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THE improvement in the British standard of living is generally desired. Politicians have not only subscribed to that ideal but some of them have indicated the rate at which we…
Abstract
THE improvement in the British standard of living is generally desired. Politicians have not only subscribed to that ideal but some of them have indicated the rate at which we should advance. There are, however, certain trends in the country's economic life which must be reversed if we are to make any progress in that direction.
Ke Yi Zhou and Shaolin Hu
The similarity measurement of time series is an important research in time series detection, which is a basic work of time series clustering, anomaly discovery, prediction and…
Abstract
Purpose
The similarity measurement of time series is an important research in time series detection, which is a basic work of time series clustering, anomaly discovery, prediction and many other data mining problems. The purpose of this paper is to design a new similarity measurement algorithm to improve the performance of the original similarity measurement algorithm. The subsequence morphological information is taken into account by the proposed algorithm, and time series is represented by a pattern, so the similarity measurement algorithm is more accurate.
Design/methodology/approach
Following some previous researches on similarity measurement, an improved method is presented. This new method combines morphological representation and dynamic time warping (DTW) technique to measure the similarities of time series. After the segmentation of time series data into segments, three parameter values of median, point number and slope are introduced into the improved distance measurement formula. The effectiveness of the morphological weighted DTW algorithm (MW-DTW) is demonstrated by the example of momentum wheel data of an aircraft attitude control system.
Findings
The improved method is insensitive to the distortion and expansion of time axis and can be used to detect the morphological changes of time series data. Simulation results confirm that this method proposed in this paper has a high accuracy of similarity measurement.
Practical implications
This improved method has been used to solve the problem of similarity measurement in time series, which is widely emerged in different fields of science and engineering, such as the field of control, measurement, monitoring, process signal processing and economic analysis.
Originality/value
In the similarity measurement of time series, the distance between sequences is often used as the only detection index. The results of similarity measurement should not be affected by the longitudinal or transverse stretching and translation changes of the sequence, so it is necessary to incorporate the morphological changes of the sequence into similarity measurement. The MW-DTW is more suitable for the actual situation. At the same time, the MW-DTW algorithm reduces the computational complexity by transforming the computational object to subsequences.
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Gualtiero Fantoni, Salam Qaddoori Al-Zubaidi, Elena Coli and Daniele Mazzei
This work reports on a developing method time measurement system for measuring manufacturing and assembly processes automatically. This automatic system enables the production…
Abstract
Purpose
This work reports on a developing method time measurement system for measuring manufacturing and assembly processes automatically. This automatic system enables the production engineers and management to detect, process, and display concise and accurate information about the operations in real time.
Design/methodology/approach
This system is based on Internet of things technology and RFID-antenna. This methodology consists of seven main steps and one final optimization step. Mainly, the operator is equipped by RFID reader, and the work station tools and devices are provided by RFID tags. Responding the RFID tags to the reader will refer to the certain operations, the difference time between start and end of the operations will be collected immediately and calculated by the microprocessor of the system.
Findings
This automatic system is promising, considering the accurate time measurements and recommendations that obtained from the case study which includes measuring manual assembly operations to be followed in order to overcome the limitations which are not only technical but also managerial, legal and organizational.
Research limitations/implications
The acquired data about timing and duration of individual operations are anonymized to guarantee the compliance with respect to the privacy laws (GDPR and Italian work's laws).
Originality/value
This work presents a unique system to measure the time instead of traditional methods in the factories environment and satisfies the requirements to study the recommendations in order to overcome the challenges.
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Avital Bechar and Moshe Eben-Chaime
Labor is the largest single cost contributor in agriculture. Accurate estimation of labor requirements is, thus, a key to cost reduction. Work measurement is the professional…
Abstract
Purpose
Labor is the largest single cost contributor in agriculture. Accurate estimation of labor requirements is, thus, a key to cost reduction. Work measurement is the professional discipline for this type of estimations, in the industrial engineering domain. Horticulture, however, lays a substantial barrier to work and, thus, to work measurement. Till harvesting, its products – fruits/flowers, are in fixed positions, and for all tasks the workers have to arrive at the plant. The purpose of this paper is to develop, test and analyze a system to perform horticultural work study in agricultural environments in order to accurately estimate the required amount of labor for each activity and to improve productivity.
Design/methodology/approach
In this paper, the development of an advanced system for work study on a hand-held computer (HHC) platform for horticultural work measurement is presented and an experimental study was conducted. The methodology consists of characteristics of the system platform including hardware, interface and software, development of a dedicated measuring software, a controlled experiment in agricultural environment and a statistical analysis.
Findings
The study shows that a single surveyor who uses traditional tools is subject to measurement errors, which can be reduced only with the assistance of a second surveyor. The study further shows that the HHC platform enables to avoid this second surveyor – a single surveyor who uses the HHC platform performs as accurate as two surveyors who use traditional tools. Of course, being computers, the HHC platform maintains the advantage of error free data transfer, in practically negligible time.
Originality/value
This paper presents a unique approach to perform work study in agricultural environment and contributes to minimize the errors accumulated in the process and the manpower required to perform the measurements.
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Azharul Karim and Kazi Arif‐Uz‐Zaman
The purpose of this paper is to develop an effective methodology for implementing lean manufacturing strategies and a leanness evaluation metric using continuous performance…
Abstract
Purpose
The purpose of this paper is to develop an effective methodology for implementing lean manufacturing strategies and a leanness evaluation metric using continuous performance measurement (CPM).
Design/methodology/approach
Based on five lean principles, a systematic lean implementation methodology for manufacturing organizations has been proposed. A simplified leanness evaluation metric consisting of both efficiency and effectiveness attributes of manufacturing performance has been developed for continuous evaluation of lean implementation. A case study to validate the proposed methodology has been conducted and proposed CPM metric has been used to assess the manufacturing leanness.
Findings
Proposed methodology is able to systematically identify manufacturing wastes, select appropriate lean tools, identify relevant performance indicators, achieve significant performance improvement and establish lean culture in the organization. Continuous performance measurement matrices in terms of efficiency and effectiveness are proved to be appropriate methods for continuous evaluation of lean performance.
Research limitations/implications
Effectiveness of the method developed has been demonstrated by applying it in a real life assembly process. However, more tests/applications will be necessary to generalize the findings.
Practical implications
Results show that applying the methods developed, managers can successfully identify and remove manufacturing wastes from their production processes. By improving process efficiency, they can optimize their resource allocations. Manufacturers now have a validated step by step methodology for successfully implementing lean strategies.
Originality/value
According to the authors' best knowledge, this is the first known study that proposed a systematic lean implementation methodology based on lean principles and continuous improvement techniques. Evaluation of performance improvement by lean strategies is a critical issue. This study develops a simplified leanness evaluation metric considering both efficiency and effectiveness attributes and integrates it with the lean implementation methodology.
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Fernanda Assef, Cassius Tadeu Scarpin and Maria Teresinha Steiner
The purpose of this paper is to present a precise comparison between a pre-determined time rules and the evaluation performed with the help of a manual chronometer using data from…
Abstract
Purpose
The purpose of this paper is to present a precise comparison between a pre-determined time rules and the evaluation performed with the help of a manual chronometer using data from a line assembly in an automotive industry besieged in the state of Paraná, Brazil. Nowadays, it is possible to verify several tools of measurement of task times, some taking less time and causing less wear of the evaluator than others, but not being in accordance with the real conditions of the workers of a certain industry.
Design/methodology/approach
The developed paper has its methodology based on two methods of time analysis, one of them being an adaptation of the MODular Arrangement of Predeterminated Time Standard (MODAPTS) method – called MODAPTS 2. This method is used by the industry in analyzed in this work and the other through the use of simple manual timing, through the digital timer, of the stages developed in a workstation.
Findings
The study shows that for each operation analyzed, thus presenting a situation of minimum waste, it becomes possible to judge which reasons exist for the operator during manual timekeeping not to reach the optimum times generated by the system of pre-determined times and movements (PMTSs) questioned.
Research limitations/implications
This study is conducted on an automotive enterprise in a period of confidentiality, which means that only a single workstation is able to be studied. This means that the comparison obtained between the time measurements methods used, and the evaluation of the MODAPTS is carried out with the best possible movements and gestures, disregarding then that the wastes can still be postulated to the whole assembly line.
Originality/value
With the automation in industry, where assemble tasks are usually developed manually, it is believed possible to discard the option of measuring task times in its classic and manual form, using a timer, yet during this process, there will be variables that may not be considered by pre-determined measurements methodologies. The work developed by this paper presents different variables that are not examined by the methods of PMTS, not frequently seen in the literature, as well as the difference that occurs between the measurement of times with stopwatch and the use of PMTS, which, in its original form, disregards the wastes that the operator has in their movements.
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METHOD STUDY, as the name implies, is that part of Work Study which makes a careful and critical examination of the methods currently employed either in factory or office. It is…
Abstract
METHOD STUDY, as the name implies, is that part of Work Study which makes a careful and critical examination of the methods currently employed either in factory or office. It is not concerned with standards of performance or schemes for payment by result. Instead, it aims at cutting out movements or efforts which are not necessary and, in general, improving the methods in use. It uses charts and diagrams; cameras to record still or moving pictures; models and measuring instruments. Uninterrupted attention is concentrated on the study in hand for whatever time it requires.
ONE effect of sharing a common language with America is the imposition of a surfeit of books on matters like work study, in which our own literature is modest indeed. The almost…
Abstract
ONE effect of sharing a common language with America is the imposition of a surfeit of books on matters like work study, in which our own literature is modest indeed. The almost simultaneous publication of two books with a common subject is therefore very unusual. They both deal with work measurement, one in forty‐seven chapters and the other in fifteen. Since books are not judged by a quantitative standard this is no guide to their respective merits.
THROUGHOUT the world today, there are millions of people living in misery and disease, and on the verge of starvation. The dominating feature of the next decade will be the…
Abstract
THROUGHOUT the world today, there are millions of people living in misery and disease, and on the verge of starvation. The dominating feature of the next decade will be the assertion of all peoples in the newly‐developing countries of their claim to a greater share of the world's goods. There will be a revolution in people's expectations: they will wish to achieve the break‐through from their present stage of poverty during the span of this present generation. Most prominent statesmen in the richer countries recognise that this is the central problem facing mankind. The need now is for their wider public also to understand this and for the governments of these countries to take collective and timely action. Modern management in the broadest sense should take account of these new and very striking forces.
FOURTEEN years ago 16% of all employees in our manufacturing industries were what are commonly described as ‘white collar’ workers. They belonged to the group that includes…
Abstract
FOURTEEN years ago 16% of all employees in our manufacturing industries were what are commonly described as ‘white collar’ workers. They belonged to the group that includes clerical, technical and administrative staffs. If that seems a very high proportion what can be thought of the fact that by 1960 the figure had risen to 21%? The actual rate of growth is even more startling. During that 12 years the total number of employees in manufacturing industry increased by 12% but in the same period the ‘white collar’ workers in that section of the economy rose by 48%, according to figures issued by the Ministry of Labour.