scholarly journals Measuring the Performance of an Eigenvalue Control Chart for Monitoring Multivariate Process Variability

Author(s):  
Aishah Mohd Noor ◽  
Maman Abdurachman Djauhari

In manufacturing process, it is very important to control and monitor the stability of a process such that a high quality product will be produced. The most common statistical tool used for monitoring the stability of a process is the control chart. In recent applications of control charting methods, there is a need to construct a control chart that is able to represent the behaviour of a multivariate process since in many manufacturing processes; quality of a product is determined by the joint-level of several quality characteristics. For this reason, in this paper, a new control chart is introduced for monitoring the stability of multivariate process in terms of the process variability. The proposed method is based on charting each of the eigenvalues of a covariance matrix. To show the efficiency of the proposed method, we conduct a simulation study and compare the performance of the proposed method with the existing method. A real example will be presented to illustrate the advantage of our proposed method.

Author(s):  
N.A. Jurk ◽  

The article presents scientific research in the field of statistical controllability of the food production process using the example of bakery products for a certain time interval using statistical methods of quality management. During quality control of finished products, defects in bakery products were identified, while the initial data were recorded in the developed form of a checklist for registering defects. It has been established that the most common defect is packaging leakage. For the subsequent statistical assessment of the stability of the production process and further analysis of the causes of the identified defect, a Shewhart control chart (p-card by an alternative feature) was used, which allows you to control the quality of manufactured products by the number of defects detected. Analyzing the control chart, it was concluded that studied process is conditionally stable, and the emerging defects are random. At the last stage of the research, the Ishikawa causal diagram was used, developed using the 6M mnemonic technique, in order to identify the most significant causes that affect the occurrence of the considered defect in bakery products. A more detailed study will allow the enterprise to produce food products that meet the established requirements.


2021 ◽  
Vol 30 (6) ◽  
pp. 50-55
Author(s):  
S.V. Borisova ◽  
◽  
N.U. Mukhametchina ◽  
G.S. Sagdeeva ◽  
◽  
...  

The results of the study of the influence of various concentrations of the complex bakery improver «Unipan Total» on the properties of semi-finished products and quality indicators of bakery products are presented. Bakery products were produced using the unpaired method according to a unified recipe for Dniprovskaya buns. To obtain a high-quality product, prototypes were prepared from wheat bakery flour of the highest grade with the addition of the «Unipan Total» improver at a concentration of 0,5 to 8% to the flour weight, control ones without the improver. Organoleptic and physicochemical indicators of the quality of wheat bread samples were determined by conventional methods.


2017 ◽  
Author(s):  
Besse Helmi Mustawinar ◽  
Nurtiti Sunusi ◽  
Erna Tri Herdiani

Meso ◽  
2021 ◽  
Vol 23 (6) ◽  
pp. 483-496
Author(s):  
Linda Martić Kuran ◽  
Jelena Đugum ◽  
Marina Krvavica ◽  
Marijana Drinovac Topalović

The protection of Dalmatian lamb ("Dalmatinska janjetina") with a protected designation of origin label (PDO) is based on the specific quality of meat of Dalmatian pramenka lamb and the traditional lamb breeding method in the geographic area that coincides with the breeding area of Dalmatian pramenka (indigenous Croatian sheep breed). Under the name of "Dalmatinska janjetina", only the meat of lambs of Dalmatian pramenka, bred exclusively in Dalmatia, can be placed on the market. In the process of obtaining a PDO label, which has recently been completed at the Croatian national level and is currently in the process at the EU level, a survey among Croatian consumers (a sample of 1,034 consumers from all over Croatia) was conducted to determine the recognition of this product on the Croatian market, as well as consumer preferences considering similar products from other Croatian regions. The research has shown that Croatian consumers recognize Dalmatian lamb as a traditional, high-quality product. Thus, almost 75 % of the respondents recognize it as a particular type of lamb of better quality than others on the Croatian market. Almost 85 % of the respondents use lamb regardless of type in their diet, but more than 58 % always on special occasions (folk festivals and family celebrations), especially if prepared in the traditional way (lamb on a spit) by which Dalmatia as a region is recognized by more than 85 % of the respondents. The market reputation and connection with the geographic production area are why Croatian consumers rather buy Dalmatian lamb over others.


2021 ◽  
Vol 9 (5) ◽  
pp. 602-606
Author(s):  
Suruchi Malik ◽  
◽  
Kirti Sharma ◽  
Anil Kanaujia ◽  
◽  
...  

The instant rising demand of plant-based drugs is unfortunately creating heavy pressure on some selected high-value medicinal plant population in the wild. The safety, quality and efficacy of these products have become a major concern for health authorities and the consumers. Unavailability of proper production technology and suitable area of cultivation, post-harvest processing, market constraints and low economic returns as compared to major cereal crops, are the main problems in cultivation of these herbs and spices. Safe, efficacious and a high-quality product showing batch to batch consistency can be maintained by following harvesting and post harvesting standard guidelines for MAPs (Medicinal & Aromatic Plants).


2021 ◽  
pp. 16-19
Author(s):  
Мунира Фадитовна Ямалетдинова

В данной статье автором исследован процесс тепловой обработки абрикосовых косточек нетрадиционным способом в СВЧ-печи для производства национального продукта - соленых косточек. Технология производства соленых косточек включает следующие технологические процессы: образование трещины на скорлупе абрикосовой косточки, замачивание косточек в солевом растворе, жарение, охлаждение естественным путем, реализация. Самым важным процессом при этом является тепловая обработка (жарение косточек), так как качество получаемого готового продукта - соленых косточек - будет зависеть от количества получаемой косточкой теплоты. Предлагаемый автором способ тепловой обработки в СВЧ-печи базируется на явлении дипольного момента, основанного на смещении зарядов и связанных с ними молекул при воздействии на продукт переменного электромагнитного поля. Обрабатывая косточки в течение 60-90 сек в СВЧ-печи, образуется трещина на стыке скорлупы за счет того, что энергия в СВЧ-печах очень высока, внутри косточки температура резко увеличивается, происходит кипение влаги и парообразование, за счет этого повышается давление - и скорлупа на стыке косточки дает трещину. Получены результаты изменения температуры косточек в СВЧ-печи, в которой осуществляют тепловую обработку. На основе полученных экспериментальных данных построены графики изменения температуры абрикосовых косточек различных сортов. При этом продолжительность тепловой обработки сократилась и значения температуры не превышали 165 °С, что обеспечивает равномерность распределения температуры по объему косточки и дает возможность получить продукт высокого качества и сохранение питательных веществ соленых косточек. In this article, the author studies the process of heat treatment of apricot seeds in an unconventional way in a microwave oven, for the production of the national product of salted seeds. The technology of production of salted seeds from apricot seeds includes the following technological processes: the formation of a crack on the shell of the stone; soaking in a saline solution of the seeds; frying; cooling naturally; selling. The most important process in this case is the process of heat treatment (roasting the seeds), since the quality of the ready product of salted seeds will depend on the amount of heat received by the seed. The proposed method of heat treatment in a microwave oven is based on the phenomenon of the dipole moment, based on the displacement of charges and associated molecules when the product is exposed to an alternating electromagnetic field. Processing the seeds for 60-90 seconds in a microwave oven, a crack is formed at the junction of the shell due to the fact that the energy in microwave ovens is very high, the temperature inside the seed increases sharply, water boils and vaporization occurs, due to this, the pressure increases and the shell at the junction of the seed cracks. The results of the change in the temperature of the seeds in the microwave oven, in which the heat treatment is carried out, are obtained. Based on the obtained experimental data, graphs of temperature changes in apricot seeds of varieties are constructed. At the same time, the duration of heat treatment was reduced and the temperature values did not exceed 165 °C, which ensures a proportion of temperature distribution over the volume of the seed and makes it possible to obtain a high-quality product and preserve the nutrients of salted seeds.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Alexander N. Ostrikov ◽  
Abdymanap A. Ospanov ◽  
Alexander А. Shevtsov ◽  
Nurzhan Zh. Muslimov ◽  
Aigul K. Timurbekova ◽  
...  

AbstractThe drying procedure is a key to producing pasta of intended quality and with a specific price tag. However, the existing models are mainly to describe the drying process in a steady state. A mathematical model of tube-shaped pasta drying in a conveyor belt dryer with a stepwise heating supply allows determining the curve of temperature and moisture gradients for a tube-shaped pasta unit. It also helps select the best settings to minimize the heat-power costs while maintaining the good quality of a dried product. The given model describes the drying process in a true-to-life form and ensures the convergence of calculations to observations (deviation: 12.5%). The model was utilized to design a transient drying protocol for conveyor belt dryers with a stepwise heating supply. The proposed dryer has high service reliability and produces uniformly dried high-quality product.


2006 ◽  
Vol 35 (2) ◽  
pp. 276-284 ◽  
Author(s):  
Dragan Miljkovic ◽  
Hyun Jin

The case of reduction in ad valorem tariffs as a trade liberalization policy is considered in this article. It is shown that the reduction leads to a higher quality of imports, ceteris paribus. This hypothesis was tested on the case of Japanese beef imports from the United States and Australia. U. S. beef, according to the results of Gallup surveys, is considered by Japanese consumers to be a high quality product, while Australian beef is considered to be a low quality product. Empirical results support the hypothesis. Moreover, the recent domination of U. S. beef in the Japanese market is further explained by increasingly more efficient U. S. beef production relative to Australian production and a strong income effect, where an increase in per capita income leads to more demand for higher quality products.


Author(s):  
Umar Abubakar Adamu ◽  
Gulumbe Shehu Usman ◽  
Dikko Hussaini Garba

Recently, much attention has been raised on effects of high increase in drugs counterfeiting and sub-standard quality which leads to many casualties in Nigeria. The Multivariate Statistical Process Control Charts approach was employed to examine such defects especially in assessing the official physico-chemical quality of chloroquine phosphate tablet (BP250mg) which claimed to contain the required quality properties. The Multivariate Exponentially Weighted Moving Average (MEWMA) Control Chart gives a powerful and reliable control chart than the widely used Hotelling’s T2˗Control Chart, which detects the smallest shift in the product process means and have minimum process variability. Also, the Matrix of scatter plots indicated the existence of relationship among the process variables and the Principal Component Analysis (PCA) minimized the rate of dimensionality of the process variability, which captured most of the variables outliers and retained the first Principal Components (PC) that explained over 99% variability of the product. To this end, the study results shows that the product quality characteristics (process variables) is under control (stable) and conform to international standard as specified by BP 2002.


2008 ◽  
Vol 3 (3) ◽  
Author(s):  
Melissa Toifl ◽  
Clare Diaper ◽  
Roger O'Halloran

A comparison of chemical versus biological package greywater treatment systems was undertaken using a new laboratory based protocol that included a synthetic greywater formulation that mimics average bathroom and laundry greywater in Australia. The results for chemical, nutrient and metals removal showed that the treatment systems behaved very differently under the test conditions. The chemical system was able to remove most of the components of greywater that could be detrimental to the environment and produced high quality product water. The biological system was only able to remove some of the components of the greywater, and did not produce the same quality of product water. However, the product water quality was found to improve continually over the duration of testing. It was concluded that for the current composition of Australian greywater the chemical based technology produced the highest quality product but that other environmental costs, such as chemical use and energy also need to be assessed. If greywater compositions change with the use of more biodegradable, low environmental impact personal care and cleaning products, biological treatment systems may be better suited to treating greywater in the future.


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