Search
Search Results
-
Monitoring of Debrecen WWTP Biogas Fermentation Processes by Chemical Methods
79-83Views:164The anaerobic digestion is a widely used economical method for sewage sludge stabilization and also purification of waste water with a high organic content. All effective anaerobic digesters transform the organic matter into biogas containing methane, which usable component covers a significant share of the heat and electricity consumption of the wastewater treatment plant (WWTP). The increasing amount of biogas is a priority task of WWTPs, which we can achieve a deeper knowledge of anaerobic digestion processes. The main task of this study is the optimization of anaerobic sludge treatment of Debrecen WWTP. Digester towers processes and their impact on the biogas yield were also priority studied.
-
Global Inversion of Pressure Dependent Acoustic Velocity Data Based on a New Rock Physical Model
47-55Views:136In this paper with the further development of our previously published single exponential model, the new multiple exponential model describing the pressure dependence of acoustic longitudinal wave velocity is presented. Since with increasing pressure in the rock several relaxation mechanisms at the same time can cause the increasing propagation velocity, the new model can handle two or more physical mechanisms (e.g. the closure of pore volume or microcracks or friction on grain boundaries etc.). The previously applied linearized inversion procedure can trap in a local minimum, so during laboratory measured longitudinal velocity-pressure data processing a global optimization method was used to find the absolute minimum. Using the developed model equation as response equation in a Simulated Annealing algorithm the petrophysical parameters of the model can be determined. Inversion results proved that the calculated data using the new model and algorithm matched more accurate with measured data on a rock sample.
-
Construction Solutions for Reducing the Effect of the Rear-end Collision
Views:147Analysing the accident statistics, we can detact that, the improvement of the transport safety is one of the most important engineering task. The number of the vehicles in the trasport gets significantly higher from year-to year, and the infrastructure of the cities frequently can not coordinate already it. Therefore the increasing of the vehicles’s number naturally involves the upgrowth of the accidents occasions too. The aim of the improvement of the vehicle-construction to reduce the personal injured and death resulted accidents number in contrast with the increasing traffic performance. This study analyses the construction options for reducing the effect of the rear-end collision whiches are concentrated for the passive vehicles and its passengers firtsly. Among the actual car manufacturers applied solutions, foward-looking possibilities and suggestions are described in this publication. The development can not be concentrated for only the safety improvement, the mass-optimalization must be completed simultenously. These apparent contrary requirements can be completed with application of new materials. Therefore the study addresses the more optimal utilization of the meatl foam in the vehicles crushbox. In addition, an optimized break-assist solution is described based on the Mercedes developed Pre Safe Plus® system to increas the abrorbtion of the impact energy.
-
Optimization and Analysis of Structure about Lifting Device of Logistics Sorting
425-431Views:159The lifting device of a logistics sorting machine needs high frequency upward and downward reciprocating motion therefore the cutting fork arms and matching parts of the shaft are often worn out. In this paper the problem of the shear fork types applied for the lifting mechanism is studied at first. Then the advanced numerical simulation software ANSYS adopted for the lifting mechanism of the shear fork type, and the means of virtual simulation is introduced. Hence the possible location of faults and fault modes are analysed. Then improving measures about the lifting mechanism of the logistics sorting machine are suggested.
-
Vehicle dynamics modelling of an electric driven race car
106-114Views:125In the following we are presenting a vehicle dynamics simulation program developed in MATLAB environment. The program is capable of calculating the dynamics functions of a vehicle from its technical data. The program has been successfully applied for the optimization of the technical data of an electric driven race car that was designed and constructed at the Department of Mechanical Engineering of the University of Debrecen.
-
Analysis of Activity Times in the Process of a Wooden Box Manufacturing
475-484Views:123The main target of companies is to earn money and achieve profit. In order to fulfil these needs, companies have to reduce their costs. Cost reduction is often associated with bad quality products, but it could be done in a different way. Sometimes it is enough to examine only their own processes and then benefit from the process optimization, process improvement or process scheduling. In this article a case study is presented, in which the differences in a production scheduling are evaluated with the application of Monte-Carlo simulation and descriptive statistics. At the end of the paper the most efficient material sequence is selected at the manufacturing company by using weighted sum model
-
Optimization of Automotive Industry’s Manufacturing Process with Lean Tools
81-89Views:360Lean plays i mportant role in industrial environment. Automotive industries use lean tools in order to reduce cost and i mprove productivity. To achieve the company's objectives and so lve the detected problems I also used lean tools. By using lean tools we want to decrease total process cost (TPC). In order to achieve this target, the three-shift production has to reduce in two-shift production, which result decrease in the human resource costs and production costs. In order to reduce shifts we have to increase overall equipment efficiency (OEE) and eliminate minimum 50% of wastes by implementing 5s methodology, using Poka-yoke and scheduled maintenance.
-
Process Innovation Tools and Strategies in Production Management
148-162Views:323The method of process innovation helps to recognize the opportunities in production processes that represent clear competitive advantage. Using it, up to 30% change is available in increasing productivity and in the reducing of costs, stocks, and lead times. There is no need for complicated methods in the process development. The power of logical, simple tools relies on the fact that everyone can learn, understand, apply them and give quick feedback about their operation. Significant changes have been made in today's possibilities of designing and operating production systems. The emergence of cyber physical systems, the opportunities offered by big data, and the "Internet of Things" (Internet of Things) have shown strong research potential for more efficient logistics and manufacturing systems. The potential of network co-operation, information gathered from tracing materials in production and communication between machines provide a wide-range of optimization opportunities for manufacturing processes. The toolkit presented in the research cannot only be used in direct production; almost all parts of the value creation process can be broken down into routine actions, so the causes of the problems can be analyzed and the development of the process’ parts can be easier implemented.
-
Mechanical Design and Finite element Analysis for Acetabular cup
23-35Views:118Hip replacements typically consist of a four-part piece. Our research will focus primarily on the acetabular component. Several different types of materials can be used when creating a hip replacement implant ranging from plastic to titanium. Different materials are used to accommodate for allergic reactions or circumventing potential health risks. Aside from the material, the size of the components plays a factor in terms of durability; a larger diameter head might avoid dislodgement though it could increase wear and tear on the stems through constant friction. A patient’s force applied to the hip replacement is usually measured through a number of physical assessments. Finite element analysis (FEA), a computer-based method of data observation, allows for us to accurately simulate hip forces and their impact on the hip replacements. Through this, it becomes easier to predict and calculate the performance of specific designs. Generative systems can also be used to support performance analysis and optimization through assessing a multitude of cases, many of which apply in real-world scenarios. By applying both systems, we designed and modeled an acetabular cup that when measured decreased the mass from 129 grams initially down to 52 grams, a 60% decrease in total mass. Furthermore, the design we created lessened the trauma on the piece through distributing force across the entirety of the piece rather than specific segments only. This shows an increased durability and life expectancy when compared to usual acetabular cups.
-
Business Strategy in the Model of Linear Activity Analysis of Production
1-14Views:171It was analyzed how the methodology of linear activity analysis of production model supports the implementation of different business strategies at a company level. Aspects of analysis are focusing on openness for markets, lean management and environmental protection strategies. The study reveals that the linear activity analysis of production – mainly due to its efficient process optimization problem solving ability – is capable supporting lean management decisions and implementing additional objectives in business strategies. Such objectives can be sustaining specific production patterns for further development or following strategies for limiting market competition. It will be shown how to quantify the costs of strategic objectives in linear activity analyzing model.