Author(s):  
Goharik Petrosyan ◽  
Armen Gaboutchian ◽  
Vladimir Knyaz

Petri nets are a mathematical apparatus for modelling dynamic discrete systems. Their feature is the ability to display parallelism, asynchrony and hierarchy. First was described by Karl Petri in 1962 [1,2,8]. The Petri net is a bipartite oriented graph consisting of two types of vertices - positions and transitions connected by arcs between each other; vertices of the same type cannot be directly connected. Positions can be placed by tags (markers) that can move around the network. [2] Petri Nets (PN) used for modelling real systems is sometimes referred to as Condition/Events nets. Places identify the conditions of the parts of the system (working, idling, queuing, and failing), and transitions describe the passage from one state to another (end of a task, failure, repair...). An event occurs (a transition fire) when all the conditions are satisfied (input places are marked) and give concession to the event. The occurrence of the event entirely or partially modifies the status of the conditions (marking). The number of tokens in a place can be used to identify the number of resources lying in the condition denoted by that place [1,2,8]. Coloured Petri nets (CPN) is a graphical oriented language for design, specification, simulation and verification of systems [3-6,9,15]. It is in particular well-suited for systems that consist of several processes which communicate and synchronize. Typical examples of application areas are communication protocols, distributed systems, automated production systems, workflow analysis and VLSI chips. In the Classical Petri Net, tokens do not differ; we can say that they are colourless. Unlike standard Petri nets in Colored Petri Net of a position can contain tokens of arbitrary complexity, such as lists, etc., that enables modelling to be more reliable. The article is devoted to the study of the possibilities of modelling Colored Petri nets. The article discusses the interrelation of languages of the Colored Petri nets and traditional formal languages. The Venn diagram, which the author has modified, shows the relationship between the languages of the Colored Petri nets and some traditional languages. The language class of the Colored Petri nets includes a whole class of Context-free languages and some other classes. The paper shows modelling the task synchronization Patil using Colored Petri net, which can't be modeled using well- known operations P and V or by classical Petri network, since the operations P and V and classical Petri networks have limited mathematical properties which do not allow to model the mechanisms in which the process should be synchronized with the optimal allocation of resources.


2020 ◽  
Vol 11 (1) ◽  
pp. 054
Author(s):  
José Antonio De Miranda Lammoglia ◽  
Nilson Brandalise ◽  
Cecilia Toledo Hernandez

The scenario of global competitiveness demands more and more of the organizations the search for continuous improvement. For survival, in the face of adverse market conditions, modern production management strategies are essential to make production processes increasingly efficient, lean and sustainable, minimizing losses in their production systems. In this sense, when thinking about changes in production lines, in search of improvements in their process, criteria that provide Benefits, Opportunities, Costs and Risks (BOCR) should be considered. In this way, managers and executives should rely on tools and methods that allow them to guide their decisions in a clear way. The objective of this work is to apply a method of Decision Making with Multiple Criteria to the alternatives of investment projects in production lines in Lean Manufacturing concept. As a general result, it was possible to observe the applicability of the AHP BOCR method for the decision-making case involving several criteria and subcriteria for choosing the Lean investment project in the steel environment, the preferred alternative being the discontinuity of the production line 1 and the absorption of their respective production volume by production lines 2 and 3 through investments in them.


2014 ◽  
Vol 1018 ◽  
pp. 571-579
Author(s):  
Günther Schuh ◽  
Thomas Gartzen ◽  
Felix Basse

Reliable and accurate predictions on future states of production systems are the objective of production theories. In this paper, the authors determined shortcomings of current deterministic models and traced them back to the poor theoretical basis of scientific research in the area. The observations resulted in the development of the conceptScientific Management 2.0as an appropriate research methodology for production management. This new empirical approach takes into account three requirements to scientifically precise investigations: It expands existing theory by socio-technical aspects, uses embedded experiments as a profound basis for investigation and provides a design that warrants the methodical exactness required. RWTH Aachen’sDemonstration Factoryrepresents an adequate infrastructure to prove feasibility and performance of the new approach.


2015 ◽  
Vol 10 (1) ◽  
pp. 71
Author(s):  
Tugimin Tugimin

ABSTRACT The craft of a leather puppet in the district Bantul, Province Yogyakarta Special Region in its development experienced tides. Success retreival craft leather puppet skin strongly influenced by among other things, trend with the market demands quality goods, distinctness, value and price. But there is a vital need reckoned that human resources leather puppet characters handicraftsman skin also had an influence upon the way forward in sell their products. So far the role of the craftsman and forced them to market own goods their craft. Idealism character basic craftsman who pushes art of performing this function as artists and forced them role as an entrepreneur craft skin. It is very prevalent business does craft leather puppet skin and entrepreneurs craft leather puppet, eliciting much problem because tends perpetrated by player singular in do everything in good for production, management, marketing, etc. The development of crafts leather puppets are not limited on the orientation of the sheer capital adequacy but also the need for innovation, improvement of production systems, design, quality control, management, marketing system, that it took an understanding of entrepreneurship that is able to equip a small craftsmen as a good businessman. Keywords: character of human resources, marketing, business success. ABSTRAK Perkembangan kerajinan wayang kulit di Kabupaten Bantul, Propinsi Daerah Istimewa Yogyakarta cukup menyerap tenaga kerja. Keberhasilan usaha jenis ini perlu diimbangi dengan karakter sumber daya manusia dan kemampuan pegelolaan usaha yang baik agar dapat menangkap peluang pasar. Hanya saja selama ini sektor informal masih banyak kelemahannya karena para pengrajin merangkap kerja dalam segala urusan mulai dari pengerjaan produksi, manajemen, dan sekaligus pemasarannya, karena mereka belum memiliki pemahaman kewirausahaan yang baik. Untuk itulah perlu menjadi perhatian bersama agar sector ini dapat berkembang dengan baik untuk menangkap dan menjajagi pasar guna menjamin kelangsungan usahanya. Kata kunci: karakter pelaku usaha, pemasaran, keberhasilan usaha.


Author(s):  
A.N. Sochnev

The paper describes the approach to solving the problem of optimal planning of the production process. A discrete production system represented by the operations of machining, welding and painting was chosen as the object of research. The study states the problem of optimization of assembly production, which contains a typical criterion of optimality. A mechanism for meeting the criterion using a simulation model based on a Petri net is determined. The rules for developing feedback on the state of the network model and a method for controlling the simulation of the Petri net based on the analysis of its states are given. A binary function is used to analyze the states of the model. The developed approach to process optimization develops the theory of Petri nets, makes it more suitable for modeling complex systems with a branched structure and a large number of interconnections, which is a typical situation for production systems. The most universal approaches of control theory, e.g. feedback principle, are used, which implies a significant degree of universality and replicability of the approach. On the basis of the developed theoretical provisions, a test example is presented that characterizes the effect of their application. The presence of assembly production at most mechanical-engineering enterprises determines the high practical significance of the developed approach


2020 ◽  
Vol 12 (22) ◽  
pp. 9781
Author(s):  
Elisabeth Viles ◽  
Javier Santos ◽  
Tamara Fernández Arévalo ◽  
Martín Tanco ◽  
Florencia Kalemkerian

In a circular economy (CE) environment, it is important to make good and efficient use of resources and consider that the waste generated in production processes can be a valuable resource. However, the tools and methodologies conventionally used to analyze and evaluate production systems are based on techniques focused on linear production management models, where the primary purpose is to reduce the treatment and management of waste as much as possible and where productive and environmental efficiency are not evaluated simultaneously. Changing the paradigm from a linear to a circular economy requires that a new strategy for production systems be defined, one that makes production processes simultaneously circular and efficient (in terms of quality and productivity). In this context, a holistic vision is needed when implementing CE strategies. Therefore, the main aim of this paper is to provide evidence, through two real case studies in the use of water, that the management of this resource without considering systemic thinking may not be the most circular solution. Main results showed that improvements based on the traditional approach of reducing resource use cannot provide the best results if they are supported only by current process consumption without considering the circularity of resources.


HortScience ◽  
2018 ◽  
Vol 53 (9) ◽  
pp. 1364-1371 ◽  
Author(s):  
John C. Majsztrik ◽  
Andrew G. Ristvey ◽  
David S. Ross ◽  
John D. Lea-Cox

Quantifying the range of fertilizer and irrigation application rates applied by the ornamental nursery and greenhouse industry is challenging as a result of the variety of species, production systems, and cultural management techniques that are used. To gain a better understanding of nutrient and water use by the ornamental industry in Maryland, 491 potential operations (including multiple addresses and contacts) in the state were mailed a packet of information asking for their voluntary participation. Of the 491 potential operations, it was determined that 348 operations were currently in operation. Of those 348 operations, 48 (14% of the operations in the state) participated in a site visit and an in-depth interview, and a detailed site analysis of the water and nutrient management practices was performed on a production management unit (MU) basis. The authors define an MU as a group of plants that is managed similarly, particularly in regard to nutrient and irrigation application. Greenhouse operations reported, on average, 198, 122, and 196 kg/ha/year of nitrogen (N), phosphorus (P, as P2O5), and potassium (K, as K2O) fertilizer used, respectively, for 27 operations, representing 188 MUs. Twenty-seven outdoor container nursery operations had a total of 162 MUs, with an average of 964, 390, and 556 kg/ha/year of N, P2O5, and K2O fertilizer used, respectively. Field nursery (soil-based) operations were represented by 17 operations, producing 96 MUs, with an average of 67, 20, and 25 kg/ha/year of N, P2O5, and K2O fertilizer used, respectively. Irrigation volume per application was greatest in container nursery operations, followed by greenhouse and field nursery operations. Data were also analyzed by creating quartiles, which represent the median of the lowest 25%, the middle 50%, and highest 75% of values. It is likely that the greatest quartile application rates reported by growers could be substantially reduced with little to no effect on plant production time or quality. These data also provide baseline information to determine changes in fertilization practices over time. They were also used as inputs for water and nutrient management models developed as part of this study. These data may also be useful for informing nutrient application rates used in the Chesapeake Bay nutrient modeling process.


2020 ◽  
Vol 12 (9) ◽  
pp. 3791 ◽  
Author(s):  
Olumide Emmanuel Oluyisola ◽  
Fabio Sgarbossa ◽  
Jan Ola Strandhagen

Many companies are struggling to manage their production systems due to increasing market uncertainty. While emerging ‘smart’ technologies such as the internet of things, machine learning, and cloud computing have been touted as having the potential to transform production management, the realities of their adoption and use have been much more challenging than anticipated. In this paper, we explore these challenges and present a conceptual model, a use-case matrix and a product–process framework for a smart production planning and control (smart PPC) system and illustrate the use of these artefacts through four case companies. The presented model adopts an incremental approach that companies with limited resources could employ in improving their PPC process in the context of industry 4.0 and sustainability. The results reveal that while make-to-order companies are more likely to derive greater benefits from a smart product strategy, make-to-stock companies are more likely to derive the most benefit from pursuing a smart process strategy, and consequently a smart PPC solution.


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