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Focuses on schemes to reduce inventory miscounts from the operational management point of view. An internal audit procedure is devised for identifying most of the data‐entry errors, which are one of the main causes of inventory miscounts during the flow of material through in‐transit stations. Inventory miscount errors, which escape the internal audit procedure, are further reduced through cycle counting. Divides stations with a material‐flow network into two categories – external and internal stations. Further subdivides internal stations into in‐transit and stock stations. Identifies and corrects most of the data‐entry errors by monitoring the compliance of certain rules individually at each in‐transit station and collectively at all in‐transit stations. Optimally determines the frequencies for cycle counting by minimizing the sum of the cycle‐counting cost and the penalty cost owing to additional stockouts and over‐stocking on account of inventory miscounts. The suggested internal procedure and cycle counting with revised frequencies were implemented in a company dealing with spare‐parts distribution; realizing an annual saving of about $1 million just a year after the implementation of the programme.

Engineering components/structures with geometric discontinuities normally bear complex and variable loads, which lead to a multiaxial and random/variable amplitude stress/strain state. Hence, this study aims how to effectively evaluate the multiaxial random/variable amplitude fatigue life.

Recent studies on critical plane method under multiaxial random/variable amplitude loading are reviewed, and the computational framework is clearly presented in this paper.

Some basic concepts and latest achievements in multiaxial random/variable amplitude fatigue analysis are introduced. This review summarizes the research status of four main aspects of multiaxial fatigue under random/variable amplitude loadings, namely multiaxial fatigue criterion, method for critical plane determination, cycle counting method and damage accumulation criterion. Particularly, the latest achievements of multiaxial random/variable amplitude fatigue using critical plane methods are classified and highlighted.

This review attempts to provide references for further research on multiaxial random/variable amplitude fatigue and to promote the development of multiaxial fatigue from experimental research to practical engineering application.

In order to improve the computation efficiency of the four-point rainflow algorithm, a one-stage extraction four-point rainflow algorithm is proposed based on a novel data preprocessing method.

In this new algorithm, the procedure of cycle counting is simplified by introducing the data preprocessing method. The high efficiency of new algorithm makes it a preferable candidate in fatigue life online estimation of structural health monitoring systems.

According to the data preprocessing method, in the process of cycle extraction, all equivalent cycles can be extracted at just one stage instead of two stages in the four-point rainflow algorithm, where the cycle extraction has to be performed from the doubled residue. Besides, there are no residues in the new algorithm. The extensive numerical simulation results demonstrate that the accuracy of new algorithm is the same as that of the four-point rainflow algorithm. Moreover, a comparative study based on a long input data sequence shows that the computation efficiency of the new algorithm is 42% higher than that of the four-point rainflow algorithm.

This merit of new algorithm makes it preferable in some application scenarios where fatigue life estimation needs to be accomplished online based on massive measured data. And it may attribute to preprocessing of input data sequence before data processing, which provides beneficial guidance to improve the efficiency of existing algorithms.

The purpose of this scientific work is to simulate the fatigue damage under random loading taking into account the mean stress effect on fatigue lifetime and using the rainflow counting technique to assess the fatigue damage.

The study of fatigue under random loading is based on same concepts which as constant loading with addition of damage summation. The damage of materials due a stress cycle depends not only on the alternating stress but also on the mean stress.

The cycles counting simulation method allows quantifying the hysteresis loops, even if for small amplitude stresses.

The cycles are low or medium; the damage occurs most often, the higher values of alternating stresses cause the most failure of materials.

The purpose of this scientific work is to simulate the fatigue damage under random loading, taking into account the mean stress effect on fatigue lifetime and using the Rainflow counting technique to assess the fatigue damage by the Ansys software. The used material is aluminum alloy 6082-T6. A comparison with literature results has confirmed this investigation in this paper.

The study of fatigue under random loading is based on the same concepts as constant loading with the addition of damage summation. The proportion of damage caused by a stress cycle depends not only on the alternating stress but also on the mean stress.

Analysis of the fatigue damage shows that the number of relative damage due to each cycle.

This paper aims to simulate the fatigue damage under random loading for aluminum alloys.

Engineering components/structures are usually subjected to complex and variable loads, which result in random multiaxial stress/strain states. However, fatigue analysis methods under constant loads cannot be directly applied to fatigue life prediction analysis under random loads. Therefore, the purpose of this study is how to effectively evaluate fatigue life under multiaxial random loading.

First, the average phase difference is characterized as the ratio of the number of shear strain cycles to the number of normal strain cycles, and the new non-proportional additional hardening factor is proposed. Then, the determined random typical load spectrum is processed into a simple variable amplitude load spectrum, and the damage in each plane is calculated according to the multiaxial fatigue life prediction model and Miner theory. Meanwhile, the cumulative damage can be calculated separately by projection method. Finally, the maximum projected cumulative damage plane is defined as the critical plane of multiaxial random fatigue.

The fatigue life prediction capability of the method is verified based on test data of TC4 titanium alloy under random multiaxial loading. Most of the predicting results are within double scatter bands.

The objective of this study is to provide a reference for the determination of critical plane and non-proportional additional hardening factor under multiaxial random loading, and to promote the development of multiaxial fatigue from experimental studies to practical engineering applications.

Examination of steel moment resisting frames after the 1994 Northridge earthquake showed fatigue cracks presented in the beam–column connections of the frames. These observations indicate that fatigue failure may occur in the steel components of building structures in an earthquake event. To apply the fatigue design approach using the Palmgren–Miner’s rule for steel components of the moment resisting frames requires the knowledge regarding the damage index value at fatigue failure. The purpose of this paper is to perform fatigue tests to give the first damage values of steel components subjected to real earthquake-induced loadings.

The added-damping-and-stiffness steel plates which are used in building structures for earthquake mitigation were fabricated and tested by constant amplitude, SAC block and earthquake-induced loadings to failure. The earthquake loadings were obtained from the dynamic analysis of a steel frame with the mentioned plates. The load cycles of the SAC block and the calculated earthquake loadings were counted using the rainflow-counting method, and the damage index value of each specimen were calculated using the Palmgren–Miner’s rule.

Reverse stiffness obtained from cyclic load-displacement loops is a robust and consistent parameter that can be used for determining fatigue failure of tested components. The Palmgren–Miner’s damage values at failure, caused by earthquake loadings, are smaller than 1, and in addition, are also smaller than those obtained from the tests of the SAC block loading. The large-amplitude cycles in the earthquake loading produce large damage on the specimens, and intermediate range cycles also produce damage that should not be neglected in the fatigue analysis.

Today’s building design code allows large plastic deformation to occur in steel frames during an earthquake. However, the pre-Northridge earthquake steel frames showed fatigue cracks without the expected substantial plastic deformation at beam flanges. Proposed solutions to this problem were the reduced beam section neglecting the existence of the cracks at beam–column connections. This study considered the fatigue phenomenon in steel frames and provided the first set of tested fatigue damage values for steel components subjected to realistic earthquake loadings, which offered a possible method of dealing with fatigue cracks in the steel components of a building structure.

For a manufacturing company, inventory control and management is crucial to ensure smooth production and sustainable sales performance, as well as preventing stockout that will result in customer switch to competitors. This paper aims to examine the effectiveness of cycle count activities, one of the inventory control tools to manage inventory. Beside, this study also wishes to identify any loopholes in practices and procedures in inventory control of companies.

One of the lubricant manufacturing companies in Malaysia was selected as a case study and mixed method data collection of document analysis and observation were used. The analysis and examination was conducted by using Committee of Sponsoring Organization of the Treadway Commission Framework 2013 as guidance.

This study found that problems in inventory control can be caused by inconsistency of practices due to incomplete or absent standard operating procedures. Furthermore, no segregation of duties and excessive reliance on one person to conduct many tasks will lead to human error and fraud.

This paper enhances the theoretical understanding on the inventory control and management system applied in the manufacturing organization particularly. However, frequent changes of the management in the organization of the case study make the study difficult to obtain consistent information. Not all standard operating procedures were revised or updated and available for examination. In addition, some of the reports needed for investigation are confidential and requests to observe and scrutinize information from those documents are denied by the company. Thus, more in-depth analysis and verification on the issues of interest were unable to be conducted.

This study provides an indicator that cycle count activities need to be conducted frequently on a regular basis so that the physical inventory and recording system are accurate. Cycle count activities also must involves various related departments in the company in which regular training is essential to ensure employees are aware and understand their responsibility and accountability on the inventory.

This study is original as it focuses on the inventory control management of one of the largest lubricant manufacturing in Malaysia, particularly on cycle count activities which is scare in literature. Furthermore, the company allows research access to the documents and operations conducted in the company, which is usually difficult to obtain from many companies.

The purpose of this study is to review the existing fatigue and vibration-based structural health monitoring techniques and highlight the advantages of combining both approaches.

Fatigue monitoring requires a fatigue model of the material, the stresses at specific points of the structure, a cycle counting technique and a fatigue damage criterion. Firstly, this paper reviews existing structural health monitoring (SHM) techniques, addresses their principal classifications and presents the main characteristics of each technique, with a particular emphasis on modal-based methodologies. Automated modal analysis, damage detection and localisation techniques are also reviewed. Fatigue monitoring is an SHM technique which evaluate the structural fatigue damage in real time. Stress estimation techniques and damage accumulation models based on the S-N field and the Miner rule are also reviewed in this paper.

A vast amount of research has been carried out in the field of SHM. The literature about fatigue calculation, fatigue testing, fatigue modelling and remaining fatigue life is also extensive. However, the number of publications related to monitor the fatigue process is scarce. A methodology to perform real-time structural fatigue monitoring, in both time and frequency domains, is presented.

Fatigue monitoring can be combined (applied simultaneously) with other vibration-based SHM techniques, which might significantly increase the reliability of the monitoring techniques.

The purpose of this paper is to investigate the fatigue crack growth (FCG) under random loading using analytical methods.

For this purpose, two methods of cycle-by-cycle technique and central limit theorem (CLT) were used. The Walker equation was used to consider the stress ratio effect on the FCG rate. In order to validate the results in three random loading group with different loading levels and bandwidths, the results of the analysis, such as the mean lifetime of the specimen and the average crack length were compared with the test results in terms of the number of loading cycles.

The comparison indicated a good agreement between the results of the analysis and the test. Further, the diagrams of reliability and the probability of failure of the specimen were obtained for each loading group and were compared together.

Applying the cycle-by-cycle and CLT methods for the calculation of fatigue reliability of a CT specimen under random loading by the Walker equation and comparing their results with each other is not observed in other researches. Also in this study, the effect of the loading frequency bandwidth on lifetime was studied.