scholarly journals A Model for Determining the Effect of Irregular Power Supply on Machining Foundry Products in a Developing Economy

2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Adebayo F Owa ◽  
Fisayo Adesina ◽  
Funso O Kolawole ◽  
Oluwole D Adigun ◽  
Biliaminu Kareem

In this paper, profit is maximized (or production cost is minimized) by developing an Integer programming (IP) model to determine, at a given respective unit cost, optimal numbers of outputs obtainable per production cycle (time) using public electricity generated from national grids and alternate electricity from generators subject to production output capacity or demand constraint. The results obtained showed that production cycle time has a great impact on the determination of optimal outputs for the respective conditions. Also, increase in cost of public electricity per unit product has an upper limit beyond which it has negative effect on the profitability. The results served as determinant factors for production industry in establishing the level of outputs that sustained the profitability by providing optimal cost of public electricity to operate without having any effect on the profit, at a given cycle time. Keywords— Constraint, cycle time, integer programming, optimal number, model

2020 ◽  
Vol 5 (2) ◽  
Author(s):  
Adebayo F Owa ◽  
Fisayo Adesina ◽  
Olawale O Ajibola

Computer aided models such as Dynamic, Quadratic, and Integer programming have been developed to solve production challenges relating to Manpower, Inventory and Maintenance assuming constant and regular power supply, which is a hard condition to meet in a developing country like Nigeria where power supply is irregular. This paper developed a Computer aided model to address this challenge using Integer programming (IP), by considering profit (Z) as a function of cost and revenue of a machined foundry product. Software was developed to serve as database and the same time analyzed complex mixed – model system where parallel workstation, shift or batch production is allowed. The software was designed to have graphic user interface (GUI), which enable the user to input data like values of product code (identification number for each product), capacity of machine, established unit cost of production, production cycle time, selling cost and the unit cost of production to determine the impact when electricity power from national grid is used, as opposed to  fueling a  diesel-engine generator, for machining foundry products. Costs and production capacity data were collected from Ruthade Foundry Engineering Services, Akure, Ondo State, to validate the model. The results revealed that output per unit time is higher when power from national grid is holistically utilized than when power from generator was used for machining foundry product.  The results serve as genuine guiding tool for foundry operators in selecting a particular course of action on electricity utilization during production and enhance sustainability of production industry. Keywords— Constraint, cycle time, integer programming, Microsoft Visual Basic, model, optimal number


2014 ◽  
Vol 38 (3) ◽  
pp. 289-304
Author(s):  
Dragan Ćoćkalo ◽  
Sanja Stanisavljev ◽  
Dejan Đorđević ◽  
Milivoj Klarin ◽  
Aleksandar Đ. Brkić

A model for the stochastic determination of the elements of production cycle time is proposed and experimentally verified in this survey. The originality of the model as reflected in the idea of using a work sampling model to monitor the production cycle is one of the most significant indicators of production effectiveness and efficiency, instead of applying classical methods. It has been experimentally proved that for a corresponding representative set the elements of working time range according to normal distribution law and that, dynamically viewed, it is possible to use mean value calculations to establish control limits on three standard deviations for the individual elements of working time and thus to master the process. Based on our experimental investigations, it has been proved that in the practice of small and medium-sized enterprises with serial production it is possible to design and apply a very simple but accurate enough stochastic model to determine the elements of working cycle time and in this way optimize the duration of production cycle time.


Author(s):  
N. N. Loy ◽  
S. N. Gulina

The effect of presowing seed treatment on various concentrations of dicarboxylic (organic) acids on the sowing characteristics of spring barley has been studied. Seeds were treated with organic acids obtained by exposing cuttings to the radiation with a dose of 100 kGy and consequent hydrolysis, in concentrations: 1•10-7 %; 1•10-9; 1•10-11; 1•10-13 and 1•10-15 % on a laboratory rotary machine RVO-64 for one day before laying for germination. Distilled water was used for the control case. The rate of application of the working solution calculated as 10 liters / ton of seeds. Seeds were germinated in filter paper rolls in accordance with GOST 12038-84 requirements. The temperature was maintained at +24 ° C in the thermostat where the glasses with rolls were placed. For determination of germinative power and laboratory germination the sprouted seeds were evaluated after three and seven days, respectively. In laboratory experiments it was established that the treatment of barley seeds of varieties Zazersky 85, Nur and Vladimir with organic acids (OK) in different concentrations had both a stimulating and a negative effect. On the Zazersky 85 variety, in variants with acid concentrations of 1•10-9 and 1•10-11, an increase in germination energy (EP) by 2-4% and a significant decrease (by 3-4%) of laboratory germination (LV) of barley seeds were noted. On the Nur variety, the increase in EP was observed at 4% (concentration 1•10-11), LV and seed growth force (CPC) by 2-7% at a concentration of 1•10-7 and in the dose range 1•10-11 - 1•10-14 compared to the control values. On the grade of Vladimir, an increase in EP, LV, and CPC was found to increase by 1-6% at concentrations OK 1•10-7 and 1•10-13. It was shown that the treatment of seeds with acids led to an increase in the length of the germ in all studied varieties (by 3-9%) and dry biomass of 7-day-old seedlings - by 3-6%. Consequently, the treatment of seeds with a mixture of dicarboxylic acids has a stimulating effect on the sowing quality of spring barley.


Author(s):  
Nita Shah ◽  
Ekta Patel ◽  
Kavita Rabari

Aims: This article analyzes an inventory system for deteriorating items. The demand is quadratic function of time and is dependent on time, price and advertisement. Shortages are allowed and partially backlogged. Background: Demand and pricing are the two most crucial factors in inventory policy for any business to be successful. In today’s era of competitive circumstances, any product is promoted through advertisement, which plays a vital role in changing the demand pattern among the community. The marketing and demonstration of an item by time-to-time with fashionable advertisements through well-known media such as TV, radio, newspaper, magazine, etc. However, this idea is not always true for some goods like wheat, vegetables, fruits, food grains, medicines and other perishable goods due to their deteriorating nature and this in turn decreases demand for such goods. Deterioration may define as decay, damage, spoilage, evaporation, obsolescence, pilferage. Hence, deterioration effect is a major part in inventory control theory. So in this article demand rate is considered to be a function of selling price, time and occurrence of advertisement instantaneously. Objective: A solution procedure is obtained to find optimal number of price changes and optimal selling price to maximize the total profit. Method: Classical Optimization. Result: From the sensitivity analysis table, it can be seen that the optimal profit is highly sensible to advertisement coefficient and purchase cost. With an increment in rate of deterioration, selling price decreases. Scale demand has reasonable effect on cycle time and selling price. When the value of increase, the cycle length and profit goes on decreasing. Growth in profit is observed if we increase parameter b, higher will be the profit. Price elasticity is sensible parameter with respect to selling price. If backlogging rate increases, the profit will decreases. The inventory parameters holding cost, back order cost and lost sale cost have marginal effect on total profit. Conclusion: In this article, an inventory model is proposed for deteriorating items with variable demand depends upon the advertisement, selling price of the item and time. Shortages are allowed and partially backlogged and backlogging rate depends on the waiting time for the next replenishment. From this article, we can conclude that the parameters are insensible with respect to optimal profit, cycle time and selling price and rest of the parameters have practical output on total profit.


Machines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 141
Author(s):  
F. J. G. Silva ◽  
M. R. Soares ◽  
L. P. Ferreira ◽  
A. C. Alves ◽  
M. Brito ◽  
...  

The structure of car seats is becoming increasingly complex, with mixing of wire conformation and plastic injection. The plastic over-molding process implies some labor, which can be reduced if novel solutions are applied in this manufacturing area. The handling of the wires used in car seats is the main problem identified in the process, wasting time both in the feeding and in the extraction of the molds used in the wire over-molding process. However, these machines are usually extremely compact and the free space around them is too short. In classic molding injection machines, there are just two half-molds, the female, and the male. In the over-molding process of wires used in car seats, three half-molds are used in order to increase the cycle time. Thus, to solve this problem, the classic robotic solutions are not appliable due to lack of space and elevated cost. This work describes the development of an automated solution able to handle the wires in both the feeding and the extracting phases of the production cycle, avoiding the traditional labor costs associated with this type of machine. Departing from an industrial need, the developed novel solution is described in detail and can be successfully adapted to other situations of low added-value products where it is needed to increase the productivity and competitiveness of the product. The system developed uses mechanical and pneumatic solutions which, combined, can be used to solve the identified problem, occupying a restricted space and requiring a small budget. This solution can be translated into guidelines that will allow the analysis of situations where the same system can be applied.


2017 ◽  
Vol 8 (2) ◽  
pp. 331-350
Author(s):  
Aulia Afridzal ◽  
Helminsyah ◽  
Yusrawati JR Simatupang

This study tested the influence of accountability audit, knowledge and motivation to the quality of the work of the internal auditor. The respondents in this study is the auditor of the Inspektorat Pemerintah Kabupaten Aceh Besar and Kota Banda Aceh. The number of Auditors in this study as many as 37 Auditors. Method of determination of the sample used in this study was the census, while the method of data processing by means of multiple linear regression. The results of this research show that the whole variable (accountability, audit and motivation knowledge) together positive effect to the quality of the work of Auditors. Partially negative effect accountability to the quality of the work of Auditors, audit knowledge and motivation of the positive effect of the quality of the work of Auditors. This is shown by the value of R2 of 0.129 or 12.9%. This tells us that the variable accountability audit, knowledge and motivation affects the variable quality of the work the auditor amounted to 12.9%, while the rest of 87.1% are affected by other factors which are not formulated in the model study These.   Abstrak Penelitian ini menguji pengaruh akuntabilitas, pengetahuan audit dan motivasi terhadap kualitas hasil kerja auditor internal. Responden dalam penelitian ini adalah para auditor yang bekerja pada Inspektorat Pemerintah Kabupaten Aceh Besar dan Kota Banda Aceh. Jumlah auditor dalam penelitian ini sebanyak 37 auditor. Metode penentuan sampel yang digunakan dalam penelitian ini adalah sensus, sedangkan metode pengolahan data dengan cara regresi linear berganda. Hasil penelitian ini menunjukkan bahwa seluruh variabel (akuntabilitas, pengetahuan audit dan motivasi) secara bersama-sama berpengaruh positif terhadap kualitas hasil kerja auditor. Secara parsial akuntabilitas berpengaruh negatif terhadap kualitas hasil kerja auditor, pengetahuan audit dan motivasi berpengaruh positif terhadap kualitas hasil kerja auditor. Hal ini ditunjukkan oleh nilai R2 sebesar 0,129 atau 12,9%. Ini menjelaskan bahwa variabel akuntabilitas, pengetahuan audit dan motivasi mempengaruhi variabel kualitas hasil kerja auditor sebesar 12,9%, sedangkan sisanya sebesar 87,1% dipengaruhi oleh faktor-faktor lainnya yang tidak dirumuskan dalam model kajian ini. Kata kunci: Akuntabilitas, Pengetahuan Audit, Motivasi dan Kualitas Hasil Kerjaauditor


2018 ◽  
Vol 9 (1) ◽  
pp. 63
Author(s):  
Riza Aulia Fitri ◽  
Agus Munandar

This research aimed to examine the influence of Corporate Social Responsibility (CSR), profitability, and leverage toward tax aggressiveness by considering the size of the company as the moderating variable. The population was 111 companies listed on the Indonesian Stock Exchange (BEI) from 2010 to 2015. Determination of the sample used purposive sampling method, and it obtained a sample of 36 manufacturing based on certain criteria. The analysis technique used was the multiple regression analysis. The results show that CSR and leverage have a significant and negative effect influence on the tax aggressiveness of the corporate tax. Meanwhile, profitability does not significantly influence the tax aggressiveness in corporate taxes, and the size of company cannot moderate the influence of CSR, the profitability, and leverage on tax aggressiveness.


Author(s):  
Silvana POPESCU ◽  
Cristin BORDA ◽  
Cristina EL MAHDY ◽  
Eva Andrea LAZAR ◽  
Anamaria BLAGA PETREAN ◽  
...  

The aim of this work was the investigation of the effect of bedding type on the airborne concentration of bacteria and fungi in broiler houses. The study was performed in two commercial farms (A and B) with different bedding (chopped straw in farm A, sunflower seed hulls in farm B). The determination of the bacteria and fungi’s numbers was performed in the first and the sixth weeks of the production cycle. Both the concentration of the bacteria and fungi showed higher values in the farm A compared with the farm B, especially in the latter period of the production cycle. In both farms, significant differences (P < 0.05) were recorded between the two periods of the determinations. The results of this study suggest that using sunflower seed hulls as bedding leads to lower levels of microbial contamination of the air in broiler houses, comparing with the use of chopped straw.


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