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Waste Management Integration with Green Quality Function Deployment (G-QFD) for Healthcare Centre

Abstract

High doses of medical waste evidence that health waste management is problematic. A case study was conducted at various health institutions. This research analyzes various issues in the area of medical waste management. The research examines the perception of staff regarding medical waste management. The purpose of the study is to investigate the level of knowledge, attitudes and role of health practitioners in the management of medical waste.

Here the quality index and the environmental index of two health centers are studied; one is a private hospital and the other one a state hospital and compares these two indices with a questionnaire.

To provide environmentally friendly services, customers and environmental criteria have to be taken into account in the decision-making process and distributing the Green Quality Function provides a very useful way to achieve this goal.

Open access
Analysis of Systems Ensuring the Acquisition of Real-Time Cartographic Navigation Information

Abstract

Electronic Chart Display and Information Systems (ECDIS), which are used on vessels and can replace paper charts, allow to obtain and display on electronic charts information from basic and additional data sources. For the certified use of ECDIS instead of paper charts, it is necessary to ensure constant updating of Electronic Navigation Chart (ENC) data provided to vessels for use. The known visual and satellite observation systems intended for cartographic information update are costly, have low accuracy and do not allow to quickly update navigational charts in real-time mode. The stand-alone use of remotely piloted aircraft (RPA) will make it possible not only to substantially reduce costs and increase the accuracy of monitoring, but also to provide information in real-time mode.

Open access
Bending of an annular three-layer circular plate

Abstract

The main objective of this work is the numerical analysis of the strength and stiffness of an annular three-layer circular plate with variable mechanical properties of the core. The plates are subjected to bending. Numerical analysis of the deflection phenomenon is carried out under different support conditions of the plate. Furthermore, the influence of the material properties of the core (linear and non-linear model) on the shear stresses and deflecions is also investigated.

Open access
Development of a computational model of a lightweight vertical lathe with the use of superelements

Abstract

This article presents a process of developing a computational model of a light construction vertical lathe. The model is made using the finite elements method. Due to the complexity of the machine tool and the optimization of the computation time superelements have been used in the model. The application of this method has reduced the computation time allowing the analysis of many variants of the mutual position of the machine components. The results of the analyzes led to the indication of weak links of the machine tool. After the improvement of the machine tool construction the movement of the tool tip and the workpiece was much smaller.

Open access
Influence of heat treatment on the structure and properties of polyamide 6/ halloysite nanocomposites

Abstract

The nanocomposites of polyamide 6 (PA6) with halloysite nanotubes (HNT) were prepared by extrusion using co-rotating twin-screw extruder and then the standard test specimens were injected using a screw injection moulding machine. The content of HNT in the nanocomposites was 5 or 10 weight percent. The heat treatment of unmodified PA6 and nanocomposites was carried out in silicone oil in temp. 150±2°C. The samples were annealed for 3 hours and then cooled at a rate of 4 K/min. Differential scanning calorimetry (DSC) causes annealing to increase the crystallinity of the polyamide matrix. After an annealing treatment a nanocomposite with better mechanical properties was obtained. Halloysite nanotubes in polyamide matrix play the role of a nucleating agent.

Open access
Kinematic model of multiple trailers on a tractor system for production logistics applications

Abstract

This paper demonstrates kinematic analysis of multiple trailers on a tractor system for production logistics. The analysis concerned three different steering systems of the trailers: virtual clutch and drawbar system, conventional clutch and drawbar system, double Ackermann steering system. Designed kinematic models contain various variants of paths: turning at a constant value of the steering angle, changing the steering angle as a result of an approaching collision. Each of these variants also included driving in a straight line after a 90° turn. The validation of the developed kinematic model was done by using a real logistic train, which path was registered via aerial drone. For each of the developed kinematic models, a visualization of drive through the 90° turn was created.

Open access
Measurement strategy as a determinant of the measurement uncertainty of an optical scanner

Abstract

The subject of the article is an attempt to determine the impact of the applied measurement strategy on the accuracy of the measurement result. This problem is particularly crucial when measuring large objects. In these cases, it is not always possible to provide ideal conditions for the submission of particular scans. It is necessary to adjust the strategy to specific imposed conditions defined by the geometry of the object and to the time frame of the measurement itself.

With regard to the above, an attempt was made to carry out a series of accuracy studies testing the structural light scanner while measuring elements of overall dimensions greater than the measuring capacity of the scanner. At the same time, various potential measuring strategies were simulated in practical applications. Our studies were conducted using a pre-designed test template with a defined distribution pattern of reference points and geometrical elements. Moreover, in order to make an in-depth investigation of the issue, some trials were undertaken with the use of limiting parameters. That means the scanner had both an excess and shortage of information required for a correct assembly of scans. Those scopes were taken into consideration in the study in order to use the acquired knowledge in practical measuring applications. Furthermore, conclusions from the conducted studies indicate peaks and troughs of respective measuring strategies with special care for determining relationships among the used strategies and the measuring accuracy parameters.

Open access
Risk Assessment of the Adverse Events in Air Transportation

Abstract

In the field of security in transport distinguish risks related to flight safety and aviation security. Safety of flights is ensured through the reliability of aviation equipment and the qualification of the personnel who services and operates it, aviation security is a condition of protection from illegal interference in its activity. Risk management in civil aviation in the field of security is a relatively new direction of activity. Deep research in this area began only at the beginning of the XXI century. It is quite difficult to use the existing experience of risk management, accumulated in other spheres, as civil aviation has significant features. Various methods and schemes can be used to assess risks. The article discusses various options for predicting risks using the “event tree” and “risk factor tree” methods.

Open access
RPAS Satellite Communication Channel Based on IEEE 802.11b Standard

Abstract

Original models of RPAS communication channels based on IEEE 802.11b Standard, including both Base Station transmission within the Radio Line of Sight, and through the satellite using Beyond Radio Line of Sight, were built. Dependencies of the Bit Error Rate on the Signal-Noise Ratio for different payload data rates were obtained. Transponder nonlinearity and Base Station antenna diameter impact were analysed.

Open access
Ship Noise Level Analysis Based on the International Regulations

Abstract

The target of analyse was to determine the exposure levels to the staff on the vessel and ensure adequate measures are in place to minimize the exposure when necessary. Noise levels through the vessel will be compared to the noise code detailed in section 2 of this report. The measurement data results obtained at this survey will be analysed against the codes, as shown below. In addition, the measurement result table has the readings from 2007 during sea trials at the shipyard, Brodogradilište d.o.o. – Split. The analyse is to measure the exposure levels, through the accommodation and machinery spaces to determine the risk to staff working in these areas as well as making recommendations that could reduce the exposure levels.

Open access