Work Measurement Method Research Articles

Research on the calibration method of winding deformation tester

Abstract The focus of this paper is the calibration method and process for winding deformation tester, encompassing its working principle, metrological characteristics, calibration conditions and measurement methods. The calibration conditions are divided into environmental conditions and measurement standards and other equipments. The measurement methods are divided into indication error of scanning frequency and indication error of amplitude ratio. The key steps in the calibration process are elaborated, including the selection of standard equipments, error analysis, data processing. The method’s feasibility is verified through experiments.

Workplace performance measurement: digitalization of work observation and analysis

AbstractProcess improvement initiatives require access to frequently updated and good quality data. This is an extremely difficult task in the area of production processes, where the lack of a process digital footprint is a very big challenge. To solve this problem, the authors of this article designed, implemented, and verified the results of a new work measurement method. The Workplace Performance Measurement (WPM) method is focused not only on the measurement of task duration and frequency, but also on searching for potential anomalies and their reasons. The WPM method collects a wide range of workspace parameters, including workers' activities, workers' physiological parameters, and tool usage. An application of Process Mining and Machine Learning solutions has allowed us to not only significantly increase the quality of analysis (compared to analog work sampling methods), but also to implement an automated controlling solution. The genuine value of the WPM is attested to by the achieved results, like increased efficiency of production processes, better visibility of process flow, or delivery of input data to MES solutions. MES systems require good quality, frequently updated information, and this is the role played by the WPM, which can provide this type of data for Master Data as well as for Production Orders. The presented authorial WPM method reduces the gap in available scholarship and practical solutions, enabling the collection of reliable data on the actual flow of business processes without their disruption, relevant for i.a. advanced systems using AI.

A novel digitalization approach for smart materials – ontology‐based access to data and models

Smart materials react to physical fields (e.g. electric, magnetic and thermal fields) and can be used as sensors, actuators and generators due to their bidirectional behavior. Easy and multiscale access to material data and models enables efficient research and development with regard to the selection of appropriate materials and their optimization towards specific applications. However, different working principles, measurement and analysis methods, as well as data storage approaches lead to heterogeneous and partly inconsistent datasets. The ontology‐based data access (OBDA) is a suitable method to access such heterogeneous datasets easily and quickly, while material models can transform material data across certain scales for different applications. In order to connect both capabilities, we present an extended approach enabling an ontology‐based data and model access (OBDMA), also supporting FAIR (Findable, Accessible, Interoperable, and Re‐usable). The OBDMA system comprises four main levels, the query, the ontology, the mapping and the database. Storing knowledge at these different levels increases the interchangeability and enables variable datasets, which is essential, especially for dynamic research fields such as smart materials. In our paper, the principles and advantages of the OBDMA approach are demonstrated for different subclasses of smart materials, but can be transferred to other materials, too.This article is protected by copyright. All rights reserved.

Analysis of Mental Workload on Counter Sales Using NASA-TLX Method

PT. XYZ is a service-oriented branch company that provides consumers with a wide range of products. Services provided by this company is divided into three main sections, namely sales, service, and spare part. One of the main parts is sales, which is selling units of cars carried out by counter sales to meet targets. The demand for achieving targets provides a psychological workload for counter sales. Therefore, it is necessary to measure the mental workload in this area. The work measurement method used in this research is NASA-TLX. This method was developed based on the emergence of subjective measurement needs in measuring workload using six indicators, namely mental demand, physical demand, temporal demand, own performance, effort, and level of frustration. The results showed that WWL values ​​were in the range of 88.33-91.67 and had a very high category. Several recommendations for improvement that need to be implemented include evaluating picket scheduling by considering predictions of increased customer visits, conducting routine training and providing motivation, and providing rewards as a form of appreciation for workers according to their achievements.

The reporting of work participation outcomes and measurement methods in randomized controlled trials: a systematic review

The reporting of work participation outcomes and measurement methods in randomized controlled trials: a systematic review

Evaluation on the Use of Plants and Equipment in Building Project Delivery in Imo State, Nigeria

Modern construction is characterized with complex designs, new and innovative materials that are sensitive with high precision. In addressing the accompanying challenges, mechanization of construction process is said to be the guarantee especially in this era of crash programmes and advancement in technology to reduce poor workmanship and eliminate avoidable holdup in construction processes in the industry. Amidst this belief, attributes of construction industry in Imo state still reflect ineffectiveness in the use of plant and equipment. Hence, the study assesses the involvement of plants and equipment in building delivery for improved project performance. Field survey and work measurement methods were adopted to gather both non-parametric and parametric data respectively. The survey design targeted the sampled building professionals while work measurement focused on selected earth and concrete works in the area of the study. Inferential and descriptive statistical tools of Chi-square on likert scale and Comparative measurements on work activities respectively were used to analyze the respective non-parametric and parametric data. Findings show that selection of various plants are dependent on their rates of use for increased site work productivity; while the socio-economic and political issues as militating factors against effective use of plants are determined by their levels of acceptance. It was also discovered comparatively that mechanization of construction processes is more time and cost effective in building project than manual approach at work. The study therefore recommends that a systematic and holistic awareness be created by the stakeholders on the usefulness of mechanization of construction process in physical development. Besides, government should enforce construction methodology plan as a mandatory document for approval of any building plans; while frantic effort should be targeted at reviving the abandoned steel manufacturing industry at Ajeokuta, Ogun state to revolutionize the construction methodology of construction industry in Nigeria.

Experimental investigation on cycle time in machining of forged crankshaft

Crankshaft is one of the most important component used in automobiles industries. Work study is an effective technique used to enhance the productivity of crankshaft manufacturing industry. It identifies the problems in terms of production time, number of processes and production rate. In present work, machining cycle time for forged crankshaft is investigated using work measurement method. It observed that machining time was more on two machining operations specifically in rough turning and grinding. Initial cycle time was 92.73 min for processing of crankshaft. After modifications, cycle time is reduced 88.63 min. It is found that machining cycle time is reduced by 4.1 min. This results in the improvement of cycle time by 4.42%. Further initial and final cost of machining is compared that is reduced 7%.

Identification of resonant vibrations of the miniature unmanned airplane with contact and non-contact measuring techniques

The paper describes application of two different vibration measurement methods for identification of natural modes of the miniature UAV. The aim of this research was to determine resonant frequencies and modes of mini-airplane within specified range of frequency values. Special measuring equipment was used including both contact and non-contact techniques. The measuring systems on equipment of the Institute of Aviation Technology in the Faculty of Mechatronics, Armament and Aerospace of Military University of Technology (Warsaw, PL) were used to conduct measurements. In traditional GVT methods a large number of sensors can be attached to the aircraft. The weight of sensors and cables is negligible in relation to the mass of the large aircraft. But for small and lightweight unmanned aerial vehicles, this could bring a significant mass component in relation to the total mass of the tested object. In this paper the methodology of GVT was presented. Two different measuring methods were applied, i.e. the contact method and the non-contact method. Using the dedicated apparatus in relation to mini-airplane, properly prepared in terms of mass distribution, rudders deflection stiffness and proper support, some resonant characteristics can be determined. The contact measuring system consists of a multi-channel analyzer, piezoelectric accelerometers, electrodynamic exciters, amplifiers, impedance heads and a computer with the Test. Lab Software. As the non-contact method a laser scanning vibrometer was used. The principle of its operation is based on the separation of the emitted laser beam. The returning beam reflected from a vibrating object is captured by the camera and compared to the reference beam. Dedicated software analyses collected data and on the basis of it creates animations of structural vibrational shapes and spectral plots within investigated frequency range. Object used for research is the mini-UAV Rybitwa – composite mini-plane with a classic aerodynamic layout manufactured in IAT MUT. In the work both measurement methods and some sample results were presented. Results referenced to dynamic properties of the mini-UAV can be applied in the future to FE model tuning.

ANALISIS JABATAN, BEBAN KERJA DAN PERHITUNGAN KEBUTUHAN PEGAWAI DI PUSAT DATA DAN STATISTIK PENDIDIKAN DAN KEBUDAYAAN

This study examines the gaps between job analysis, workload analysis and employee requirement calculations that had been formulated previously in Center for Education and Culture Statistics and their implementation. This qualitative descriptive study applied purposeful sampling by vetting nominations from staffs and their superiors. Evidence was collected through work measurement method using work sampling technique to set time standard in the area of on-desk data validation task only. Meanwhile, volume counts and timings for other stages of works were arrived at by interviews with the experienced employees involved in the processes. Based on the results, it was revealed that the total workload was not proportional to the amount of existing employees. Therefore, job analysis, workload analysis and employee requirement calculations which belong to the organization should be evaluated and improved so they can be utilized as guides in more accurate manpower planning. Furthermore, it is necessary to recruit and select new employees.

A Method to Monitor IGBT Module Bond Wire Failure Using On-State Voltage Separation Strategy

On-state voltage is an important thermal parameter for insulated gate bipolar transistor (IGBT) modules. It is employed widely to predict failure in IGBT module bond wires. However, due to restrictions in work environments and measurement methods, it is difficult to ensure the measurement accuracy for the on-state voltage under practical working conditions. To address this problem, an on-state voltage separation strategy is proposed for the IGBT modules with respect to the influence of collector current (Ic) and junction temperature (Tj). This method involves the separation of the on-state voltage into a dependent part and two independent parts during the IGBT module bond wire prediction. Based on the proposed separation strategy, the independent parts in the failure prediction can be removed, making it possible to directly monitor the voltage variations caused by bond wire failure. The experimental results demonstrate that the proposed diagnosis strategy can accurately predict the bond wire failure stage in an IGBT module under different conditions.

High performance computing for drug development on K computer

Massively parallel computations (MP-CAFEE) ware developed to calculate absolute binding free energies of small molecules bound to a protein by all-atom molecular dynamics. It uses the nonequilibrium work measurement and Bennett acceptance ratio methods to calculate the free energy difference between the bound and unbound states. The FUJI force field was developed in order to assign force field parameters to arbitrary organic molecules in a unified manner including proteins and nucleic acids. Its dihedral parameters agree with the torsion energy profiles calculated by high-level ab initio molecular orbital theory for the model systems of protein backbone. Comparing with various force fields it agrees well with recent observations by vibrational spectroscopy on Ramachandran angle's population of alanine dipeptide in water. MP-CAFEE with FUJI force field has an efficient parallel algorithm and enough accuracy for computer aided drug design.

Application of the Work Study to Balancing Hydraulic Component Assembly Lines

This paper applies the methods of Work Study to a certain hydraulic component company. We apply the work measurement method to measure the work time of various stations of assembly lines, and to find out both the bottle neck stations and the superfluous capability stations effecting on the line assembly capability. Basing on the principle of ECRS (Eliminate, Combine, Rearrange, Simple) and the line balancing theory, this paper provides the line balancing schema, including the improvement of the existing equipment, the reallocation of the work content for relative stations, the adjustment of the equipment and workers of some stations, the reduction of machine working time of some stations and the change of assembly line layout etc. After being improved, the work time of the bottle neck and other processes are controlled near the Taking Time. Comparing with the former assembly line, the production capability of assembly line improved up 45.6% and workshop condition is also improved.

An alternative work measurement method and its application to a manufacturing industry

Difficulties in determining the standard time justify the need to develop alternative methods to direct measurement procedures. The indirect methods which are comparison and prediction, standard data and formulation, predefined movement-time systems have several deficiencies in time measurement procedures. In this study, an alternative indirect work measurement method based on artificial neural networks (ANNs) is presented which is simple and inexpensive. For the application of the proposed method, the products that have similar production processes are selected among the whole product family produced in a manufacturing company. The standard times of the sampled products that are previously measured are used and the standard times of the remaining several products and semi-products are predicted by the proposed method. The model results show that the proposed method can be applied accurately in companies which produce similar products.

Efficiently development of the mechanics in turbo chargers by means of continuously working methods of measuring

Turbo chargers have established its place at diesel engines and are now capturing gasoline engines as well. Fatigue strength but first low oil consumption are important requirements for the use in modern automotive designs. Increased demands on mechanical development and on speed of response and on high loadings also keep the development departments busy. IAVF Antriebstechnik AG is developing and using continuously working measurement methods with high resolution for oil consumption and wear measurements. These methods e.g. can be performed simultaneously to save development time and to reduce the costs significantly.

A Comparison between CARS and ROMUM based on Human Interface Technology

This research compared CARS based on a computer system and ROMUM based on manual operation to measure the robot work. Time, accuracy, and usability of the analysis were selected as an evaluation index. In general, even though test results showed that the difference of the analysis time and the rate of error between computer work (CARS) and manual work (ROMUM) increased as the difficulty increased, there was not a certain linear relationship between these two works. This research discussed CARS developed as a computer supported system to measure the work time of a robot by attempting human-interface aspect to substitute the manual work measurement method based on PTS. The CARS was constructed as computer supported user oriented menu-driven type by taking advantage of ROMUM techniques. Therefore, compare to existing analytical method based on detailed basic motion, CARS could pursue the usability for user by selecting a module of unit motion according to the work content, minimize the analysis effort, and prevent errors as an effective work measurement system. Also, it might recognize unnecessary motion in advance and prevent execution of unnecessary motion by employing the analysis method according to the work content

Efficient work measurement system of manufacturing cells using speech recognition and digital image processing technology

Work measurement methods previously proposed require considerable time and effort by time study analysts because they have to measure the required time through direct observations. In this study, however, we propose a method which efficiently measures the standard times without involving human analysts by using speech recognition and digital image processing techniques. First, we implement a prototype system which can acquire the status of manufacturing cells through a speech recognition system. Second, using image processing, we suggest a method which consists of two main steps: motion representation and cycle segmentation. In the motion representation step, we first detect the motion of any object distinct from its background by differencing two consecutive images separated by a constant time interval. The images thus obtained then pass through an edge detector filter. Finally, the mean values of coordinates of significant pixels of the edge image are obtained. Through these processes, the motions of the observed worker are represented by two time series of data of worker location in horizontal and vertical axes. In the cycle segmentation step, we extract the frames which have maximum or minimum coordinates in one cycle, store them in a stack, and calculate each cycle time using these frames. In this step we also consider methods for detecting work delays due to unexpected events such as an operator’s movement out of the work area, or interruptions. To conclude, the experimental results show that the proposed method is very cost-effective and useful for measuring time standards for various work environments.

Meaningful Workplace Protection Factor Measurement: Experimental Protocols and Data Treatment

Workplace performance measurement of respiratory protective equipment (RPE) is fundamental to the understanding of how well wearers are protected. It forms the basis for guidance on which the selection of appropriate equipment is based. However, the measurement of this performance is open to many sources of interference and inaccuracy, reducing the value and relevance of the results, and is most difficult for devices providing the highest levels of protection. In this paper, a method for critically assessing collected workplace protection factor (WPF) data is validated. This method rejects unreliable data, using criteria based on the detection limits of the analytical measurement system. An iterative approach is also described which arrives at a supportable estimate of given non-parametric percentiles of the distribution of measured WPFs [such as the fifth percentile, conventionally taken to be the assigned protection factor (APF)]. Further pragmatic criteria, based on a combination of experimental experience and consideration from first principles, are suggested as the basis for any future studies of RPE performance. These will maximize the chances of valid measurements being made, and also provide insight into the level of confidence which can be placed on any of the results. A consequence of these criteria is that typical working environments and measurement methods are incapable of generating WPF data which can be considered reliable.

Internal noise in miniature electret microphones

Modern miniature electret microphones normally include an internal amplifier to buffer the very high electrical impedance of the electret motor. This amplifier, usually an FET source follower circuit, generates a part of the noise in the microphone output signal. The electrical noise originates in the semiconductor and in the resistive components of the electrical circuit. Recent developments have reduced the electrical noise considerably so that it is no longer the dominant source. The other noise sources are the resistive components of the mechanical and acoustical impedances within the microphone. This paper describes recent work and special measurement methods that have helped to identify and reduce the acoustical noise components.

Preliminary test method for the determination of surface firmness.

The Americans with Disabilities Act Accessibility Guidelines (ADAAG) specify that ground and floor surfaces should be firm, stable, and slip-resistant. These specifications are subjective; objective methods for assessing surface firmness and stability are lacking. Objective measures are needed to assess the accessibility of walking and wheeling surfaces and to improve accessibility for people with mobility limitations. This research study focused only on the development of an objective wheelchair work measurement method to assess surface firmness. Firmness was quantified in terms of the work per meter required to propel a wheelchair across the surface. Work was determined by using a SMARTwheel to measure the forces applied to the pushrim. This measurement method was evaluated on carpet, hard trail surfaces, and various playground surfacing materials. Measurements were also taken on an adjustable ramp set at different grades, cross slopes, and grade/cross slope combinations. Reliable results were obtained on all test surfaces except two (sand and pea gravel) which could not be negotiated by the test wheelchair rider according to the test protocol. The test method was capable of measuring a wide range of surface types, produced repeatable results on nearly all test surfaces, and was sensitive enough to measure 1% changes in grade and differences in surfacing materials. Comparisons between the measurements made on level surfaces and on various ramp angles demonstrated the feasibility of using the work per meter value for a specific ramp grade as pass/fail performance criteria for short distances of accessible surfaces. For outdoor recreational environments, this work measurement method would provide an objective measure of firmness which could be used to classify surfaces into categories (e.g., hard, firm, soft).

A work measurement method for application in Indian agriculture

The usual scales of rating in work measurement practices are based on subjective assessment of effort and walking speed of workers. In the present paper an attempt was made to correlate walking speed and stride length with selected anthropometric and physiological measurements (heart rates), using three groups of farm workers. Linear simple and multiple regressions were obtained to identify the best possible correlation between the above parameters. Accordingly, a rating scale was developed and applied in ploughing, transplanting, reaping and sheafing operation in rice cultivation. The result showed that the preferred speed of walking of the farm workers was 1.39 m/s and step frequency at that speed was 103 steps/min. On application of the suggested scale on the abovee four agricultural operations, it was observed that the majority of the workers' working loads and efforts were more than they should be.