Assembly Teams Research Articles

Research of unit train loading technologies at the sidings of grain elevators with their shunting locomotives

The purpose of the study is to increase the unit train load efficiency at the elevators having their shunting locomotives. The research is based on the analysis of time series, methods of organizing the operational work of railways, and methods of traction calculations. The paper considers the problem of organizing shunting work at elevators when loading grain unit trains. Critical wear and tear of shunting locomotives in railway transport of general use necessitates using their locomotives at the elevators. As a result of the research, the dependence of the duration of shunting and cargo operations on the number of cars in the unit train and on other factors was established. Various types of shunting locomotives were compared. Based on the analysis, it was established that it is advisable to use four-axle shunting diesel locomotives with hydraulic transmission for shunting work at the elevators. The traction force of such locomotives is sufficient to deliver empty cars to the elevator at a speed of 14–15 km/h. Loaded cars can be removed at a speed of 14–15 km/h with a slope of the connecting track up to 2–5 ‰. With greater slopes, the removal of loaded cars should be performed at a speed of 5 km/h. The main factor affecting the duration of shunting operations is the distance of delivery and removal of cars. Technologies for loading the grain unit trains at the elevators, providing for the presence of cars at the loading stations for two and three days, have also been developed. The main factor affecting the duration of unit train loading is the staff of locomotive assembly teams. The originality of the study is in obtaining the dependence between the parameters of the technical support of the elevators and the duration of the presence of cars in the connecting station – elevator’s siding system. The practical value of the paper is that its results can be used in the design of the reconstruction of existing and construction of new elevators, as well as in the estimation of costs associated with various loading technologies of the unit trains for the corresponding sidings.

ESTIMATIVA DE PRODUTIVIDADE NO LANÇAMENTO DE CONDUTORES ELÉTRICOS ATRAVÉS DE SIMULAÇÃO COM OS MÉTODOS DE MONTE CARLO E HIPERCUBO LATINO

This article proposes to analyze the feasibility of using the Monte Carlo and Latin Hypercube methods to estimate Global Productivity in the process of installing electrical conductors of different diameters based on small samples. The study was conducted using data collected during the Construction and Assembly phase in two Industrial Plants, located in the cities of Três Lagoas-MS (Brazil) and HuachipaLima (Peru). Random samples were selected from information obtained directly from the construction and assembly teams of the construction company, with 10, 15, and 20 elements, respectively. These samples were processed through simulation using the @Risk6 software to assess the possibility of obtaining results similar to the field-collected data, both in Brazil and abroad. The results of the study demonstrate the feasibility of applying the simulation methods used in estimating productivity in conductor installation. This article presents a methodology that allows, through the development of probability curves, to support companies in decision-making regarding the studied process, with indices that may allow them to make adjustments to the project during, and not just at its conclusion.

Examining the Effects of Cognitive Assistive Agents on Team Coordination in Manufacturing Teams

This article details the motivation and design of an experiment to investigate the effects of artificially intelligent cognitive assistive agents on coordination efforts in manufacturing teams. As automation solutions become more accessible and products rapidly grow in complexity, there are significant calls to leverage abilities of both artificial agents and human workers to maximize team functioning and product output. As such, we propose an experimental design where we introduce a cognitive agent with two levels of autonomy (low, and high) into a team of participants during an assembly task. We hypothesized that cognitive assistive technologies would enhance coordination within assembly teams, leading to higher productivity and reduced errors, with initial data suggesting trends in support of these hypotheses. We seek to demonstrate the value of cognitive agents in augmenting human workers, allowing manufacturers to see the benefit of increased productivity while retaining value and relevance of human labor in the face of technological development.

Integrated optimization of production planning and scheduling in uncertain re-entrance environment for fixed-position assembly workshops

For the fixed-position assembly workshop, the integrated optimization problem of production planning and scheduling in the uncertain re-entrance environment is studied. Based on the situation of aircraft assembly workshops, the characteristics of fixed-position assembly workshop with uncertain re-entrance are abstracted. As the re-entrance repetition obeys some type of probability distribution, the expected value is used to describe the repetition, and a bi-level stochastic expected value programming model of integrated production planning and scheduling is constructed. Recursive expressions for start time and completion time of assembly classes and teams are confirmed. And the relation between the decision variable in the lower-level model of scheduling and the overtime and earliness of assembly classes and teams in the upper-level model of production planning is identified. Addressing the characteristics of bi-level programming model, an alternate iteration method based on Improved Genetic Algorithm (AI-IGA) is proposed to solve the models. Elite Genetic Algorithm (EGA) is introduced for the upper-level model of production planning, and Genetic Simulated Annealing Algorithm based on Stochastic Simulation Technique (SS-GSAA) is developed for the lower-level model of scheduling. Results from our experiments demonstrate that the proposed method is feasible for production planning and optimization of the fixed-position assembly workshop with uncertain re-entrance. And algorithm comparison verifies the effectiveness of the proposed algorithm.

An integrated website of electronic data interchange and computer-aided process planning in production outsourcing

The assembly industry implements production outsourcing to meet the needs of assembly product components. The outsourcing of assembly product components is based on a relationship model between the contractor and the industry, between the industry with assembly parts and other processes, and more recently between the assembly parts and sales. In production outsourcing, there are generally no communication patterns established between the contractor/supplier and the assembly team regarding problems that may appear during the assembly process. Electronic data interchange (EDI) technology as a method to promote electronic communication between companies can be implemented for assembly teams and suppliers so that the former can relay component assembly problems during the assembly process. In order to improve coordination and communication with external business partners, the production outsourcing activities need EDI technology so they can communicate rapidly and accurately. To make EDI technology more useful, this method can be integrated with a manufacturing, planning system called computer-aided process planning (CAPP). CAPP is a link between design and manufacturing in a computer-integrated manufacturing environment. Commonly used by manufacturing engineers, CAPP can be used to develop a product manufacturing plan. The purpose of the present study was to design and develop a web-based software application integration initiative between EDI and CAPP that can be used as a communication means between the assembly team and the supplier, which will specifically help the assembly team to plan component assembly process so they can eliminate or reduce manual intervention in assembly planning

Atomic Dysfunction

Following World War II the US believed its atomic monopoly was the primary tool to offset large, standing communist ground forces within the Soviet orbit. However, both the newly established and civilian-run Atomic Energy Commission (AEC) along with the nascent US Air Forces’ Strategic Air Command (SAC) were models of dysfunction. In the late 1940s neither the civilians nor the military were capable of fulfilling the requirements outlined in the envisioned atomic air offensives of the time. Apart from their internal problems, both the AEC and SAC failed to properly coordinate with each other for effective transfer of bomb material, requisite training, and standing up the required number of atomic ordnance assembly teams. As a result, the American atomic monopoly from 1945–1950 was largely a bluff with few men, materials, and resources to serve as the nation’s primary strategic offense.

Design and Engineering of a Target for X-Ray Thomson Scattering Measurements on Matter at Extreme Densities and Gigabar Pressures

Reconciling the experimental and system requirements during the development of a new target system is one of the most challenging tasks in the design and engineering of targets used in the National Ignition Facility.Targets for the GigaBar 3 campaign were meant to allow the detection of extremely weak Thomson scattering from matter at extreme densities in the face of very bright backlighter and laser entry hole plasma emissions. The problem was to shield the detector sufficiently while maintaining beamline and view clearances, and observing target mass restrictions.A new construction process, based on a rapid prototype frame structure, was used to develop this target. Details of the design process for these targets are described, and lessons from this development for production and target assembly teams are discussed.

Good ergonomics and team diversity reduce absenteeism and errors in car manufacturing

Prior research suggests that ergonomics work design and mixed teams (in age and gender) may compensate declines in certain abilities of ageing employees. This study investigates simultaneous effects of both team level factors on absenteeism and performance (error rates) over one year in a sample of 56 car assembly teams (N = 623). Results show that age was related to prolonged absenteeism and more mistakes in work planning, but not to overall performance. In comparison, high-physical workload was strongly associated with longer absenteeism and increased error rates. Furthermore, controlling for physical workload, age diversity was related to shorter absenteeism, and the presence of females in the team was associated with shorter absenteeism and better performance. In summary, this study suggests that both ergonomics work design and mixed team composition may compensate age-related productivity risks in manufacturing by maintaining the work ability of older employees and improving job quality.

I. The Interpolated Hispana and the Origins of Pseudo-Isidore

This article aims to resolve persistent questions about the date and early manuscript tradition of Pseudo-Isidore by investigating the relationship between the Pseudo-Isidorian collection and its most important formal source, long known to scholarship as the Hispana Gallica Augustodunensis, or the Autun Hispana. This investigation reveals that the Pseudo-Isidorian forgeries were assembled from a pre-existing collection of components - including the Autun Hispana and an early dossier of papal letter forgeries - on two occasions, by two distinct teams. At least some of these components were developed by Louis the Pious's opponents at Corbie, as Klaus Zechiel- Eckes has argued. Paschasius Radbertus was almost certainly involved at this early stage, which likely extended from the early to the later 830s. A series of distractions and setbacks, however - including Wala's exile to Bobbio after the failed coup in 834; Louis the Pious's own death in 840; and the subsequent Carolingian civil war from 840 to 843 - prevented any widespread use or circulation of the forgeries. lt was left to a later generation of scholars and legal theorists to blend the papal letter forgeries with the Autun Hispana, and, finally, to realize the full Pseudo- Isidorian collection. This was done by two distinct and largely independent assembly teams, working from a common pool of components, most probably during the pontificate of Nicholas I (858-867). The unusually diverse early manuscript tradition of the forgeries reflects these two separate efforts to put the full collection of Pseudo-Isidore into circulation. One assembly team, responsible for the A/B recension of the Pseudo-lsidorian forgeries, appears to have worked at Corbie. The location of their counterparts, responsible for the A 1 recension, is impossible to determine, though two key early manuscripts have been associated with diocesan centers.

The Influence of Incentive Structure on Group Performance in Assembly Lines and Teams

ABSTRACT: Modern manufacturing settings increasingly rely upon workgroups; however, evidence concerning the best fit among incentive structure, production environment, and group performance has been mixed. Young et al. (1993) examine the effect of group incentives on group performance in cooperative and noncooperative environments. Although theory and evidence from practice indicate that group incentives combined with cooperation should result in higher group performance, their results were contrary to this prediction. To further explore this issue, we examine the effect of individual, group, and mixed incentive structures on group performance in assembly lines and teams. We find no difference in group performance depending on incentive structure for assembly lines; however, group performance is higher under group incentives for teams. Supplemental analysis indicates group incentives support the teams’ ability to implement beneficial task strategies and although mixed incentives are theoretically appealing, they may send confusing signals to employees about where to direct their effort.

A team-oriented design methodology for mixed model assembly systems

Team-oriented approaches are widely being used in modern real life assembly systems, as are other modern systems. In this paper, first the literature of single and mixed model assembly line balancing, which plays an important role for the design of assembly systems, is reviewed. The associated literature matrixes reveal that team-oriented approaches do not have an intensive research area. Second, a team-oriented mathematical programming model for creating assembly teams (physical stations) in mixed model assembly lines is devised. Owing to the fact that this model is NP hard, a scheduling based heuristic algorithm is developed. The mixed model assembly line design methodology, which includes a team-oriented algorithm as a step, is proposed. Both model sequencing and worker transfer systems are included in the methodology. The algorithms for each step of the methodology are also coded by using MATLAB and MS Excel is used as the user interface. Furthermore, the presented methodology was applied in a chosen segment of a real life mixed model tractor assembly system.

Implementing Just‐in‐Time Assembly Methods in a Medium‐sized Scottish Electronics Company

There are both “Swedish” and “Japanese” models for the organization of final assembly. Discusses the theoretical and historical background to these models and the main practical differences between them. Provides an empirical study based on action research conducted in the final assembly area of a Scottish electronics company. The aims of the research were to effect change in the company by applying just‐in‐time (JIT) assembly methods, and to observe the process of change and the consequences for production of the cellular approach to assembly and the formation of assembly teams. Two projects were undertaken. In the first, a JIT cell was built for the assembly of a new product; this cell and an existing, conventional flowline operated in parallel for a period. In the second, a work team was formed, consisting of the operators assembling an older product on a machine‐paced line; the members of this team were given a significantly higher level of work autonomy than before. Provides a detailed account of the two projects.