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Behaviour Based Safety (BBS) - Advantages and Criticism

Abstract

Behaviour-Based Safety (BBS) is a popular approach to enhancing occupational safety, with many researchers reporting successes of implementing BBS programs. There are, however, studies that see this approach as illusory, bringing more harm than good. The first goal of this article is to present an overview of literature providing both evidence and elaboration of implementing BBS programs, highlighting both positive and negative views of the approach. The second goal is to discuss the perception of the method, based on a literature review and authors’ own research.

Open access
Bionics in Aviation

Abstract

In the paper bionics as a field of knowledge and inspiration in the aviation technologies is presented. Bionics is a branch of science on the borderline of art and biology that studies the way living organisms work, as well as their structure, in order to use the results to build technical devices. In the introduction part definition of bionics is described. In the next part of this document the aviation technologies inspired by nature is depicted. Then, technologies inspired by the butterfly wing are presented. The paper ends with conclusions.

Open access
Bonding of High Temperature Thermoplastic Carbon Composites with Resistance Welding Technique

Abstract

The article presents ‘state-of-the art’ on joining fibre reinforced thermoplastic composites with the use of resistance welding technique. Their welding process and potential difficulties connected with the process and quality control of a manufactured element are presented. The structure of a typical thermoplastic composite welding stand was also presented. The main welding technology elements were characterized: structure of the resistance element, implementation of the thermal process and pressure application required for joining materials. The paper also presents the required calibration ranges for a technological process with the use of strength test types SLS, DCB, SBS and nondestructive testing of joint with the ultrasonic method.

Open access
Comparative Analysis of the Level of Satisfaction with the Services Received at the Business Incubators in USA and Poland – pre-incubation and incubation stage

Abstract

The paper concentrate on the problems of customers satisfaction from services in incubator centres in USA and Poland. The aim of the paper is to analyse the level of satisfaction of Business Incubation Centre on the example of two incubator centres one from USA (Hazelton CAN-Be in Pennsylvania and second in Gliwice Poland). The analysis was conducted in pre-incubation and incubation stage. The analysis was conducted on example of survey analysis in both incubator centres. On the base of achieved results we assessed the priority of customers in each incubator centre.

Open access
Flight Tests of Turboprop Engine with Reverse Air Intake System

Abstract

This work presents selected results of I-31T propulsion flight tests, obtained in the framework of ESPOSA (Efficient Systems and Propulsion for Small Aircraft) project. I-31T test platform was equipped with TP100, a 180 kW turboprop engine. Engine installation design include reverse flow inlet and separator, controlled from the cockpit, that limited ingestion of solid particulates during ground operations. The flight tests verified proper air feed to the engine with the separator turned on and off. The carried out investigation of the intake system excluded possibility of hazardous engine operation, such as compressor stall, surge or flameout and potential airflow disturbance causing damaging vibration of the engine body. Finally, we present evaluation of total power losses associated with engine integration with the airframe.

Open access
Food quality and safety in the brewing industry

Abstract

The article presents the importance of economic and social responsibility of the brewing industry, pointing to the aspect of synergy related to the brewing industry in the processes of economic development (creation of many jobs in the agricultural sector, retail trade and gastronomy), stimulating specific areas of local and regional development. The principles of organization and supervision of food quality and safety in beer brewing as well as the importance of implementing management systems in the activity of brewing industry companies were presented.

Open access
Irregular operation of autonomous vehicles

Abstract

Today, with the spread of autonomous functions in vehicles, the role accountability for causing accidents is emphasized. Self-guided functions work in certain traffic situations, but accidents happen, and, therefore, the following article presents an analysis of the issue. Its purpose is to show that vehicles with self-drive functionality do not provide the driver's level of safety that vehicle manufacturers suggest. In this article, four recent events and an analysis whether these accidents could have been avoided a human driver or how they could have happened with appropriate self-drive function. In each of the investigated cases, vehicles equipped with self-drive function are involved. Based on the evaluation and assessment of accidents, conclusions are drawn whether current self-propelled vehicles provide the safety level that drivers and society expect from these vehicles. The reconstruction of the accident process is illustrated with the help of a vehicle simulation program, with the resultant parameters being given a special emphasis, in particular to the avoidance of the accident.

Open access
The outline of the expert system for the design of experiment

Abstract

The design of experiment (DoE) is a methodology originated from early 1920s when Fisher’s papers created the analysis of variance and first known experimental designs: latin squares. It is focused on a construction of empirical models based on measurements obtained from specifically structured and driven experiments. Its development resulted in the constitution of four distinctive branches recognized by the industry: factorials (full or fractional), Taguchi’s robust design, Shainin’s Red-X®and a response surface methodology (RSM). On one hand, the well-known success stories of this methodology implementations promise great benefits, while on other hand, the mathematical complexity of mathematical and statistical assumptions very often lead to improper use and wrong inferences. The possible solution to avoid such mistakes is the expert system supporting the design of experiments and subsequently the analysis of obtained data. The authors propose the outline of such system and provides the general analysis of the ontology and related inference rules.

Open access
Preliminary Design Analysis of Regenerative Cooling for N2O/Alcohol Small Scale Liquid Rocket Engine

Abstract

This paper presents a concept of a small scale liquid-propellant rocket engine designed in AGH Space Systems for sounding rocket. During preliminary design of thermal aspects various ways of cooling were evaluated and described. Possible issues and design approaches for ablative, radiation and regenerative cooling are raised. The authors describe available solutions. Regenerative cooling is especially concerned as it is most popular solution in bi-liquid engines, in which alcohol fuel acts as coolant and is preheated before it reaches combustion chamber. To estimate a possible temperature distribution - and thus an applicability of such a system in the engine - a mathematical model of heat transfer was developed. Unique element of said engine is its oxidizer - nitrous oxide, which have been rarely used to date. Comparison between typical LOX bi-liquids is given and major differences that affect cooling arrangement are discussed. The authors compared different combinations of coolants, fuel/oxidizer ratios etc. to optimize the temperature distribution which is a key factor for the engine performance.

Open access
The Research of Acoustic Emission of a Low-Power Aircraft Engine

Abstract

This paper presents the methodology and investigation of the sound power level produced by a radial piston aircraft engine operating at varied speeds. The research model aircraft engine of a maximum power of 5.5 kW with a two-bladed airscrew was placed on a test bend. Its sound power level was calculated from the sound pressure level measured at 9 measurement points distributed on a hemispherical surface in a confined space in line with PN-EN 3744. Mean sound power generated by the ASP FS400AR engine is 96 dB at idle (2,880 rpm) and 105 dB at a cruising speed (4,740 rpm). Accordingly, it can be concluded that a sound level meter registered a higher sound power level at the points in front of the model aircraft engine than at the points behind it, whereas the lowest sound power level was registered directly above the engine.

Open access