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11 – 20 of over 100000
Article
Publication date: 1 April 2014

Janne Kiilunen and Laura Frisk

The purpose of this paper is to examine the long-term reliability of an anisotropic conductive adhesive (ACA) attached polyethylene terephthalate (PET) flex-on-board (FOB…

Abstract

Purpose

The purpose of this paper is to examine the long-term reliability of an anisotropic conductive adhesive (ACA) attached polyethylene terephthalate (PET) flex-on-board (FOB) assembly for industrial application used in harsh environments. In addition, the possibility of reducing reliability testing time was studied.

Design/methodology/approach

A−40/+125°C thermal cycling test with 5- and 14-minute soak times was used to study the reliability. To study the functionality of the FOB assembly during testing, a real-time resistance measurement was used together with a 90° peel strength test. Failure analysis was performed on samples using scanning electron microscopy and cross sectioning.

Findings

No failures or noticeable increase in the measured resistance values were seen during testing. The peel strength, however, decreased significantly with both soak times used. The highest drop in the mechanical strength occurred at the start of the temperature cycling tests. The time spent at the high temperature extreme seemed to have a greater impact on the peel strength than the number of temperature cycles. The failure mode of peel tested samples changed due to temperature cycling from interfacial delamination to cohesive failure. The temperature cycling was also observed to induce voiding inside the adhesive.

Originality/value

The paper illustrates the applicability of ACA attached PET flex in high reliability industrial applications. Additionally, testing methods for high reliability adhesive interconnections are discussed. Especially, the effect of temperature cycling soak time on peel test results and reliability testing time is studied.

Details

Soldering & Surface Mount Technology, vol. 26 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 1 December 1995

Michael M. Nkasu and Kwan Hung Leung

Describes a systematic procedure for the design of a manufacturingassembly system, which has been developed in response to the problemsassociated with the allocation of tasks to…

867

Abstract

Describes a systematic procedure for the design of a manufacturing assembly system, which has been developed in response to the problems associated with the allocation of tasks to workstations, under conditions of uncertainties (and, hence, risks) in some key system parameters. Adopts the methodology of stochastic modelling, whereby various probability distributions are integrated within a modified COMSOAL algorithm, as a means of addressing the uncertainties associated with key manufacturing assembly system variables, such as cycle time and task times. The proposed computer‐oriented methodology is code‐named CIMASD, and incorporates four basic objective criteria options: minimizing the number of workstations; minimizing the balance delay; minimizing the cycle time; or a combination of two or more. Discusses four variants of the CIMASD methodology, designed and equipped to reflect on various uncertainty circumstances under which manufacturing assembly system designs are performed in practice. Demonstrates the efficacy of the CIMASD methodology by applying two of its variants to a case study. Shows that the proposed methodology is capable of facilitating far more informative manufacturing system design than would otherwise be possible: CIMASD can incorporate effective cost saving features, which are useful in the planning, designing and scheduling of workstation tasks, in a typical manufacturing assembly system design.

Details

Integrated Manufacturing Systems, vol. 6 no. 6
Type: Research Article
ISSN: 0957-6061

Keywords

Article
Publication date: 26 August 2014

Pornthipa Ongkunaruk and Wimonrat Wongsatit

The purpose of this paper is to improve the productivity of a large-sized frozen chicken manufacturer in Thailand. It analyses the production process based on work study…

1154

Abstract

Purpose

The purpose of this paper is to improve the productivity of a large-sized frozen chicken manufacturer in Thailand. It analyses the production process based on work study principles and identifies the bottleneck operation. It develops three models for the chicken preparation process.

Design/methodology/approach

First, analyse the current production system by collecting the cycle time of all operations in the production process based on work study principles. Then, design the production network and identify the bottleneck operation. After that, three methods – based on line balancing (LB), theory of constraints, and JIT concepts or ECRS (eliminate, combine, rearrange and simplify) – are proposed and implemented in the actual production line.

Findings

With the ECRS concept, the authors implement combine by combining two stations into one station, such as handling and weighing, or weighing batter and mixing it with chicken. Then, Simplify is implemented at job E, or transporting chicken using a cart instead of walking. This method can improve the cycle time and reduce the number of employees. It can increase the line efficiency by up to 94.20 per cent, reduce the number of employees by 14 persons, and reduce the labour cost by 356,160 baht/year.

Originality/value

Most agro-industry manufacturing processes are labour intensive. Thus, production LB can help increase productivity and reduce costs. The authors found that the case study company designed the production line without aligning it with the production network. A simple improvement can be made by adjusting the sequence of the work. In addition, the current production line was not lean. Implementation of the ECRS concept to improve production can reduce the waiting time and simplify the job.

Details

Business Process Management Journal, vol. 20 no. 5
Type: Research Article
ISSN: 1463-7154

Keywords

Article
Publication date: 28 September 2010

Kürşad Ağpak

Cycle time fluctuations in assembly lines are one of the important reasons of re‐balancing. As a result of re‐balancing of assembly lines, it will be necessary to change task…

Abstract

Purpose

Cycle time fluctuations in assembly lines are one of the important reasons of re‐balancing. As a result of re‐balancing of assembly lines, it will be necessary to change task sequences or equipment locations. The purpose of this paper is to find the task sequence which enables assembly line balancing (ALB) with minimum number of stations (NS) for different cycle times such that tasks and equipment or fixture locations remain unchanged.

Design/methodology/approach

In this paper a heuristic which consist of two stages is proposed to find a common task sequence for different cycle times in assembly lines.

Findings

It is shown that optimal NS for different cycle times can be achieved with a fixed task sequence.

Research limitations/implications

The approach is limited to a single model case. Model variety together with cycle time variety can be investigated in further studies.

Practical implications

Assembly lines which require less time and cost for re‐balancing can be easily designed by the proposed approach.

Originality/value

ALB problem is handled with a new viewpoint. Also, it is observed that the proposed approach serves as a bridge between assembly line design and balancing. In this regard, it is thought to have an important place in the ALB literature.

Details

Assembly Automation, vol. 30 no. 4
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 7 March 2016

Sreedhar Karunakaran

The purpose of this paper is to eliminate the wastes and inefficient procedures in the maintenance organization of aircraft so as to reduce its downtime and increase mission…

1901

Abstract

Purpose

The purpose of this paper is to eliminate the wastes and inefficient procedures in the maintenance organization of aircraft so as to reduce its downtime and increase mission availability.

Design/methodology/approach

Customized lean Six Sigma (LSS) was applied at the task level and servicing cycle level to reduce the task content, cycle length and resources in servicing. The loading of the servicing facility was simulated through a simulation program developed from a statistical analysis of historical data for validating/simulating/determining optimum loading of servicing facility with refined tasks, reduced cycle length and resources. In simulation, the optimum combination of manpower, resources and infrastructure at the facility level was determined through sensitive analysis and design of experiments (DoE).

Findings

Optimization at the task level and its re-organization at the servicing cycle level reduced the cycle length by 55-68 per cent and manpower resources by 26 per cent. This further reduced facility-level manpower by 25 to 40 per cent, capacity requirements by more than 33 per cent and annual aircraft downtime by 78 per cent. The approach reduced the average number of aircraft undergoing servicing at each airbase at any time from 2.35 to just 0.76 and increased the mission availability to 20 per cent.

Originality/value

The hallmark of the paper has been the design of LSS approach from structured historical data and its validation through innovative simulation. The multi-pronged bottom-up approach practically bundles all wastes resident in the maintenance organization. The paper provides cursory approach to lean practitioners in the elimination of wastes in the maintenance of capital assets like aircraft.

Details

International Journal of Lean Six Sigma, vol. 7 no. 1
Type: Research Article
ISSN: 2040-4166

Keywords

Article
Publication date: 1 June 1992

Festus O. Olorunniwo

Maintenance‐related costs contribute significantly to equipment life‐cycle costs. In practice, maintenance works are not perfect in the sense that they cannot restore the…

Abstract

Maintenance‐related costs contribute significantly to equipment life‐cycle costs. In practice, maintenance works are not perfect in the sense that they cannot restore the equipment to a “good‐as‐new” condition. Utilizing the concept of improvement factors to model the imperfect characteristics of most maintenance works, proposes a model which determines the number and timing of preventive maintenance works which are required before the equipment is overhauled. It also determines how many overhauls will be economically required before a decision is made to dispose of the equipment. The equipment disposal decision is based on an analysis of replacements which are constraints to be at the end of time cycles which may have unequal numbers of time‐periods and where the time‐periods do not have to be of equal length. This proposed replacement analysis is an extension of a well‐known replacement model in the literature.

Details

International Journal of Quality & Reliability Management, vol. 9 no. 6
Type: Research Article
ISSN: 0265-671X

Keywords

Abstract

Details

The Economics of Time Use
Type: Book
ISBN: 978-1-84950-838-4

Article
Publication date: 9 May 2023

Ercan Akan

The aim of this study is to provide a holistic analysis of all possible maritime business logistics processes related to import and export shipments in a fuzzy environment through…

Abstract

Purpose

The aim of this study is to provide a holistic analysis of all possible maritime business logistics processes related to import and export shipments in a fuzzy environment through a case study of a maritime logistics company based on the as-is and to-be models within business process management (BPM).

Design/methodology/approach

The analyses considered the following perspectives: (i) in the stage of the process identification, the definition of the problem was carried out; (ii) in the stage of the process discovery, ocean department was divided into ocean export/import operation departments; ocean export/import operation were divided into freight collect/prepaid operation processes; ocean export/import logistics activity groups were broken down into sub-activities for freight collect/prepaid operation; the logistics activity groups and their sub-activities were defined; each sub-activity as either operation or documentation process group was classified; the durations of sub-activities were evaluated by decision-makers (DMs) as fuzzy sets (FSs); the monthly total jobs activities were estimated by DMs as FSs; the applied to monthly jobs activities of total shipments were estimated by DMs as FSs; the durations of each sub-activities were aggregated; the duration of the logistics activity groups and the sub-activities for per job were calculated; the cumulative workload of logistics activity groups and sub-activities were calculated; the duration of sub-activities for per job as operation or documentation departments were calculated, (iii) in the stage of the process analysis, cumulative ocean export/import workload as operation or documentation for freight collect/prepaid were calculated; duration of activity groups and sub-activities for per job as operation or documentation were calculated; cumulative workload activity groups and sub-activities as operation or documentation were calculated, (iv) in the stage of the process redesign, cumulative workload, process cycle time as operation and documentation group and required labor force were calculated; the process cycle time of the theoretical, the as-is model and the to-be model were calculated: (i) the theoretical minimum process cycle time without resource were calculated by the critical path method (CPM), (ii) the process cycle time of the as-is model perspective with the 1 person resource constraint and (iii) the process cycle time of the to-be model perspective with the 2-person resource constraint were calculated by the resource constrained project scheduling problem (RCPSP) method.

Findings

The methodology for analyzing the ocean department operation process was successfully implemented in a real-life case study. It is observed that the results of the to-be model can be applicable for the company. The BPM-proposed methodology is applicable for the maritime logistics industry in the present study; however, it can be applied to other companies in maritime logistics as well as other industries.

Originality/value

This study contributes to research using BPM methodology in maritime logistics. This is the first study the logistics process analyses were carried out in terms of including all operation processes for a company. All processes were analyzed by using BPM methodology in maritime logistics. This study demonstrated the application of the BPM as-is and to-be models to maritime logistics. The as-is and the to-be models of the BPM methodology were applied in maritime logistics.

Research implications

This methodology applied in this study can enable organizations operating in the time-urgent maritime logistics sector to manage their logistics processes more efficiently, increase customer satisfaction, reduce the risks of customer loss due to poor operational performance and increase profits in the long term. Through the use of these methodologies utilizing FSs, the CPM and the RCPSP methods, this study is expected to make contributions to the BPM literature and provide original insights into the field. Furthermore, this study will undertake a comprehensive analysis of maritime logistics with respect to BPM to deliver noteworthy contributions to the maritime logistics literature and provide original perspectives into the field.

Article
Publication date: 4 April 2023

Deedar Hussain and Manuel Carlos Figueiredo

The evaluation of time-based performance is a valued approach in the lean management thinking which is based on delivering value from customer's perspective. This approach…

946

Abstract

Purpose

The evaluation of time-based performance is a valued approach in the lean management thinking which is based on delivering value from customer's perspective. This approach contributes for long-term competitiveness and success in today's business environment. The focus of this study is to analyse the cycle time and manufacturing lead time with value stream mapping (VSM) in the preparatory stage of the textile fabric manufacturing process and to identify and improve the non-value adding activities in the value chain (VC). The study presents an insight on the translation of performance improvement across functions and how upstream supply chain (SC) segments can be linked in the performance improvement program. It also covers how the application of VSM improves visibility and planning flexibility in textile fabric manufacturing process.

Design/methodology/approach

The time-based performance was evaluated using VSM and recording of the activity times in the existing process. The impact of the quality of supplier's raw material was also measured contributing to identify the strategy for procurement and the means to establish a feedback system to the upstream segments of the SC. The methodology of VSM, observation of the practice and the expertise of the individuals involved with the process were utilised to develop the value stream maps and to identify value adding activities, non-value adding activities, existing gaps and plans for improvement.

Findings

The means for improving the time-based performance were identified and their impact was measured. The factors responsible for improvement are related to the production system and with the procurement strategy. The improvement was achieved in terms of available capacity utilisation, balancing the work flow in the preparatory stages, visibility of the process by measuring its capability and flexibility for the planning function. The study revealed that the effectiveness and enhancement of VSM and related tools should be adopted to address the issue of limiting success rates of long term and repeating application of such tools. Continuous improvement, innovations and the systematic embedding of VSM in the process life cycle provide the ways for achieving long-term success.

Research limitations/implications

The paper presents a real and in-depth study on the application of VSM in the textile manufacturing process. The scope of the study is broad; it covers activities across functions with actual estimates of activity times in the manufacturing process for the focused value streams. It offers researchers the opportunity to analyse the translation of productivity improvement across functions and how upstream SC segments can be linked in a performance improvement program.

Practical implications

The study offers useful insight for the managers in textile manufacturing and other sectors for improving the time-based performance and achieving higher utilisation of capacity. It identified the production factors and their impact on warping and sizing cycle time in selected value streams and those which share common activities. It also identified the directions for future research when repeating the application of VSM in the continuous improvement cycle. Furthermore, since the industries need to progress towards advanced systems including Industry 4.0 standards, adoption of advanced VSM tool with relevant technology can align their production systems to develop the required capability. This will also bring a sustainable competitive advantage in the system.

Social implications

The focused sector is stagnant in terms of productivity and innovation. The adoption of the advanced tools can facilitate the implementation of continuous improvement and innovation strategies.

Originality/value

The main focus of this study is to analyse and improve the cycle time in the preparatory stage of the fabric manufacturing process. This has impact on other important and tangible measures including capacity utilisation and work flow and intangible measures including production planning flexibility and process visibility. The improvement impact is across departments.

Details

Business Process Management Journal, vol. 29 no. 3
Type: Research Article
ISSN: 1463-7154

Keywords

Article
Publication date: 1 July 1991

Scott R. Swenseth and Frank P. Buffa

This article provides a discussion of key components for thedecisionmaker concerned with the logistical issues of implementing aJust‐in‐Time (JIT) manufacturing philosophy. A JIT…

Abstract

This article provides a discussion of key components for the decisionmaker concerned with the logistical issues of implementing a Just‐in‐Time (JIT) manufacturing philosophy. A JIT philosophy promotes reduced cycle times that provide benefits not normally considered in traditional inventory models and presents new concerns for the purchasing and logistics functions. The ramifications are investigated of a JIT implementation using an inventory‐theoretic modelling procedure modified and expanded to incorporate these considerations. The resulting cost comparisons indicate that the lead time variability associated with uncertain transit times in JIT is critical in the determination of order cycle time, order point, safety stock and the holding cost of the safety stock.

Details

International Journal of Operations & Production Management, vol. 11 no. 7
Type: Research Article
ISSN: 0144-3577

Keywords

11 – 20 of over 100000