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An assembly line is a sequence of workstations, connected together by a material handling system, which is used to assemble components into a final product. The economic importance of assembly as a manufacturing process has led to extensive efforts for designing an assembly line to ensure efficiency and cost effectiveness of assembly operations. These efficiency and effectiveness can be maximized by minimizing balancing loss and system loss. The current work offers a range based measure for System loss and describes a technique for jointly minimizing balancing loss and system loss. To arrive at the optimum solution of the joint minimization problem, the same has been reduced to sequential marginal minimization problems and simulation technique has been installed for obtaining the optimal solution. For demonstration purpose, one example has been worked out to indicate the strength of the suggested method.

The objective of the present work is to diminish the total process time (Makespan) and to increase the machine process time, by diminishing the idle time in a job-shop environment. Through the design of a hyper-heuristic based on an ant colony and genetic algorithms. This work is developed in two phases: in the first phase, a hyper-heuristic identification and definition is carried out for sequencing processes in job shop environments. In the second phase, the system effectiveness in the traditional production programming is shown. In the investigation project, an enterprise from the metal mechanic sector was chosen, where by means of a combination of an ant colony and genetic algorithms, the optimal route for an order is scheduled, achieving the optimization or suboptimization of its respective total process time in an upper percentage of 95%.El objetivo del presente trabajo es disminuir el tiempo de proceso (Makespan) e incrementar el tiempo de trabajo de las maquinas, diminuyendo el tiempo de ocio en ambientes de Job Shop, a través del diseño de una Hiper-heurística basada en colonia de hormigas y algoritmos genéticos. Este trabajo se desarrolla en dos etapas: en la primera se realiza la definición e identificación de una Hiper-heurística para la secuenciación de procesos en ambientes Job shop. En la segunda etapa, es mostrada la efectividad del sistema en la programación de la producción. En el proyecto de investigación, se seleccionó una empresa del sector metalmecánico, donde por medio de una combinación de colonia de hormigas y algoritmos genéticos, se programa la ruta óptima para un pedido, logrando la optimización o suboptimización de su respectivo tiempo total de proceso en un porcentaje superior al 95%.

Estudaram-se os efeitos da substituição na dieta da silagem de milho por silagem de girassol (0, 33 e 66% MS) no comportamento ingestivo de novilhos em confinamento. Utilizaram-se nove novilhos castrados com peso vivo e idade média inicial de 288 kg e 20 meses, respectivamente, pertencentes aos grupos genéticos Nelore, 21/32Charolês (C) 11/32Nelore (N) e 21/32N 11/32C. O delineamento experimental utilizado foi o de blocos ao acaso, com três repetições por tratamento. As dietas testadas foram: 100 % de silagem de milho e 0 % de silagem de girassol; 70,94% de silagem de milho e 29,06 % de silagem de girassol; 38,27 % de silagem de milho e 61,73 % de silagem de girassol, todas com relação volumoso:concentrado 60:40. O tempo destinado ao ócio deitado foi maior para os novilhos que consumiram apenas silagem de milho como volumoso em relação aos que consumiram silagem de girassol. O tempo despendido em ócio em pé foi semelhante entre as dietas com 33 (1,84 hora) e 66 % de silagem de girassol (1,96 hora) e menor para aquela sem silagem de girassol (1,62 hora). O tempo em ruminação dos animais aumentou com a inclusão da silagem de girassol na dieta e correspondeu a 8,61; 8,76 e 9,45 horas, respectivamente, para 0; 33 e 66 % de silagem de girassol. Animais alimentados somente com silagem de milho apresentam maior eficiência de ruminação da matéria seca e da fibra em detergente neutro. O tempo despendido por refeição diminui com o aumento da participação da silagem de girassol.The objective of this experiment was to evaluate the effect of replacing corn silage with sunflower silage (0, 33 e 66% DM) on the ingestive behavior of fedlot steers. Nine castrated steers were used, with average 288 kg initial live weight and 20 month old from the Nellore (N), 21/32Charolais (C) 11/32N and 21/32N 11/32C genetic groups. A randomized complete block experimental design was used, with three replications per treatment. The tested diets were: 100% corn silage and 0% sunflower silage; 70.94% corn silage and 29.06% sunflower silage and 38.27% corn silage and 61.73% sunflower silage, all with a 60:40 roughage:concentrate ratio. Time spent lying idle was greater for steers that consumed only corn silage as roughage compared to those that consumed sunflower silage. Time spent standing idle was similar between 33 (1.84 h) and 66% sunflower silage (1.96 h) and lower for 0% sunflower silage (1.62 h). The animals rumination time increased with the inclusion of sunflower on diet, with values of 8.61; 8.76 and 9.45 h, respectively for 0; 33 and 66% sunflower silage. Animals fed only with corn silage show better dry matter and neutral detergent fiber rumination efficiencies. The time spent feeding decrease with higher participation of sunflower silage.

In this paper, we analyzed the sequencing situations on two machines where the machinesetup time is not independent of processing order.A real case study of Hadhramout Industrial Company Complex, Mukalla, Yemen is takenas a model. Data is collected and analyzed using MS-Excel by different methods. The problemformulation has been presented. Multiple solutions were obtained by applying sequencingmethods. The comparison of different solutions is done to choose the optimal solution. Thetime is reduced by 23% to perform the group of jobs and the setup time is reduced 30.5% aswell as the mean flow time is reduced by 30.5%.

from raw materials and semi productspass through many tasks, these tasks differ in numbers and complexity with the productdifferece, design specifications, and also the production system type. Tasks timedifferential cause work in process inventory problem or idle time problem in someworkstations of the line. These problems affect efficiency of the line and increase thetotal production cost. In this research, computer aided visual monitoring system designsand builds for monitoring the flow of materials and determine location and quantity ofwork in process inventory in the production line to minimize this problems by rearrangeworkstations of the line and connecting the critical stations that materials blocked in itwith extra stations in parallel to minimize the work in process inventory amongworkstations of the line possiblely to minimum level to increase the flow of materialsand then to the increases efficiency of the line .The suggested system applied at the statecompany for electrical industries on the stator production line where the system uses formonitoring & studying flow of materials between its workstations. The researcherdepends on company data&his grouping data. Monitoring &studying the currentworkstations arrangement shows low efficiency (50.96%) and low daily production rate(270 unite/day), so arrange workstations of the line by suggested arrangement, canincrease the line efficiency to (77.96%)and also can increase daily production rate to(540unite/day) by arrange the line workstations by suggested arrange

In this paper, we have developed an integrated supplier-manufacturer-retailer, joint economic lot-sizing model for the items with stochastic demand and imperfect quality. The supplier produces the item (raw material) up to certain time, which is a decision variable, and sends it to the manufacturer. Now, the manufacturer produces the item in small cycles and the production process of manufacturer is imperfect which produces certain number of defective items. A 100 % screening process for detecting the imperfect quality items is conducted, and at the end of each cycle, the imperfect items are accumulated and are reworked by the manufacturer. Thus, ultimately the retailer receives the perfect quality item. We consider that the delivery quantity to the retailer depends on the price and stock-dependent stochastic demand of the retailer. The model considers the impact of business strategies such as optimal time, optimal ordering size of raw material, production rate, etc. in different sectors on collaborating marketing system. An analytical method is applied to optimize the production time and production rate to obtain minimum total cost. Finally, numerical results, which have several interesting managerial insights and implications, and the sensitivity analysis are presented and discussed for illustrative purposes. [ABSTRACT FROM AUTHOR]

A new heuristic based on the Nawaz–Enscore–Ham algorithm is proposed in this article for solving a permutation flow-shop scheduling problem. A new priority rule is proposed by accounting for the average, mean absolute deviation, skewness and kurtosis, in order to fully describe the distribution style of processing times. A new tie-breaking rule is also introduced for achieving effective job insertion with the objective of minimizing both makespan and machine idle time. Statistical tests illustrate better solution quality of the proposed algorithm compared to existing benchmark heuristics. [ABSTRACT FROM AUTHOR]