customer Manufacturers Lot Reject Rate (%LRR of CMs) equal to 4.5% and 4.1% respectively. Furthermore, cost saving of this quality control process equals to 100K Baht.

Enhancing The Speed of Inspection in Coordinate Measuring Machine Using Genetic Algorithm

Due to high accuracy and precision, coordinate measuring machine (CMM) has been an important tool of inspection in quality control for several years. Effectiveness of inspection greatly depends on measurement cycle time. Lesser the inspection time taken by CMM to measure a given part better will be the performance of inspection process. Therefore, for efficient performance of inspection process, it is critical to reduce measurement time. Goal of our research is to improve measurement accuracy and reduce the cycle time of inspection. There are various methods to generate most suitable measurement path which will result in minimum inspection time. These methods are based on different algorithms to reduce measurement cycle time for CMM. Genetic algorithm, which is one of the optimization techniques can be used to find the minimum cycle path and hence can be used to increase the speed of inspection.

Robust active vision industrial CAD parts recognition system

In automated assembly systems the machine parts identification is entirely different from simple object recognition; moreover the ability of humans to differentiate between correct and not correct machine parts is better but it is a difficult task for a machine. In general, with fast moving machine parts on the conveyor manual defect detection by human inspectors is impractical. Also it is expensive, inaccurate, subjective, eye straining and causes other health issues to quality control inspectors. A computer vision-based non-contact inspection technique is developed with image processing methods by considering these problems, for defect detection in industrial machine parts. The present work will help the industrial robot used in assembly process and industrial inspection systems. In this paper features-based industrial object detection techniques are implemented in MATLAB to recognise the presence of the industrial CAD parts in the query image. In the end the actual industrial tool images are also used to show the accuracy and robustness of the proposed machine vision system for industrial manufacturing automation.

Artificial neuronal networks for optical inspection in PCB quality control

This paper is the result of the research work on the application of an artificial neural network algorithm applied in decision making in the process of AIO (Automatic Optical Inspection) for quality control from an electronic prototyping company, generating models for the assurance of Quality in the PCB (Printed Circuit Board) product, covering the fields of decision making, quality management, production processes, neural computer systems and artificial vision among others. It is intended to develop an algorithm of artificial neural networks that provides an approach to human recognition and perception when performing a quality inspection of the final product, based on image analysis and recognition. It is presented the theoretical concepts explored and the results obtained. Initially a problem definition was made to model, then the data processing was performed, the artificial neural network model was selected to be applied, then the relevant adjustments made to the model to finally obtain a simulation and validation of the same

Measurement uncertainty and its application to standards in acoustics

The basic theory of measurement uncertainty as found in IEC and ISO standards is reviewed. Random error, bias error, confidence interval, coverage factor, and expanded uncertainty are defined. The concept of acceptance intervals applied to tolerance limits on the performance of electroacoustical systems for outgoing quality control and incoming inspection is presented. Calculation of the maximum permitted uncertainty is detailed and its application in the development of an uncertainty budget for a given electroacoustical measurement is shown. Example uncertainty budgets are developed for response measurements on a number of common electroacoustical devices including loudspeakers, microphones, telephones, earphones, and hearing aids. In addition to using this method to develop an uncertainty budget, it is shown how it can also be used as a diagnostic tool to find problems in the specification of various components in a measurement chain. An example of its diagnostic use on the current version of the ANSI S3.22 hearing aid standard is shown. Last, the uncertainty is calculated for a measurement of random noise and its dependence on bandwidth and averaging time is examined.

Ultrasonic non-destructive testing of cardboard tubes using air-coupled transducers

Cardboard tubes are commonly used for industrial plastic film wrapping due to their low cost, high compression strength, reliability and low sensitivity to environmental changes. In order to guarantee the high radial compression strength during the manufacturing process, destructive testing such as manual peeling or non-destructive testing using acoustic impedance measurements are currently performed on a regular basis. In order to achieve a continuous quality control, automatic and non-contact inspection still need to be developed. In this paper, a method and apparatus for non-contact and rapid inspection of cardboard tubes is presented. The principle is based on the use of capacitive air-coupled transducers at frequencies below 20 kHz for generation and measurement of propagative flexural waves in a pitch-and-catch configuration. Sensitivity analysis is performed for different modes and damage types and is validated experimentally for four flaw types typically observed during the manufacturing process. Experimental validation of detection and flaw quantification is demonstrated using both amplitude and time-of-flight of wave packets at different frequencies, allowing automatic quality control of the manufacturing process.

A generalized approach to economic design of control charts: A discussion on implementing

ABSTRACTDue to the importance of choosing between uniform and non uniform sampling schemes in quality control inspections, two generalized models for the economic design of control charts under both schemes are presented separately in this paper. Under uniform sampling plan, two leading models of Lorenzen and Vance (1986) and McWilliams (1989) can be obtained by applying, respectively, Exponential and Weibull in-control time distributions in the uniform generalized model. Furthermore, the generalized model of Rahim and Banerjee (1993) is achieved by using an alternative approach under arbitrary sampling interval plan. These outcomes lead us to present a comprehensive discussion on implementing the economic and economic statistical design of control charts. By imposing a new proposed restriction on the economic model, we can guarantee to have control charts whose power to report the true alarm at the end of each sampling interval is more than shift conditional probability over that interval given no shift till its start. The new restricted economic model, which we call “high-powered economic design of control charts”, can be considered as a special case of economic statistical design. The advantages of our proposed model are highlighted by some numerical examples.

Helium permeation as a fast quality indicator for barrier properties of solar cell encapsulates

AbstractThe advent of flexible electronic devices and flexible thin‐film photovoltaic modules increases the need for transparent and flexible high‐barrier films. Conventional methods for measuring the barrier properties of such films are costly and time consuming. In our work, we present a method where we correlate water vapor and helium transmission rate measurements on strained barrier films with thin‐film solar module performance. We show that the detected properties correlate well with the performance of a CIGS mini module exposed to damp‐heat environment. The critical strain limit for a substantial decrease in barrier properties was identified for an ETFE‐based barrier film incorporating an inorganic barrier layer. It was found that the detection of the helium transmission rate provides a fast and reliable way to identify damage to barrier films and is therefore suitable as means for quality control or incoming goods inspection.

Real-time microscopic 3D shape measurement based on optimized pulse-width-modulation binary fringe projection

In recent years, tremendous progress has been made in 3D measurement techniques, contributing to the realization of faster and more accurate 3D measurement. As a representative of these techniques, fringe projection profilometry (FPP) has become a commonly used method for real-time 3D measurement, such as real-time quality control and online inspection. To date, most related research has been concerned with macroscopic 3D measurement, but microscopic 3D measurement, especially real-time microscopic 3D measurement, is rarely reported. However, microscopic 3D measurement plays an important role in 3D metrology and is indispensable in some applications in measuring micro scale objects like the accurate metrology of MEMS components of the final devices to ensure their proper performance. In this paper, we proposed a method which effectively combines optimized binary structured patterns with a number–theoretical phase unwrapping algorithm to realize real-time microscopic 3D measurement. A slight defocusing of our optimized binary patterns can considerably alleviate the measurement error based on four-step phase-shifting FPP, providing the binary patterns with a comparable performance to ideal sinusoidal patterns. The static measurement accuracy can reach 8 μm, and the experimental results of a vibrating earphone diaphragm reveal that our system can successfully realize real-time 3D measurement of 120 frames per second (FPS) with a measurement range of in lateral and 8 mm in depth.

A System for Automated Detection of Ampoule Injection Impurities

Ampoule injection is a routinely used treatment in hospitals due to its rapid effect after intravenous injection. During manufacturing, tiny foreign particles can be present in the ampoule injection. Therefore, strict inspection must be performed before ampoule injections can be sold for hospital use. In the quality control inspection process, most ampoule enterprises still rely on manual inspection which suffers from inherent inconsistency and unreliability. This paper reports an automated system for inspecting foreign particles within ampoule injections. A custom-designed hardware platform is applied for ampoule transportation, particle agitation, and image capturing and analysis. Constructed trajectories of moving objects within liquid are proposed for use to differentiate foreign particles from air bubbles and random noise. To accurately classify foreign particles, multiple features including particle area, mean gray value, geometric invariant moments, and wavelet packet energy spectrum are used in supervised learning to generate feature vectors. The results show that the proposed algorithm is effective in classifying foreign particles and reducing false positive rates. The automated inspection system inspects over 150 ampoule injections per minute (versus ~ 12 ampoule injections per minute by technologist) with higher accuracy and repeatability. In addition, the automated system is capable of diagnosing impurity types while existing inspection systems are not able to classify detected particles.

Practical implementation of the PIC/S principles in Ukraine after its accepting international requirements for quality control of medicinal products

Pharmaceutical Inspection Cooperation Scheme (PIC/S) is an international instrument of interaction between countries and regulatory authorities in the sphere of quality control of medicines (by national pharmaceutical inspectorates), which together provide an active and constructive cooperation in the field of good manufacturing practices (GMP), inspection and licensing. Aim. To develop a strategy, tactics and sequence of applying adaptation mechanisms to the pharmaceutical industry legislation of Ukraine according to EU and the PIC/S requirements. Results. In 2010, within Ukraine joining to the PIC/S the starting audit of researches on adaptation of medicinal products quality standards to the international requirements was carried out. In the period from March 22 to 26, 2010 the PIC/S audit team performed the final audit in order to check the readiness of Ukraine to join the PIC/S. On November 8,2010 a decision on Ukraine’s membership was made in Kuala Lumpur (Malaysia). Since January1, 2011 Ukraine has become the PIC/S member within the system of medicinal products circulation and quality control in accordance with GMP/GDP and EU Directive 2001/83/EC. During the period of Ukraine’s accession to the PIC/S system, accordingly, this Directive was improved. At the VIII National pharmaceutical Congress (Kharkiv, September 14-16, 2016) 26 additions to the decision of Congress were proposed, including questions related to the PIC/S and other legislative initiatives. Conclusions. Legislative documents of the system of medicines quality control and circulation inspection are the international requirements of the PIC/S. The principles, measures and requirements were developed, discussed and accepted that contributed to the accession of Ukraine to the PIC/S system in 2011.

Post Marketing Study of Ponstan®500 mg Tablet under Suspicion as Counterfeit Drug at Pharmacies

Ponstan® (Mefenamic Acid 500 mg) is one of a few commonly counterfeited drugs in Indonesia. Drug counterfeiting would adversely affect consumers in terms of finances and health. Local health authority rarely conducted market inspection to address such problem. This study was conducted to determine whether Ponstan® sold at pharmacies in the vicinity of public hospital were counterfeit drugs, based on tablets physical characteristics and active substance contents with regards of the Pharmacopeia Indonesia 4th Edition requirements. This study used Ponstan® sampled from pharmacies within 1 kilometer radius of Class A or B public hospitals in Malang. The packages and tablets were physically inspected, and mefenamic acid assayed by using spectrophotometric method at 285 nm. All of the samples showed similar physical characteristics when compared to the original Ponstan®. Of total 66 tablets collected from 22 pharmacies, mefenamic acid contents were ranging from 94.58% to 111.72% of that listed on their labels, with 3.03% (2/66) contained more than 110%. It can be concluded that 96.97% (64/66) of Ponstan® tablets collected from sampled pharmacies meet the requirements of Pharmacopeia Indonesia 4th Edition, whereas the other 3.03% belong to “not conformed product” during quality control inspection.

Effects of an electric field shield on the neutralizing characteristics of a corona discharge air ionizer

The effects of an electric field shield on the electric field noise and neutralizing current of a corona discharge air ionizer were investigated as a means to prevent soft errors during quality control inspections. The neutralizing current and noise voltage were measured for shielded and nonshielded air ionizers using a charged plate monitor. The use of an electric field shield decreased both the neutralizing current and the noise voltage. Therefore, neutralizing current to noise voltage ratio was calculated to evaluate the effect of the shield on the neutralization performance, and this ratio was several times higher for the shielded air ionizer than for the nonshielded air ionizer. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley &amp; Sons, Inc.

Optimal inspection of a finite population

ABSTRACTThis article presents a method for determining an optimal quality control (QC) inspection frequency for a manufacturing process where a specified number of items will be produced and where, if the process goes out of control and generates a defective item, it stays out of control. In addition, there is a QC inspection procedure than can detect a defective item. The frequency of inspection is based on minimizing the total cost. The total cost includes the cost of QC inspections plus the cost of manufacturing defective items. In this application the cost of manufacturing defective items is, after identifying a defective item, the cost of checking previously manufactured items until it is determined when the process went out of control, i.e., until a good item is found.

Efficient, Unbiased Quality Assurance Of Automated Tissue Analysis Applicable To Daily Pathology Practice

Introduction/ Background Quantification of tissue biomarkers is increasingly demanded for diagnosis and is commonly performed by expert pathologists using microscopy of stained tissue at high magnification. This manual scoring is a reasonably fast, supervised procedure, but it suffers from inter- and intra-observer differences due to a) differences in selection of regions of interest, b) differences in quantity estimation, c) intra-tissue variability of biomarker expression. Computers and whole slide microscopy scanners have made it feasible to perform high-capacity analysis of high resolution images of tissue. Image analysis (IA) enables better reproducibility, but conversely, the unsupervised analysis introduces challenges regarding accuracy. Furthermore, borderline cases will always have to be rigorously inspected by pathologists. Many IA evaluation methods exist, but for pathology, a supervised comparison of experimental segmentation to an appropriately obtained standard criterion is the optimal strategy. The production of standard criterion necessitates evaluation of whole slide images to eliminate any possible region sampling bias while inter- and intra- observer bias can only be minimized by replacing any manual estimates by objective measurements. A logical step is thus to change the task of the pathologist from quantity estimation to verifying the output an automated procedure reports. Still, verification of entire tissue slides is in daily pathology practice too time-consuming. To minimize the workload pathology is turning to stereological methods which aim to efficiently quantify matter unbiasedly and have been proved useful for supervised validation of automated analysis for Ki67 scoring of breast cancer. However, the workload still needs to be reduced to a level comparable to the manual scoring procedure. Aims We aim to enable high accuracy, objective evaluation of automated image analysis with a workload and workflow feasible for daily pathology practice. This regards both production of reference data for image analysis tool calibration and continuous quality control inspection of borderline cases. Methods This study investigates proportionate sampling, a very efficient stereological sampling scheme utilizing weighted sampling of regions of automated image analysis for manual evaluation of automated IA. The sampling of regions to be inspected by a pathologist draws upon the IA to assign probability weights to all regions. This results in a highly efficient, unbiased sampling and quality assurance estimate for the automated image analysis. Results Presented here is proof-of-concept of an efficient, unbiased image analysis evaluation methodology. The task of the pathologist is changed from quantity estimation to instead annotate discrepancies between the output from the IA and the tissue in a few sampled regions. From the annotations an unbiased quality assurance estimate of the IA can be estimated including levels of accuracy obtainable and expected workloads. This confirms that the stereological proportionate sampling enables manual verification of automated whole slide image analysis for unbiased reference dataset creation and quality control inspection in borderline cases. Furthermore, the methodology is easily integrated into both image analysis platforms for production of reference data sets and laboratory information systems for daily pathology practices.

Simultaneous Determination of Antimalarial Agents by LC-MS/MS and Its Application to Evaluation of Fixed-Dose Tablets

We developed and validated a liquid chromatography tandem mass spectrometry (LC-MS/MS) method to quantify the antimalarials artesunate (ARS) and mefloquine (MFQ) in fixed-dose tablets. The detection was performed by a triple-quadrupole mass spectrometer in multiple reaction monitoring (MRM) in positive ion mode via electrospray ionization. Chromatographic separation was achieved with an XBridge C18 column (50 × 2.1 mm, 5 μm), using isocratic elution (350 μL min-1) of water/acetonitrile/methanol (30:35:35, v/v/v) containing 0.1% formic acid. The method was validated according to the International Conference of Harmonization (ICH) guidelines. The calibration curves obtained for ARS (400 to 600 ng mL-1) and MFQ (800 to 1200 ng mL-1) showed good linearity (r2 > 0.99), precision (relative standard deviation (RSD): ARS < 2.0%; MFQ < 1.9%), and accuracy (recoveries: ARS, 102.4-103.4%; MFQ, 97.4-101.6%), and were stable for 24 h at 8 oC. The method was successfully applied to commercial tablets, and recoveries of 98.7 ± 4.7% (ARS) and 105.6 ± 3.13% (MFQ). The method developed is a reliable alternative for public quality inspection control with the advantage of tandem mass specificity and speed.

Analytical Determination of Vitamin B12 Content in Infant and Toddler Milk Formulas by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS).

The development of a sample preparation method and optimization of the analytical instrumentation conditions were performed for the determination of the vitamin B12 content in emulsified baby foods sold on the Korea market. After removal of the milk protein and fats by chloroform extraction and centrifugation, the vitamin B12 was water extracted from the sample. Following filtration of the solution through a nylon filter, the water-soluble extract was purified by solid-phase extraction using a Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). The solution eluted from the cartridge was dried under a stream of nitrogen gas and reconstituted with 1 mL of water. The sample solution was injected into an LC-MS/MS system after optimizing the mobile phase for vitamin B12 detection. The calibration curve showed good linearity with the coefficient of correlation (r2) value of 0.9999. The limit of detection was 0.03 µg/L and the limit of quantitation was 0.1 µg/L. The method of detection limit was 0.02 µg/kg. The vitamin B12 recovery from a spiking test was 99.62% for infant formula and 99.46% for cereal-based baby food. The sample preparation method developed in this study would be appropriate for the rapid determination of the vitamin B12 content in infant formula and baby foods with emulsified milk characteristics. The ability to obtain stable results more quickly and efficiently would also allow governments to exercise a more extensive quality control inspection and monitoring of products expected to contain vitamin B12. This method could be implemented in laboratories that require time and labor saving.

Bovine mastitis prevalence and associated risk factors in dairy cows in Nyagatare District, Rwanda.

In response to farmer requests after milk from their herds was rejected by processors due to poor quality, a study was carried out from April to October 2011 to determine the prevalence of subclinical mastitis, associated risk factors and causative micro-organisms. Samples were collected from 195 dairy cows on 23 randomly selected dairy farms delivering milk to Isangano, Kirebe and Nyagatare milk collection centres in Nyagatare District, Rwanda. The Draminsk® Mastitis Detector was used to detect subclinical mastitis in individual cows based on milk electrical conductivity changes. Risk factors for mastitis that were evaluated included teat-end condition, cow dirtiness, breed, parity, age and stage of lactation. Relationships of these factors with mastitis status were determined using Chi-square analysis, and relative importance as causes of mastitis was assessed using logistic regression. Samples from 16 subclinical mastitis positive dairy cows were analysed to identify causative micro-organisms using Dairy Quality Control Inspection analytical kits. Subclinical mastitis prevalence was 52% across the farms. It was higher with increases in, amongst other risk factors, teat-end damage severity, cow dirtiness, and level of pure dairy breed genetics. The risk factors considered accounted for 62% of mastitis prevalence; teat-end condition alone accounted for 30%. Most of the mastitis cases (87.5%) were caused by coliform bacteria. Considering that farmers are upgrading their local Ankole cows to cross-breed dairy cows that are more susceptible to mastitis, results from this study indicate the need to dip the teats of cows in sanitisers, improve cow hygiene, and introduce mastitis prevention and control programmes.