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The Analysis of Hospital Helicopter Landing Sites Location in Terms of their Vibroacoustic Impact

Abstract

According to the applicable regulations, in the case of a decision on the location of an investment consisting in the construction and commissioning of a helicopter landing field, it is necessary to carry out an environmental impact assessment. At the same time, due to the emission of noise related to the expected change of acoustic climate parameters, the indicators required under the applicable law related to building acoustics and also impact of vibration on the structure of buildings should be taken into account. The article discusses particular groups of issues related to the assessment of the impact of helicopter landing field on the environment and the hospital building. On the basis of the presented results of analyzes, a postulate concerning the necessity of introducing a comprehensive assessment methodology, including specific groups of issues, was formulated.

Open access
A Concept of Suborbital Scientific Mission and Technology Validation

Abstract

Suborbital platforms are one of alternatives for satellites. They offer cheaper access to space to perform broad range of scientific and technology R&D. One of suborbital platforms are sounding rockets, which are suitable for these applications. A concept of scientific mission utilizing the sounding rocket is presented by author in this paper. The novelty of this mission is the operational responsive launch approach, which presents the example of the mission which responds for payload user needs, not payload contest approach, which is often in scientific community competing for payload space in space agency sounding rocket launch campaigns. The main mission goal is to perform astronomical observation of NEO using IR/VIS telescope. The secondary goal is to qualify the instrument for use on astronomical satellite observatory and raise its technology readiness level from TRL 6 to TRL 8. The expected mission output is to gain scientific data on NEO object and perform new IR/VIS optoelectronic instrument technology validation.

Open access
Conformity of finished forming sieves for paper industry

Abstract

The sieves’ manufacturers that want to be competitive at the market must have the implemented quality control system. Different methods, based on taking the sample, which is a representative of the total quantity of the forming sieves production, are applied for evaluation of the sieve’s conformity. The basic characteristics of this type of the quality function are control, measuring and testing of the forming sieves’ properties at the end of the manufacturing process. The objective is to detect and separate the products that deviate from the set criteria, to remain in the factory, then to be repaired if possible or discarded in the opposite case and thus to prevent delivery of the defective sieves to the paper manufacturers.

Open access
Determination of In-Plane Shear Properties of Laminate with V-Notch Rail Shear Test and Digital Image Correlation

Abstract

This article presents the results of the application of Digital Image Correlation (DIC) to measurements of in-plane shear modulus and strength of three different carbon fiber reinforced laminates. Three different approaches to shear strain calculations via DIC are evaluated and compared with standard strain gage measurements. Calculation of shear strain based on averaging DIC strain values of strain gages area in most cases yielded results closest to strain gages, while measurements based on single point strain measuring differed the most from strain gages. These results are attributed to shear strain distribution in the center area of the specimen. Thermoplastic matrix fabric reinforced composite had the lowest shear strength at 5% of shear strain, but the highest ultimate shear strength and strain at failure. Of thermosetting materials, laminate reinforced with unidirectional carbon fiber had shear modulus about 10% lower, than fabric reinforced laminate, but higher ultimate strength and strain at failure. This behavior is attributed to the presence of weaves in fabric reinforcing the laminate, causing shear stiffening of the material, but lowering its ability to deform under shear loading.

Open access
The effect of changing injection temperature on some mechanical and morphological properties for polypropylene material (PP)

Abstract

This is a study of a medical injection factory-Babylon carried out in order to achieve proper mechanical and morphological properties, PP has been injection molded by using cold runner injection molding machine with temperature variation (198, 200, 203……220°C) for ten samples. The physical and mechanical properties of PP product were examined. It has been found that the Shore hardness decreases linearly with injection molding temperature increasing. The tensile strength has a similar behavior to the hardness. However, it has been found that the MIF (Melt Index Flow) rates increases with the increase of injection molding temperature. The density of PP has been found for both virgin PP and the samples, it has been found that the density decreases with increasing operation temperature. FTIR (Fourier Transmission Infrared) spectra were taken for both samples with high and low operation temperature. Besides the SEM (Scanning Electronic Microscopy) test shows the difference in the morphology of the product surface and the PP product at high and low operation temperature. Moreover, for all these properties, the PP product exhibits good mechanical properties (hardness, tensile strength, density) for the samples produced at temperature lower than 207°C. While the physical properties such as MIF improved with injection temperature increasing, additionally, the SEM images show that the sample produced in low temperature have surface damage.

Open access
An effective selection process is the key to quality job positions occupation conditional for long-term competitiveness

Abstract

The need for adaptation to rapid changes in the business environment, both on the part of employees and employers, implies dealing with new challenges, acquisition of new knowledge and skills and assumption of new roles and responsibilities. The base for companies is the availability of qualified human resources, which is ensured by the human resource management department mainly through an effective process of employee selection. The paper is oriented at the analysis of the current state of focus of organizations operating in Slovakia on systematicity and complexity of the selection process, the existence of an effective internal labor market and the regularity of development of used selection tools in the context of technological progress and changes in labor market requirements in regions of Slovakia. Results of the survey on (n = 343) enterprises show a positive trend, an increase of more than 10 percent in the orientation towards improvement of the process of employee selection, but on the other side it also confirm an increase in disparities between individual regions of Slovakia, some regions (Eastern Slovakia) progress much slower than the developed ones (Bratislava).

Open access
Elimination of constraints in the production process of power equipment components and the analysis of the resulting benefits

Abstract

The article presents the results regarding the elimination of constraints in the production process of a power equipment subassembly, a boiler chamber, together with an analysis of the benefits resulting from this, both financial and non-financial. The significance of bottlenecks in the production process, ways of its identification and limitations - in general - are presented. The article is a case-study of an attempt to eliminate the bottleneck in the production process of the boiler chamber, which turned out to be the process of drilling and marking-off, and work stations representing these processes. In order to eliminate the limitation, it was decided to replace the existing tracing and drilling work with a numerically controlled device - a boring machine moved from the liquidated department.. As a result, labor-intensive, manual chambers marking-off and the process of drilling holes with a smaller diameter drill have been eliminated. A number of benefits has been demonstrated resulting from the elimination of the bottleneck in the process, first of all, it was possible to reduce the duration of the marking-off and drilling operations and reduce the costs of the boiler chamber production process.

Open access
Improving Quality Management - the Way Toward Economic Prosperity and Quality of Life

Abstract

The National Quality Programme of the Slovak Republic for 2017-2021 strongly emphasises the primary objectives and priorities of the Quality Improvement Strategy. This should be one of the main priorities of the Slovak Government in the upcoming period. The Quality Improvement Strategy should, in general, lead to an improvement in the quality of life. The aim of the paper is to point out the opportunities for improvement by applying indicators aimed at defining the excellence of organisations within the national economy of the Slovak Republic.

Open access
The influence of a goal programming approach for safety management practices on the performance of a selected Indian construction organization

Abstract

The construction industry in India is the second most important contributor to its gross domestic product. However, high rate of accidents and fatalities have tarnished the image of industry in India. Although the industry contributes significantly to the Indian economy, safety management is the primary concern alongside with frequent workplace accidents. The role of safety management is vital to improve safety performance of an organization. The functions of safety management include planning, organizing, staffing, directing, controlling and coordinating safety activities with an aim to minimize accidents/injuries. Safety trainings, employee participation, compliance of safety procedures and motivational schemes are part of safety management which influences the overall safety performance. Several metrics were developed to measure the safety performance of an organization but not a single measure will reflect the overall performance. The present study considered parameters pertaining to the safety management which have influence on the safety performance of a construction organization in India. The parameters are analyzed by formulating a goal programming model. The results of the study suggests that much improvement is needed in the area of safety trainings and the revised targets were established.

Open access
Influence of Honeycomb Core Stabilization on Composite Sandwich Structure Geometry

Abstract

Authors showed the influence of stabilization of the honeycomb core on shape of the composite sandwich test panel. Adhesive film laid on core ramps and cured with suitable cure cycle served as core stabilizer. Test panel geometry included different ramp angles (20° and 30°). To verify stabilization process a technology trial was performed. Three test panels were manufactured (3-stage, 1-stage and 1-stage with stabilized core). All test panels were manufactured in OoA process (Out of Autoclave). Panel surfaces were scanned with 3D scanner and compared with the reference CAD model. Both outer skin and inner skin were manufactured in Automated Fiber Placement Laboratory of Warsaw Institute of Aviation.

Open access