General chemoenzymatic route to two-stereocenter triketides employing assembly line ketoreductases

The structural framework for the car’s assembly line simulation training system of the SWET(Simulated Work Environment Training) is designed overall, including two automatic car assembly lines and two manually run the disassembly line. The automatic control system of the car’s assembly line simulation training system is designed with the knowledge of electrical and electronic, SCM principles, counts the number of the car, automatically pause and open the line with alarm and automatic recovery control.

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Variation Analysis for Compliant Assembly

10.1115/imece2000-1787 ◽

2000 ◽

Author(s):

S. Jack Hu ◽

Yufeng Long ◽

Jaime Camelio

Keyword(s):

Sheet Metal ◽

Assembly Line ◽

Assembly Process ◽

Variation Analysis ◽

Assembly Lines ◽

Compliant Assembly ◽

Single Station ◽

Dimensional Variation ◽

Sheet Metal Assembly

Abstract Assembly processes for compliant non-rigid parts are widely used in manufacturing automobiles, furniture, and electronic appliances. One of the major issues in the sheet metal assembly process is to control the dimensional variation of assemblies throughout the assembly line. This paper provides an overview of the recent development in variation analysis for compliant assembly. First, the unique characteristics of compliant assemblies are discussed. Then, various approaches to variation modeling for compliant assemblies are presented for single station and multi-station assembly lines. Finally, examples are given to demonstrate the applications of compliant assembly variation models.

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Bucket Brigades to Increase Productivity in a Luxury Assembly Line

International Journal of Engineering Business Management ◽

10.5772/56837 ◽

2013 ◽

Vol 5 ◽

pp. 28 ◽

Cited By ~ 4

Author(s):

Filippo De Carlo ◽

Orlando Borgia ◽

Mario Tucci

Keyword(s):

Assembly Line ◽

Assembly Line Balancing ◽

Assembly Lines ◽

Manual Assembly ◽

Increase Productivity ◽

Assembly Line Balancing Problem ◽

High Level ◽

Simple Assembly ◽

A Company ◽

Bucket Brigades

One of the most challenging issues in manual assembly lines is to achieve the best balance of workloads. There are many analytic approaches to solve this problem, but they are often neglected, since they are time-consuming and require high level engineering skills. Fashion bags packaging lines must comply with a number of different products with low production volumes, while the organization of the line is often under the mere responsibility of the foreman, who balances workloads in an empirical way. The aim of this work is to evaluate the effectiveness of the arrangement of bucket brigades (BBs) for an assembly line of luxury handbags. To do this, it was decided to perform a testing activity in a company producing fashion handbags in order to compare the self-made design with the BBs and with a simple assembly line balancing problem algorithm. The originality of this research lies in the fact that there are no studies in the literature on BBs applied to the packaging of highly variable small batches. The results were excellent, showing the advantages of BBs in terms of flexibility, the reduction of work in the process and the ability to handle small anomalies.

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Study on Importance of Employee Performance Assesment and Lost Productive Time Rate Determination in Garment Assembly Lines

Fibres and Textiles in Eastern Europe ◽

10.5604/01.3001.0010.4638 ◽

2017 ◽

Vol 25 (0) ◽

pp. 119-126 ◽

Cited By ~ 2

Author(s):

Mahmut Kayar ◽

Öykü Ceren Bulur

Keyword(s):

Performance Assessment ◽

Assembly Line ◽

Employee Performance ◽

Assembly Line Balancing ◽

Line Balancing ◽

Assembly Lines ◽

Standard Time ◽

Productive Time ◽

Production Target

This study primarily includes theoretical information on the performance and lost productive time of a firm. Furthermore t-shirt sewing operations of a garment firm were analysed and time measurement for each operation was carried out by the time keeping method. By considering the measurements obtained, different performance estimations, the firm’s lost productive time rates, and the standard time was calculated within 5 different scenarios. According to each sewing standard time obtained, the assembly line balancing practice was carried out using the Hoffman method. Later on results of the assembly line balancing were compared, and the importance of employee performance assessment and its lost productive time rates for firms were discussed. The aim of the study was to emphasize the value of impeccable determination of the employee performance assessment and lost productive time rates. Consequently garment firms will be more cautious in calculating the standard time and will be able to reach their production target within the accurate measurement they obtain.

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Evaluation of System Reconfigurability Based on Usable Excess

Volume 2B: 40th Design Automation Conference ◽

10.1115/detc2014-34298 ◽

2014 ◽

Cited By ~ 1

Author(s):

Jeffrey D. Allen ◽

Jason D. Watson ◽

Christopher A. Mattson ◽

Scott M. Ferguson

Keyword(s):

Communication Systems ◽

Assembly Line ◽

Assembly Lines ◽

Automated Assembly ◽

Complex Engineered Systems ◽

Future Needs ◽

Key Factor ◽

Long Time ◽

Engineered Systems ◽

Over Time

The challenge of designing complex engineered systems with long service lives can be daunting. As customer needs change over time, such systems must evolve to meet these needs. This paper presents a method for evaluating the reconfigurability of systems to meet future needs. Specifically we show that excess capability is a key factor in evaluating the reconfigurability of a system to a particular need, and that the overall system reconfigurability is a function of the system’s reconfigurability to all future needs combined. There are many examples of complex engineered systems; for example, aircraft, ships, communication systems, spacecraft and automated assembly lines. These systems cost millions of dollars to design and millions to replicate. They often need to stay in service for a long time. However, this is often limited by an inability to adapt to meet future needs. Using an automated assembly line as an example, we show that system reconfigurability can be modeled as a function of usable excess capability.

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Increasing The Efficiency of The Cub Engine Assembly Lines In The Automotive Industry Using Ranked Positional Weight

MATEC Web of Conferences ◽

10.1051/matecconf/201821804028 ◽

2018 ◽

Vol 218 ◽

pp. 04028

Author(s):

Inaki Maulida Hakim ◽

Syarafi Auzan Mu’min ◽

Rolina Oktapiani Zaqiah

Keyword(s):

Production Process ◽

Automotive Industry ◽

Manufacturing Industry ◽

Assembly Line ◽

Consumer Demand ◽

Assembly Lines ◽

Production Flow ◽

Subsequent Increase ◽

The Right ◽

Positional Weight

In this modern era, the competition among the manufacturing industry, especially in the automotive sector will become increasingly tight which causes companies need to innovate so that satisfaction of the consumer can be maintained. The production process will be an important aspect in the automotive industry to maintain the quality of products and ensure consumer demand can be fulfilled. The problems that often occur in the production process is in the form of production flow constraints caused by workload unbalanced in the assembly lines. The imbalance causes the assembly lines do not run in a cycle time that is determined, so that consumer demand can not be meet in the right amount and companies need to spend more to mitigate them. Therefore, this study was conducted to balance workload on the assembly line by using line balancing form Ranked Positional Weight (RPW) with a subsequent increase in the efficiency and productivity of assembly line that affect production process runs without any contraints.

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Adjustment mode decision based on support vector data description and evidence theory for assembly lines

Industrial Management & Data Systems ◽

10.1108/imds-01-2017-0014 ◽

2018 ◽

Vol 118 (8) ◽

pp. 1711-1726 ◽

Cited By ~ 2

Author(s):

Youlong Lv ◽

Wei Qin ◽

Jungang Yang ◽

Jie Zhang

Keyword(s):

Assembly Line ◽

Historical Data ◽

Classification Model ◽

Support Vector ◽

Support Vector Data Description ◽

Vector Data ◽

Assembly Lines ◽

Content Type ◽

Input Layer ◽

Multi Classification

PurposeThree adjustment modes are alternatives for mixed-model assembly lines (MMALs) to improve their production plans according to constantly changing customer requirements. The purpose of this paper is to deal with the decision-making problem between these modes by proposing a novel multi-classification method. This method recommends appropriate adjustment modes for the assembly lines faced with different customer orders through machine learning from historical data.Design/methodology/approachThe decision-making method uses the classification model composed of an input layer, two intermediate layers and an output layer. The input layer describes the assembly line in a knowledge-intensive manner by presenting the impact degrees of production parameters on line performances. The first intermediate layer provides the support vector data description (SVDD) of each adjustment mode through historical data training. The second intermediate layer employs the Dempster–Shafer (D–S) theory to combine the posterior classification possibilities generated from different SVDDs. The output layer gives the adjustment mode with the maximum posterior possibility as the classification result according to Bayesian decision theory.FindingsThe proposed method achieves higher classification accuracies than the support vector machine methods and the traditional SVDD method in the numerical test consisting of data sets from the machine-learning repository and the case study of a diesel engine assembly line.Practical implicationsThis research recommends appropriate adjustment modes for MMALs in response to customer demand changes. According to the suggested adjustment mode, the managers can improve the line performance more effectively by using the well-designed optimization methods for a specific scope.Originality/valueThe adjustment mode decision belongs to the multi-classification problem featured with limited historical data. Although traditional SVDD methods can solve these problems by providing the posterior possibility of each classification result, they might have poor classification accuracies owing to the conflicts and uncertainties of these possibilities. This paper develops a novel classification model that integrates the SVDD method with the D–S theory. By handling the conflicts and uncertainties appropriately, this model achieves higher classification accuracies than traditional methods.

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Effective Cycle Time: A Real World Balancing Index for Paced Assembly Lines

Journal of Advanced Computational Intelligence and Intelligent Informatics ◽

10.20965/jaciii.2010.p0431 ◽

2010 ◽

Vol 14 (5) ◽

pp. 431-441

Author(s):

Konstantinos N. Genikomsakis ◽

◽

Vassilios D. Tourassis

Keyword(s):

Performance Measures ◽

Cycle Time ◽

Assembly Line ◽

Assembly Line Balancing ◽

Line Balancing ◽

Research Trend ◽

Time Variability ◽

Assembly Lines ◽

Simulation Experiments

Assembly Line Balancing (ALB) aims at optimally assigning the work elements required to assemble a product to an ordered sequence of workstations, while satisfying precedence constraints. Notwithstanding the advances and developments in ALB over the years, recent and thorough surveys on this field reveal that only a small percentage of companies employ ALB procedures to configure their assembly lines. This paradox may be attributed, to some extent, to the fact that ALB is addressed mostly under ideal conditions. Despite the time variability inherent in manufacturing tasks, there is a strong research trend towards designing and implementing algorithms that consider ALB on a deterministic basis and focus on the optimality of the proposed task assignments according to existing ALB performance measures. In this paper, the need to assess the performance of the proposed solutions of various algorithms in the literature is corroborated through simulation experiments on a benchmark ALB problem under more realistic conditions. A novel ALB index, namely the Effective Cycle Time, ECT, is proposed to assess the quality of alternative assembly line configurations in paced assembly lines operating under task times variations.

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