Characteristics Of Production Process Research Articles

NBG-17 – An improved graphite grade for HTRs and VHTRs

NBG-18 is an established nuclear graphite grade for moderator and reflector applications in gas-cooled nuclear reactors. Prismatic-type reactors however require a material with lower maximum grain size due to the rather small spacing between cooling channels in the fuel block. With NBG-17, a suitable material is developed using same proven raw materials and process route, including vibromoulding forming process. Production process and material characteristics are described, demonstrating the general suitability for nuclear application, with irradiation tests in progress.

Intelligent Operation Control for the Fused Magnesia Production

An electro-fused magnesia furnace (EFMF) is used to produce electro-fused magnesia. Due to the complex dynamic characteristics of the EFMF production process, it is difficult to achieve the satisfactory control performances only by the independent conventional control method. As a result, the lower loop control with manual operations is still widely used in practice. However, the manual operation cannot ensure that the actual production qualities and the energy consumption of unit production meet the technical requirements all the time. In this paper, an intelligent operation control strategy is developed for the EFMF to automatically adjust the setpoints of the lower level control system. Based on the proposed intelligent control strategy, an intelligent control system for the EFMF is built and implemented on site. Industrial application has demonstrated that the intelligent control system can achieve reliable, accurate and timely control performances.

The Production Scheduling Problem of Aluminum Casting Based on Theory of Constraints

Based on explaining characteristics of aluminum production process and management, this paper built a production scheduling model of the aluminum casting with its equipment constrains and process constraints, discussed the optimization strategy of the production scheduling for aluminum casting.

Multi-Stage Production Planning Modeling of Iron and Steel Enterprise Based on Genetic Algorithm

In accordance with the main flow characteristics of steel and iron production process, some problems are analyzed coming from the making, performance and feedback of the production planning of iron and steel business enterprises in this paper. By using operation research theories and genetic algorithms, one advanced planning model of iron and steel productions suitable of various circumstance and environments is established to set up on the factor of the segment and environment variety. Penalty function is adopted in the course of getting solution. These parameters of scale of father population, crossover probability, mutation probability and penalty factor are combined and optimized. At the same time, to improve these algorithms and the solution process actually, some optimized models and projects were put forward from some plans on the basis of collecting information. It accords with the actual conditions of this enterprise basically that the optimization solution to production plans of real iron and steel enterprise by using the algorithm.

Manufacturing cost estimation for steel product based on consumption chain: a case study in China

The paper proposes a cost estimation method which is fitted to continuous production process of iron and steel product. In order to get the steel product price and cost control target before production, estimating steel product cost accurately is very important for iron and steel enterprise. Feature costing is a topic of recent discussion related to cost management system aimed at understanding how product features influence production process costs. In this study, after analysing the existing cost estimation methods, the consumption chain model for iron and steel enterprise is constructed. Steel product cost estimation method was given based on steel product features and process characteristics. Product features were extracted from the order information and consumption chain was automatically generated by matching the product features and manufacturing process chain. Raw material cost and activity cost for steel product were calculated by analysing consumption chain. Finally, the cost estimation method was demonstrated through an application in a steel enterprise of China. Results show that the proposed cost estimation method based on consumption chain model is able to accurately estimate the costs of steel products.

Research on Underground Coal Mine Production Process Analysis and Informatization

This article analyzes the characteristics of underground coal mine production process, and compares underground coal mine production process with discrete type and continuous type production processes. On this basis, it investigates the construction and implementation countermeasures on underground coal mine information system.

GROWING GREEN: THE EMERGENT ROLE OF NON-TILAPIA ATTRIBUTES IN MARKETING TILAPIA

This paper is focused upon the emergent emphasis of environmentally friendly (ENVF) attributes in fish with particular regard to tilapia in the UK. The focus is upon the technical production issues, marketing implications, public health and adoption responses from a 3-year multi-disciplinary Research Councils UK project, which examined the prospects for UK (agricultural) farmers to diversify into production of warmwater tilapia. The proposed production process and product characteristics abound with green credentials, consistent with emergent market demands. This combination might enable small-scale producers to access growing UK niche markets for fresh fish and to compete through upmarket positions with expanding EU tilapia imports. Having ascertained the wider market characteristics, primary research was undertaken through consumer focus groups and in-depth interviews with organizational channel members. The results supported the initial premise of niche markets existing for tilapia produced from local, small-scale environmentally friendly units. Three target groups in the UK were identified: ethnic consumers, green consumers and discrete segments (gastro-pubs and upscale fish restaurants) within foodservice. Having established favorable market prospects the propensity of farmers to diversify into this novel area of activity was explored. Investigation of farmer entrepreneurship, undertaken in 2006 and 2007, explored perceived challenges in the new aquaculture venture. In-depth face to face and telephone interviews with agricultural farmers identified a number of factors that both encouraged and dissuaded them from diversification into tilapia. Despite the ongoing interests of some, and other emergent adopters, the majority seem disinclined to commercialize their interest. The paper concludes that a more holistic support perspective will be required to promote a more favorable reaction and reviews the prognosis for the success of local fish production.

The Demand for Seafood Eco-Labels in France

The French fishing industry has a long history and its seafood market a wide variety of products. Despite the worldwide growth in ecolabelling schemes over the past decade, the French industry has only very recently shown an interest in such schemes. Growing consumer and retailer awareness of environmental issues in France has changed the situation and it is now of interest to look at the demand for seafood ecolabelling in relation to the public perception of commercial fishing.We analyse, using an ordered Probit model, the factors influencing consumer demand for seafood ecolabelling on the basis of a French survey carried out on more than 1000 consumers. Our results show a significant relationship between the acceptability of ecolabelling and certain purchase criteria. The production process characteristics in (origin, wild vs. farmed, level of natural stocks) impact more strongly on the demand for ecolabelling than product attributes (form, visual appeal, freshness). Consumers are also influenced more by regulation than by information, inaccurate or otherwise, they may have about the fishing industry. Finally, our analysis confirms a higher demand for ecolabelling from young, educated consumers, particularly those living in non-coastal areas.

Multi-Objective Flexible Job-Shop Scheduling Problem in Steel Tubes Production

Abstract On the basis of the distinct characteristics of steel tube production process, the production scheduling problem of seamless steel tubes is described as flexible job-shop scheduling problem. Considering the parallel machines with capacity and speed constraint, maintenance of machines as well as intermediate inventory restriction, it is formulated as mixed-integer-programming(MIP) model to decide the flexible routes for every job and to optimize the sequence of jobs. The objective is not only to reduce delivery delay, but also to minimize idleness of machines and interruption in production. Given the problem is NP-hard (non-deterministic polynomial-time hard), modified genetic algorithm is proposed, whose effectiveness can be well verified in scheduling decision support system for the production of seamless steel tubes in Baoshan Iron & Steel Complex.

Modelling the relationship between product quality and process characteristics in process industry: an application

Process industries have a relatively sophisticated and high capital density structure in manufacturing industries. Process industries are one of the leading industries having competitive advantage due to specialisation, huge amount of standard production and scale economies. In this paper, the goal programming (GP) technique is applied for quality improvement in beer manufacturing as an example of process industry. The main purpose of the constructed model is to determine the new and current standards of the manufacturing process variables, which affect the characteristics of product quality. The model is, basically, formed in three phases. The first is concerned with multiple-regression equations. In this phase, product characteristics are defined as dependent variables while the manufacturing process variables are defined as independent variables. In the second phase, the GP technique is applied to these equations and to other objective functions. In the last phase, the solution values obtained are used to redefine tolerances of variables called process control variables.

Systems biotechnology of mammalian cell factories

The increasing demand for recombinant therapeutic proteins has placed significant pressure on the biopharmaceutical industry to develop high-yielding, mammalian cell-based production systems. Current efforts to increase the production of recombinant proteins by mammalian host cells largely proceed by the lengthy screening of clonal derivatives rather than by directed genetic or metabolic engineering. However, the advent of systems biology has created a new set of tools that will ensure that future engineering strategies will be informed by an understanding of the genetic/regulatory and metabolic networks that determine the functional competence of mammalian cell factories in vitro. In this review we summarize recent systems-level studies that utilize genome-scale analytical tools to analyse the functional basis for key production process characteristics such as high cell-specific productivity, correct product processing and rapid cell proliferation in the in vitro environment. We also describe the use of high-throughput -omic technologies to investigate how mammalian cell factories respond to environmental and metabolic perturbation.

MILP-based campaign scheduling in a specialty chemicals plant: a case study

Supply chain management in chemical process industry focuses on production planning and scheduling to reduce production cost and inventories and simultaneously increase the utilization of production capacities and the service level. These objectives and the specific characteristics of chemical production processes result in complex planning problems. To handle this complexity, advanced planning systems (APS) are implemented and often enhanced by tailor-made optimization algorithms. In this article, we focus on a real-world problem of production planning arising from a specialty chemicals plant. Formulations for finished products comprise several production and refinement processes which result in all types of material flows. Most processes cannot be operated on only one multi-purpose facility, but on a choice of different facilities. Due to sequence dependencies, several batches of identical processes are grouped together to form production campaigns. We describe a method for multicriteria optimization of short- and mid-term production campaign scheduling which is based on a time-continuous MILP formulation. In a preparatory step, deterministic algorithms calculate the structures of the formulations and solve the bills of material for each primary demand. The facility selection for each production campaign is done in a first MILP step. Optimized campaign scheduling is performed in a second step, which again is based on MILP. We show how this method can be successfully adapted to compute optimized schedules even for problem examples of real-world size, and we furthermore outline implementation issues including integration with an APS.

Environmental Certification of Forests in Mexico: The Political Ecology of a Nongovernmental Market Intervention

The certification of the environmental and social characteristics of a product's production process is emerging as a significant transnational, nongovernmental, market-based approach to environmental regulation and development. Using conventions analysis and commodity network analysis, this article examines the political ecology of one such market intervention. After only a decade, environmental certification of forests has spread to cover a significant portion of the world's logged forests, major wood retailers increasingly require it, and international environmental organizations strongly support it. In Mexico, where 12 percent of the wood harvest is certified, certification requires forest managers to make substantial improvements to the social and environmental aspects of forest management. Actors in the Mexican wood commodity network include forest villagers, forest managers, wood processors, government regulators, and transnational wood retailers. These actors express an array of environmental concerns, social values, and interests in price and market share. The big retailers, however, are the most powerful actors in the commodity network, and their demands for high volumes and low prices dominate. As a result, forest certification has so far failed to generate prices that permit forest managers to cover the costs of certification and its required forest management improvements; the instrument imposes requirements on southern producers without rewarding them for their increased efforts. In addition to the equity issues, these features of the commodity network limit the adoption of forest certification—and the forest management improvements it generates—to only the largest forest management operations in Mexico. The case of Mexico suggests broader limitations to nongovernmental, market-based approaches to environmental governance and development. These need to be less naïve about the ability of product certification to insert values in markets governed by powerful actors like retailers. Including rules modeled on Fair Trade will extend their reach, equity, and efficacy; nevertheless, voluntary market-based instruments cannot replace a more direct government role in environmental regulation and development projects.

The Spread of Contingent Work in the Knowledge-Based Economy

Permanent employment, typical of industrial societies and bolstered by numerous social guaranties, has been declining in the past 2 decades. There has been a steady expansion of various forms of contingent work. The decomposition of traditional work is a logical consequence of the characteristic patterns of the knowledge-based economy. According to the logic of information technology, changeable modules are key characteristics of production processes and economic organizations. Each module leads a life of its own, with infinite combinatory possibilities. As a consequence, static and “safe” economic arrangements are replaced by dynamic and uncertain institutions. Employees (except for key personnel) become interchangeable, disposable, recallable, and transferable. Consequently, the portfolio of workers’ capabilities and knowledge should be adjusted to the requirements of changing workplaces. For companies, the return on investments in employees’ knowledge is uncertain; thus, contingent workers have to undertake, at least partly, the responsibility and costs of their own training.

The planning flexibility bottleneck in food processing industries

Production planners in food processing industries must continuously balance efficient production with flexible performance. On the basis of case studies, we state that flexibility is not only restrained by hard-wired production process characteristics, but also by organizational procedures in the planning process. Planning practice in food processing industries is often not able to make the most of the available flexibility in the production processes, and our analysis shows that existing production planning approaches, ERP systems, and advanced planning systems can only partly resolve this. We propose a planning framework that can help to analyze the flexibility of the planning. The planning framework relates planning events to the way in which planning decisions are structured in the planning organization.

Comparison of OR and AI methods in discrete manufacturing using fuzzy logic

Since 1950s the techniques of Operations Research (OR) and Optimization have been utilized to increase the efficiency of the production systems. With the widespread use of computers, it has even become easier to deal with industrial problems. However the complexity of the problems still reveals the difficulty in providing solutions. The use of artificial intelligence (AI) seems to attract the attention of the researcher to overcome to the difficulties. This has already been realized with several successful applications. In this study, the use of AI and OR techniques is compared using fuzzy logic. The progress of manufacturing systems, characteristics of production processes, system managements and system behavior are taken into account. The study is focussed on only discrete manufacturing.

Aplicação das técnicas de planejamento e análise de experimentos no processo de injeção plástica

Experimentos industriais são realizados pelas empresas com o intuito de melhorar o desempenho dos produtos e os processos de fabricação. Nesse sentido, este trabalho tem por objetivo estudar e aplicar as técnicas de planejamento e análise de experimentos na melhoria da qualidade industrial. Especificamente são aplicadas as técnicas de planejamento Fatorial Fracionado 2k-p, Metodologia de Superfície de Resposta e Análise de Variância, em um processo de moldagem por injeção plástica. Com essa pesquisa experimental foi possível identificar os níveis ótimos de regulagem e os parâmetros mais importantes da injeção plástica: temperatura da máquina e pressão de injeção. Para finalizar é avaliado o procedimento de implementação das técnicas de experimentação e as dificuldades práticas encontradas na empresa.

Electric power supply in an offshore oil production platform

A study of the provision of electric power using associated natural gas as primary source of energy, in an offshore oil production platform has been carried out. Some of the problems to be contended with include: the effects of impurities contained in the fuel gas supply;variations in the production process characteristics; space constraints and the fire hazards that exist in an oil production environment. The study revealed that power supply can be improved by modifying fuel gas supply manifold, and also by introducing multiple stage gas filteration units and neutralizer filter units. Finally, among other recommendations, it will be desirable to replace the battery-powered UPS system with a rotary engine UPS which can provide long-term power supply back-up as well as the benefits of rotating machines. KEY WORDS: Offshore, Platform, Power Supply, Gas turbine, Rotary Diesel UPS. [Global Jnl Engineering Res. Vol.2(1&2) 2003: 35-40]

On characteristics of production and destruction processes in lowland and mountain tundras of the extreme north.

Parameters of the production and destruction processes in different types of tundras are compared. It is shown that there is a fairly high degree of correspondence between the structure of tundra communities and the ecotopes occupied by them. On the other hand, typologically similar lowland and mountain tundras markedly differ in the functional respect. The rate of decomposition processes is higher under environmental conditions of the mountain tundra belt.

A decision support system for cellular manufacturing system design

With the growth of competitive pressure in the global markets, there has been an increase in demand in industry for cellular manufacturing systems (CMSs) in order to improve productivity and process flexibility. The design of CMSs for industrial applications is a complex and knowledge intensive process as it involves the consideration of many factors including production data and process characteristics. This paper describes the development and implementation of a decision support system for the feasibility and conceptual design of CMSs. The system is based on the knowledge-based system approach, and is able to make recommendations of system feasibility, cell formation techniques and cell types. A case study is also presented to demonstrate the capability of the decision support system.