Search results

Filters

  • Journals
  • Date

Search results

Number of results: 289
items per page: 25 50 75
Sort by:

Abstract

Redundancy based methods are proactive scheduling methods for solving the Project Scheduling Problem (PSP) with non-deterministic activities duration. The fundamental strategy of these methods is to estimate the activities duration by adding extra time to the original duration. The extra time allows to consider the risks that may affect the activities durations and to reduce the number of adjustments to the baseline generated for the project. In this article, four methods based on redundancies were proposed and compared from two robustness indicators. These indicators were calculated after running a simulation process. On the other hand, linear programming was applied as the solution technique to generate the baselines of 480 projects analyzed. Finally, the results obtained allowed to identify the most adequate method to solve the PSP with probabilistic activity duration and generate robust baselines.
Go to article

Abstract

The focus of this paper is to propose a method for prioritizing knowledge and technology factor in companies’ business strategy. The data has been gathered and analyzed from Malaysian-owned company of medium size type industry, employing around 250 employees and listed in the Malaysian Bourse Stock of Exchange, since 2000. Sense and respond model is used to determine competitive priorities of the firms. Then knowledge and technology part of sense and respond questionnaire is used to calculate the variability coefficient i.e. the uncertainty caused by technology and knowledge factor. The results show that the company is not leading in term of technology (spear head technology share is around 33%). Therefore, the enhancement of technology and knowledge to SCA values is not significantly seen in this study. The usage of the core technologies is around 41% and it might seem relatively enough. In terms of basic technology, while its share is the lowest (around 25%), it has the highest source of uncertainties among technology types. In this case, the proposed model helped to have a clear and precise improvement plan towards prioritizing technology and knowledge focus.
Go to article

Abstract

The application of artificial intelligence (AI) in modeling of various machining processes has been the topic of immense interest among the researchers since several years. In this direction, the principle of fuzzy logic, a paradigm of AI technique, is effectively being utilized to predict various performance measures (responses) and control the parametric settings of those machining processes. This paper presents the application of fuzzy logic to model two non-traditional machining (NTM) processes, i.e. electrical discharge machining (EDM) and electrochemical machining (ECM) processes, while identifying the relationships present between the process parameters and the measured responses. Moreover, the interaction plots which are developed based on the past experimental observations depict the effects of changing values of different process parameters on the measured responses. The predicted response values derived from the developed models are observed to be in close agreement with those as investigated during the past experimental runs. The interaction plots also play significant roles in identifying the optimal parametric combinations so as to achieve the desired responses for the considered NTM processes.
Go to article

Abstract

This paper is a case study conducted to present an approach to the process of designing new products using virtual prototyping. During the first stage of research a digital geometric model of the vehicle was created. Secondly it underwent a series of tests utilising the multibody system method in order to determine the forces and displacements in selected construction nodes of the vehicle during its movement on an uneven surface. In consequence the most dangerous case of loads was identified. The obtained results were used to conduct detailed strength testing of the bicycle frame and changes its geometry. For the purposes of this case study two FEA software environments (Inventor and SolidWorks) were used. It has been confirmed that using method allows to implement the process of creating a new product more effectively as well as to assess the influence of the conditions of its usage more efficiently. It was stated that using of different software environments increases the complexity of the technical process of production preparation but at the same time increases the certainty of prototype testing. The presented example of simulation calculations made for the bicycle can be considered as a useful method for calculating other prototypes with high complexity of construction due to its systematized character of chosen conditions and testing procedure. It allows to verify the correctness of construction, functionality and perform many analyses, which can contribute to the elimination of possible errors as early as at the construction stage.
Go to article

Abstract

One of the key factors of a competitive economy is creating a strong, internationally competitive SME sector. This essay is based on the fact that management tools used in the SME sector are insufficient. With the development of these tools, the competitiveness of companies could improve. According to the literature, using lean thinking has a positive influence on the company’s effectiveness, and also proved that lean approach can be successfully extended out of the car industry, into the limitedly resourced SME sector, too. Even though the topic of lean manufacturing is analysed by many studies, there is a lack of papers dealing with its usage in the SME sector. The originality of this paper lies in analysing the current status of using lean manufacturing practices among the Hungarian SMEs operating in the manufacturing industry. The paper includes an examination about how deeply the elements of lean thinking are present in the Hungarian SME sector, how large the development reserves are, and whether there is a difference between the usage of lean practices. A structured questionnaire was used for data collection. SMEs’ representatives, mostly CEOs and managers from the Hungarian manufacturing industry participated in the survey. The sample contained 128 observations. The study has two control variables, which are the size of the company and the relation to the lean management. The survey brought the following results. First of all, it shows that the level of using lean is low among the Hungarian SMEs. Furthermore, customer orientation is a key factor in the sector, however, there are considerable possibilities for progress by the inner processes and the handling and involvement of the suppliers. Firstly, a good basis to increase the effectiveness could be the creation of thinking in processes influencing the supply chain. Secondly, the development of the leadership and the involvement of the employees at some level are also significant. Key findings is that without state incitement and the involvement of outside experts, progress cannot be expected to spread on a broad scope. The background of the research method was created to fit the available literature and to capable to be used in other countries, too. Moreover, this way the available information can be expanded with a regional dimension, in case further studies are going to be made.
Go to article

This page uses 'cookies'. Learn more