Midor Łukasz, Olszyna Grzegorz, Rokita Tomasz
et al.
This article discusses issues related to tower cranes, a group of lifting machines used in the construction industry. Vertical transport on a building site is of paramount importance, accounting for approximately 50% of all construction works. Currently, the tower crane is one of the most efficient lifting machines used in construction. It occupies minimal space on the construction site and allows for the fastest possible delivery of materials directly from the storage area to work stations, regardless of the route. This article focuses on the issues related to these devices, limiting the scope to the analysis of the rope system. The use of steel ropes in the hoisting mechanism is crucial for the reliable operation of tower cranes. The basic technical data and construction of a selected crane model chosen for the study are presented. The properties and characteristics of steel ropes used in such systems, as well as criteria for their retirement, are discussed. Subsequently, a method for modelling the rope system and simulating its operation is introduced. The use of computational tools to model the rope bending process in the hoisting mechanism allows for identifying critical points along the rope under specific operating conditions. Selected simulation results are presented in the form of tables and graphs, highlighting the areas most susceptible to wear in this type of rope mechanisms. The article concludes with practical recommendations that may enhance interest in the described method. According to the authors, the method is innovative and promising. Its application can contribute to extending the service life of ropes, facilitating procedures for monitoring their condition, and improving the safety of their use.
Sebastian Thiede, Leicai Xiao, Poorya Ghafoorpoor Yazdi
The measurement and analysis of spatially distributed ambient data (e.g. temperature, noise, lighting, or emissions) is an important aspect in factories. Ambient data is directly linked to various factory subsystems and ongoing activities and impacting operational performance, employee wellbeing, environmental outcomes, and associated costs. Due to the limited number of ambient sensor data collection points, interpolation methods are necessary to estimate ambient values at unmeasured locations, thereby generating a complete environmental distribution map. However, existing methods for analyzing spatially distributed ambient data face limitations in terms of availability, scope, and necessary efforts. The paper proposes an autonomous spatial mapping and analysis approach with multiple ambient data sources. It was validated in a factory setting with five ambient sensor data maps, and the evaluation of 12 spatial mapping methods revealed optimal interpolation techniques for different variables. This approach enables innovative manufacturing use cases with reasonable data acquisition efforts.
Detecting electrolyte leakage is an effective early warning approach for abnormal faults in lithium-ion batteries (LIBs) and can help mitigate safety risks such as fires and explosions. However, detecting electrolyte leakage in the early stages of LIB faults presents a significant challenge, as leaks in LIBs produce volatile organic compounds (VOCs) at parts per million levels that are difficult to detect using conventional VOC sensors. Here, an effective LIB VOC sensor using micro-nano optical fibres (MNFs) has been developed for the first time, coated with an in situ self-assembled zeolitic imidazolate framework-8 (ZIF-8) membrane as an electrolyte-sensitive layer. The abundance of pores in ZIF-8 is excellent for adsorbing a variety of VOCs, including diethyl carbonate, ethyl methyl carbonate, dimethyl carbonate, and propylene carbonate. The MNFs possess high refractive index sensitivity, enhancing the online monitoring of electrolytes. MNFs with a diameter of approximately 7 μm were assembled with four-cycle ZIF-8 of approximately 500 nm thickness, as the fabricated sensor. Through wavelength demodulation, the LIB sensor demonstrated high sensitivity, detecting 43.6 pm/ppm of VOCs and exhibiting rapid response and recovery times of typically within 10 min and 23 s, respectively, as well as a low theoretical detection limit of 2.65 ppm for dimethyl carbonate vapor with excellent reversibility. The first on-site verification of online LIB leakage monitoring demonstrated that the sensor achieved a 35 h early warning prior to full-load leakage, thus exhibiting promising prospects for applications in scenarios such as car batteries.
Background: Today, the digital transformation of business is one of the conditions for survival on the market. The development of digital technology is progressing rapidly, and only the business entities that keep pace with this development can expect good business results. Social entrepreneurship is an excellent way to solve the problems of social inequality and poverty and thus leads to economic growth and development. Purpose: The main goal of this research is to create a theoretical model of digital transformation of social entrepreneurship. This model can be a useful tool for deciding on the digital transformation of business. We investigated motivation of managers and employees as an influencing factor for the digital transformation of business. We declared other influencing factors as constants. Study design: We measured motivation by personal and professional use of the Internet, the acquisition of digital skills, the cost of labour of those who are involved in the digitisation process, and the application of data protection software. Ninety-seven social entrepreneurship entities from Bosnia and Herzegovina (B&H) participated in the research. The research was carried out using questionnaires, and we analysed the obtained data using correlation and regression methods. Findings: The results showed that motivation is a significant factor in the digital transformation of social entrepreneurship. Based on the results of the research, we have created a model of digital transformation of social entrepreneurship entities that can lead to economic and social development through steps applicable in practice. Limitations/future research: The most significant limitation of the research is the lack of an official register of social entrepreneurship entities from which we can collect data about the number of these entities. To future researchers, we leave open questions of other influencing factors for the development of social entrepreneurship, such as knowledge, sources of funding for initial business activities, etc.
Production management. Operations management, Personnel management. Employment management
ABSTRACTBy using Invar 36 alloy as the constituent material, a series of multi-functional metamaterials, integrating low coefficient of thermal expansion (CTE) and programmable Poisson’s ratio (PR), were originally designed and additively manufactured by laser powder bed fusion (PBF-LB). The densification, relative density, microstructures, CTE and PR were systematically characterised and analysed by experiments and numerical modelling. Specifically, the fabricated metamaterials demonstrate uniform microstructures, resulting in isotropic low CTEs ranging from 1.79 to 1.85 ppm/°C. Besides, the designed metamaterials achieve PR tuning in the range of −0.54∼+0.58, which is close to the theoretical predictions, confirming the PR programmability. The underlying mechanism is disclosed that the variable θ1 dominates the transverse deformation behaviour of the metamaterial, achieving programmable PR. Summarily, these metamaterials achieve the integration of the low CTE and programmable PR, and provide a wider operating temperature range and superior mechanical performances than polymer-based multi-functional metamaterials, exhibiting a broader application prospect.
WADED Al-Mg and Al-Mg-Sc-Zr aluminium alloy thin-wall components were produced. Heat treatment (350°C aging for 4 h) was further conducted. The effects of Sc/Zr addition on porosity, microstructure, mechanical properties and corrosion behaviour were investigated. With Sc/Zr adding, pore area fraction decreased from 0.208 to 0.005% and grain size decreased from 84.34 to 19.54 μm. In WADED Al-Mg-Sc-Zr component, microstructure showed refined equiaxed grains. Mechanical properties were improved with 360 MPa ultimate tensile strength (UTS), 185 MPa yield strength, and 23.31% elongation. After heat treatment, UTS increased to 388 MPa with good ductility (22.53%) maintained. The grain refinement and Al3(Sc, Zr) particles were the key factors for mechanical property improvement. The corrosion behaviour was improved with introduced Sc/Zr and further optimised after heat treatment. The corrosion exhibited layered characteristics due to the distribution of primary Al3(Sc, Zr) while minor-size secondary Al3(Sc, Zr) along grain boundaries improved the corrosion behaviour.
Peter Schelkens, Ayyoub Ahar, Antonin Gilles
et al.
While 60 years of successful application of holography is celebrated in this special issue, efficient representation and compression of holographic data has received relatively little attention in research. Notwithstanding this observation, and particularly due to the digitization that is also penetrating the holographic domain, interest is growing on how to efficiently compress holographic data such that interactive exchange of content, as well as digital storage can be facilitated proficiently. This is a particular challenge, not only because of its interferometric nature and the various representation formats, but also the often extremely large data volumes involved in pathological, tomographic, or high-end visualization applications. In this paper, we provide an overview of the state of the art in compression techniques and corresponding quality metrics for various practical applications in digital holography. We also consider the future by analyzing the emerging trends for addressing the key challenges in this domain.
The paper presents a comparative study of the behaviour of 97% polyamide/3% elastane socks, named functional socks, and of 70% cotton/27% polyamide/3% elastane socks, called classic socks, both type used for moderate-intensity physical activity. Nowadays, the question always arises about what socks to wear: classic 100% cotton socks, cotton/polyamide/elastane socks, or polyamide/elastane socks. The wearing comfort of the socks is the determining factor in choosing the optimal variant. The functional socks are made of 100% synthetic yarns and are appreciated due to the properties of absorption and rapid transfer of moisture from the body to the environment. The classic socks are made of cotton or cotton yarns mixed with synthetic yarns, giving better wearing comfort compared to functional socks through the high moisture absorption capacity. But due to the small capacity to transfer moisture from the body to the outside environment, wearing for a long time can produce discomfort as a result of the humid environment that is created. The two types of socks were evaluated through a series of analyses as follows: weight per piece, optical microscopy, hygroscopicity, hydrophilicity, elasticity in the direction of stitches’ rows and degree of compression. The analysed data led to the conclusion that functional socks have superior elasticity and comfort properties compared to the classical ones.
This paper presents the technological process of manufacturing a men sports shoe product, in the IL system. The paper begins with the presentation of the technological process of manufacturing the product as an assembly, followed by detailing in a case study the specific operations, but also the common ones, which are carried out during the process. In the case of this model, the order of operation of the technological process is given by the method of joining the top with the upper but also by the type of the linings.
The technological process presents the method of assembling the component parts of the upper assembly, the equipment used, the time norm and the production norm. In conclusion, we can say that a special role in obtaining a production both qualitative and quantitative represents the way the production is organized, the maintenance of the machines, the optimal use of the production capacity, so as to ensure a continuous flow of production. The production launch is made according to the adopted manufacturing program, and this is done in correlation with the production capacity and the quantity of the finished product that will reach the beneficiary.
In this paper, the problem of scheduling jobs with non-identical sizes has been studied on a single-batch processing machine, in order to minimize the makespan. Using new lower bounds, a branch and bound algorithm has been proposed to solve the problem. In this algorithm, two new methods have been used to generate lower bounds and results have been compared with the existing lower bound in literature. In order to evaluate the performance of the proposed method, test problems have been randomly generated and branch and bound algorithm has been tested with different lower bounds on these cases. Findings indicated that when the size of the jobs is large compared to the capacity of the machine, the branch and bound algorithm with the new lower bound has the best performance. When the size of the jobs is small compared to the capacity of the machine (up to half the capacity of the machine), the algorithm with existing lower bound has better performance. In addition, when the size of the jobs is neither large nor small, the lower bounds provide the best performance.
<strong>Introduction: </strong>Based on predictions, services are a key component of the growth of the global economy in future (Arnold et al. 2011). Acording to Jane and Kumar (2012), services play a critical role in a supply chain. Also, according to Wang et al. (2015), a "product" or "service" must exist in each supply chain which is produced by the upstream sectors and delivered to downstream. Recently due to increasing customer expectations, companies’ competition has been replaced by the supply chains competition and as a result, competition has been increased in the simultaneous supply of products and services. This has led to challenges in integrating companies and in coordinating the materials, information and financial flow that were previously overlooked. Accordingly, a new managerial philosophy has been developed known as Product-Service Supply Chain (PSSC) (Stanley & Wisner, 2002). This study seeks to develop a performance evaluation model for the product-service supply chain in the home appliance industry, which is finally solved using Adaptive Neuro-Fuzzy Inference System (ANFIS).
<strong>Design/Approach: </strong>In this paper, performance evaluation constructs and criteria of service supply chain are identified by reviewing the literature and exploratory and confirmatory factor analysis and then, the performance evaluation of service supply chains in Iran's home appliance industry has been performed using these constructs, criteria and ANFIS.
<strong>Findings and Discussion: </strong>Based on the findings, ten main extracted constructs can be suggested for the performance evaluation of the supply chain. They include "Operational Performance (OP)", "Strategic Performance (SP)", "Financial Performance (FP)", "Performance of Information and Communication Technology (PICT)", “Return Performance” (REP), “Risk Performance (RIP)”, “Logistic Performance (LP)”, “Market Performance (MP)”, “Internal Structure Performance (PIS)” and “Growth and Innovation Performance (PGI)”, among which, the Strategic Performance (SP) and Return Performance (REP) are the most important and the least important constructs, respectively.
<strong>Conclusions</strong>
Based on the findings, the following practical recommendations are suggested to the companies:
Enhancing the demand forecasts performance and utilizing more appropriate methods and software to improve forecasts in demand and order management areas.
Improving the return management status by increased attention and more investment in return management processes.
Effective investment in service development management to enhance the R&D services performance.
Utilizing risk management approaches and methods to identify and take preventive actions on the risks in the companies’ service supply chain.
<strong>References</strong>
Arnold, J.M., Javorcik, B.S., & Mattoo, A. (2011). “Does services liberalization benefit manufacturing firms? evidence from the Czech Republic”. <em>Journal of International Economics</em>, 85(1), 136-146.
Azar, A., Gholamzadeh, R., & Ghanavati, M. (2012). <em>Path-Structural Modeling in Management: SmartPLS Application</em>, Tehran: Publishing Knowledge Look.
Rezaei Moghadam S., Yousefi, O., Karbasisan, M. and Khayambashi, B. (2018). “Integrated production-distribution planning in a reverse supply chain via multi-objective mathematical modeling; case study in a high-tech industry”. <em>Production and Operations Management</em>, 9(2), 57-76.
Zhou, H., & Benton, W. C. (2007). “Supply chain practice and information sharing”. <em>Journal of Operations Management</em>, 25(6), 1348-1365.
Management. Industrial management, Production management. Operations management
Penelitian ini bertujuan untuk menguji peringkat perusahaan berdasarkan ASEAN corporate governance scorecard, sebagai variabel pemoderasi, atas pengaruh kepemilikan asing terhadap nilai perusahaan di ASEAN. Sample penelitian terdiri dari 491 perusahaan manufaktur yang terdaftar di pasar modal Thailand, Singapore, Philippines, Indonesia, and Malaysia tahun 2012-2013. Dengan analisis white-regression, penelitian ini menemukan bahwa peringkat 50 tertinggi ASEAN corporate governance scorecard memoderasi pengaruh kepemilikan asing terhadap nilai perusahaan. Skor tinggi ASEAN corporate governance scorecard; sebagai peningkatan hak pemegang saham, kesetaran pemegang saham, peran pemangku kepentingan, pengungkapan dan transparansi, serta tanggung jawab dewan; meningkatkan peran pemegang saham asing dalam meningkatkan nilai perusahaan. Manajemen dapat membuat kebijakan mengenai kepemilikan asing juga corporate governance yang optimal, sehingga manajemen dapat meningkatkan kesejahteraan pemegang saham melalui peningkatan nilai perusahaan. Investor yang tertarik berinvestasi di luar negeri, khususnya di ASEAN, harus memperhatikan kondisi corporate governance perusahaan, sehingga kesejahteraan investor dapat meningkat.
Kata Kunci: ASEAN corporate governance scorecard, kepemilikan asing, nilai perusahaan.
Production management. Operations management, Management. Industrial management
In memoriam of Dr. H. Peter STEINHAGEN
Although the increasing economic importance of Eucalyptus lumber to furniture and other value added products manufacturing, its industrial use is still small. One of the main reasons is the difficulty to dry the lumber and related loses of row material. There is a general recommendation in literature to use a low drying rate in initial stages of the process, and changing to a more aggressive drying after removal of liquid water from the lumber. According classical theory about drying of porous material, this point should coincide with the predominance of diffusion phenomena in the moisture movement; which could be determined through the characteristic drying curve of the material. With the objective to get better knowledge about the drying of Eucalyptus grandis lumber, its characteristic drying curve was determined, and the results proved that Eucalyptus grandis lumber is not permeable to liquid flow. Based on its characteristic drying curve, it is possible to suggest the change of drying conditions when lumber moisture content, dry basis, is between 35% and 40%, then starting a more aggressive drying.
The assignment of personnel to the right positions in order to increase organization's performance is one of the most crucial tasks in human resource management. In this paper, personnel assignment problem is formulated as a multi-objective binary integer programming model in which skills, level of satisfaction and training cost of personnel are considered simultaneously in productive company. The purpose of this model is to obtain the best matching between candidates and positions. In this model, a set of methods such as a group analytic hierarchy process (GAHP), Shannon entropy, coefficient of variation (CV) and fuzzy logic are used to calculate the weights of evaluation criteria, weights of position and coefficient of objective functions. This proposed model can rationalize the subjective judgments of decision makers with mathematic models.
Management. Industrial management, Production management. Operations management
In the article there were presented chosen issues of quality management. Important role of information and work processes in companies were emphasized . Based on eight rules of quality management, TQM standards and ideas of discipline pioneers like Deming, Juran, Crosby and Shewart, author has constructed way of using chosen rules and assumptions to company`s information circulation. Analogy, suggested by author, has not only emphasized importance of information as a company`s resource, but also has pointed to possibility of improving ways of managing this information.
Tannin extracts were prepared from barks of maritime pine (Pinus maritimus), aleppo pine (Pinus halepensis), Norway spruce (Picea abies) and from a mixture of barks of different pine species (Pinus spp., namely 20% black pine (Pinus thunbergii)+ 30% Scots pine (Pinus sylvestris) + 20% maritime pine (Pinus maritimus) + 10% Aleppo Pine (Pinus halepensis) + 5% Douglas fir (Pseudotsuga menziesii) + 15% Norway spruce (Picea abies)) at a paper mill. The 13C-NMR spectra were carried out from these tannins. Blending systems adhesives were prephe increase number of smaller bands between 20 and 65 ppm clearly indicate that the extraction of procyanidin-type tannins has been incorrect yielded high relative proportions of catechinic acid structures and diarylpropanol-catechinin acid dimer caused by internal flavonoid rearrangement, and causing the blockage of the C6 and C8 reactive sites, rendering unusable the tannin for wood adhesive applications. Thus, the gel times are very long except for the maritime pine tannin with a value of 51 (s). The TMA analysis gave very low MOE values for almost all the tannin extract samples, except for maritime pine. This situation was confirmed by the IB test. Only maritime pine tannin presented a good mechanical resistance with a value of 0.6 (MPa). Only this sample fulfils the standard requested.