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Number of results: 110
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Abstract

The main reason behind the development of the International Safety Management Code was a series of tragic maritime accidents at the end of the twentieth century caused by human error. The ISM Code has introduced a brand new instrument, the safety management system (SMS), to the set of already existing legal devices, established to ensure safety during ship operation. Properly applied and implemented within the shipping company, SMS can be an advantage that will not only result in a measurable increase in the level of safety, but will also result in cost optimization and an increase in the company’s reputation. However, if an SMS is conceived without commitment and conviction on the part of the management, it will be only an empty and façade, bureaucratic procedure that will not only fail its purpose, but will also only be an additional burden for all staff. The following article will present the characteristics of SMS and its impact both on the broadly understood safety in the shipping company, and including vessels in its fleet, moreover the requirement of the efficiency of SMS procedures specified in shipboard manual for each vessel will be emphasized, which is the need to create a new safety culture.

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Authors and Affiliations

Michał Małczyński
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Abstract

Work in unfavorable, changing environmental conditions negatively affects people working on scaffoldings used on construction sites, which may increase the risk of occurrence of dangerous situations. The purpose of this article is to show the scale of temperature changes which workers are exposed to. The paper compares examples of temperature measurements obtained from a metrological station and during tests on scaffoldings located in the Lodz and Warsaw regions. This article also presents the methodology of examining environmental parameters of the surroundings where employees work on scaffoldings. Analysis results show that high temperatures and significant temperature variations frequently occur on the scaffoldings, which leads to a lack of adaptability and consequently to tiredness or decreased alertness. Unfavorable environmental conditions can lead to behaviors which, in turn, can cause accidents.

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Authors and Affiliations

I. Szer
E. Błazik-Borowa
J. Szer
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Abstract

The paper presents the problem of intelligent installations in buildings, their construction and integration with other systems present in the building. Attention has been focused on systems designed to ensure the safety of property and persons residing in different facilities. It also discusses ways to control the microclimate and other aspects of the building so as to obtain the maximum comfort of the people placed in them. Considering its high popularity, the smart installation based on the KNX/EIB standard is further discussed, examples of algorithms for dealing with security threats are given as well as the functions indicated which can improve the comfort of using a facility.
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Authors and Affiliations

Jacek Majcher
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Abstract

U-turn lanes eliminate left turns at intersections and allow the manoeuvre to be made via median crossovers beyond the intersection. However, there are many situations where road infrastructures are characterized by the reduced width of the median. It is clear that, in such situations, we must adopt design criteria that take into account limitations imposed by the width of the cross-section of the road. This is the reason why it is necessary to adopt design solutions which expect a complete reorganization of the road section affected by the insertion of U-turns. In this paper, we intend to propose original guidelines for U-turn lane design, suitable to guarantee both the necessity to offer a high level of functionality of the road sections to be implemented by U-turns, and the principles of safety in order to reduce unsafe conditions during inversion manoeuvres as much as possible.

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Authors and Affiliations

N. Distefano
S. Leonardi
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Abstract

The paper presents findings from research project Mobis which is aimed at developing a method of assessing safety of unsignalised pedestrian road crossings using video image analysis. Pedestrian and vehicle traffic has been recorded at selected zebra crossing sites in Warsaw and Wrocław, before and after installation of active signage systems SignFlash and Levelite. Speeds of approaching vehicles were measured and drivers’ behaviour was classified using video analysis.

The paper presents a comparison of effectiveness of systems such as SignFlash and Levelite based on changes in the mean and standard deviation of vehicle spot speeds as well as changes in speed profiles of vehicles approaching the crossings.

Results indicate that both SignFlash and Levelite active signage reduce mean vehicle approach speeds and have a positive impact on drivers’ behaviour.

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Authors and Affiliations

P. Olszewski
W. Czajewski
P. Dąbkowski
C. Kraśkiewicz
P. Szagała
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Abstract

To reliably calibrate suitable partial safety factors, useful for the specification of global condition describing structural safety level in considered design case, usually the evaluation of adequate failure probability is necessary. In accidental fire situation, not only probability of the collapse of load-bearing structure, but also another probability related to the people staying in a building at the moment of fire occurence should be assessed. Those values are different one from another in qualitative sense but they are coupled because they are determined by similar factors. The first one is the conditional probability with the condition that fire has already occured, whereas the second is the probability of failure in case of a potential fire, which can take place in the examined building compartment, but its ignition has not yet appeared. An engineering approach to estimate such both probabilities is presented and widely discussed in the article.

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Authors and Affiliations

M. Maślak
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Abstract

In the paper methods for conducting Road Safety Inspections (SIs) in Italy and Poland are described and compared. The goal of the study is to improve the quality and efficiency of the safety inspections of road network by using low cost equipment (GPS, Tablet, Camera) and specific software. Particular attention was paid to the need for proper calibration of factors, causing traffic safety hazard associated with road infrastructure. The model developed according to the Italian procedures was adapted to comply with the checklists and evaluation criteria of the Polish guidelines. Overall, a good agreement between the two approaches was identified, however some modification was required to include new safety issues, characteristic for the Polish network for safety inspection of two lane rural roads. To test the applicability about 100 km of regional two lane roads in Poland were inspected with Polish and Italian procedures.

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Authors and Affiliations

S. Cafiso
M. Kieć
M. Milazzo
G. Pappalardo
F. Trovato
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Abstract

The article presents the issue related with a proper preparation of a data sheet for the

analysis, the way of verifying the correctness and reliability of input information, and proper

data encoding. Improper input or coding of data can significantly influence the correctness

of performed analyses or extend their time. This stage of an analysis is presented by an

authorship questionnaire for the study on occupational safety culture in a manufacturing

plant, using the Statistica software for analyses. There were used real data, obtained during

the research on the issue of occupational safety and factors having the greatest influence on

the state of occupational safety.

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Authors and Affiliations

Patryk Krupa
Izabela Gabryelewicz
Milan Edl
Peter Pantya
Justyna Patalas-Maliszewska
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Abstract

The construction industry in India is the country’s second largest industrial sector, after agriculture. The construction industry makes a remarkable contribution to the Indian economy and provides employment to a large number of people of Idia. Fire is a chemical reaction of a combustible substance with oxygen, involving heat and is usually accompanied by a visual flame or incandescence. Ensuring fire safety has always been a challenge to the stakeholders, i.e. building owners, construction companies, contractors and sub-contractors, and government employees due to the multiplicity of the factors involved and their complexity. There are various legal standards and requirements for ensuring fire safety on construction sites. The buildings are normally provided with firewalls during construction and these firewalls separate two structures or divide a structure into smaller portions to prevent the spread of fire. The lightweight construction and trusses are designed to support only their own weight. During a fire, if one fails, a domino effect happens and all fail rapidly within 5 to 10 minutes. Prolonged exposure to fire may result in structural collapse and injury or death of the occupants of the building under construction. Fire safety on construction sites is still in its primitive stages in India. There is a great necessity to improve fire safety on construction sites to protect construction workers and other occupants of the buildings. This study aims to design and implement fire safety systems for construction sites, thereby enhancing the standards to meet the system requirements at par with global standards.

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Authors and Affiliations

C. Sivakumar
R. Malathy
P. Sivaprakash
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Abstract

The article discusses the dangers arising from construction disasters. This phenomenon is the most serious effect of the risk that may occur in construction. I presented this on the basis of an analysis of all construction disasters that have taken place in Poland in the last twenty years. I made a detailed analysis of the events that occurred during the maintenance of building facilities, taking into account the reasons for their occurrence and the effects they cause. The aim of this analysis is to identify areas of risk in order to eliminate the hazard and, as a consequence, take appropriate actions to counteract this type of events. Unfortunately, one should be aware that despite technical progress building disasters cannot be completely avoided in our surrounding, but one must use the knowledge acquired on this basis to minimize their number.

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Authors and Affiliations

J. Szer
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Abstract

This paper describes a design process of HALE PW-114 sensor-craft, developed for high altitude (20 km) long endurance (40 h) surveillance missions. Designed as a blended wing (BW) configuration, to be made of metal and composite materials. Wing control surfaces provide longitudinal balance. Fin in the rear fuselage section together with wingtips provide directional stability. Airplane is equipped with retractable landing gear with controlled front leg that allows operations from conventional airfields. According to the initial requirements it is twin engine configuration, typical payload consists of electro-optical/infra-red FLIR, big SAR (synthetic aperture radar) and SATCOM antenna required for the longest range. Tailless architecture was based on both Horten and Northrop design experience. Global Hawk was considered as a reference point – it was assumed that BW design has to possess efficiency, relative payload and other characteristics at least the same or even better than that of Global Hawk. FLIR, SAR and SATCOM containers were optimised for best visibility. All payload systems are put into separate modular containers of easy access and quickly to exchange, so this architecture can be consider as a „modular”. An optimisation process started immediately when the so-called “zero configuration”, called PW-111 was ready. It was designed in the canard configuration. A canard was abandoned in HALE PW-113. Instead, new, larger outer wing was designed with smaller taper ratio. New configuration analysis revealed satisfactory longitudinal stability. Calculations suggested better lateral qualities for negative dihedral. These modifications, leading to aerodynamic improvement, gave HALE PW-114 as a result. The design process was an interdisciplinary approach, and included a selection of thick laminar wing section, aerodynamic optimisation of swept wing, stability analysis, weight balance, structural and flutter analysis, many on-board redundant systems, reliability and maintability analysis, safety improvement, cost and performance optimisation. Presented paper focuses mainly on aerodynamics, wing design, longitudinal control and safety issues. This activity is supported by European Union within V FR, in the area Aeronautics and Space.

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Authors and Affiliations

Z. Goraj
A. Frydrychewicz
R. Świtkiewicz
B. Hernik
J. Gadomski
T. Goetzendorf-Grabowski
M. Figat
St. Suchodolski
W. Chajec
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Abstract

Starting from consideration that urban intersections are sites with promise for safety and operational improvements, the paper describes the steps taken to develop a crash predictive model for estimating the safety performance of urban unsignalized intersections located in Palermo, Italy. The focus is on unsignalized four-legged one-way intersections widespread in Italian downtowns. The sample considered in the study consist of 92 intersections in Palermo, Italy. For the study were collected crashes occurred in the sites during the years 2006‒2012, geometric design and functional characteristics and traffic flow. Results showed that data were overdispersed and NB1 distributed. In order to account for the correlation within responses Generalized Estimating Equations (GEE) were used under different working correlation matrices.

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Authors and Affiliations

O. Giuffrè
A. Granà
T. Giuffrè
R. Marino
S. Marino
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Abstract

The paper focuses on different approaches to the safety assessment of concrete structures designed using nonlinear analysis. The method based on the concept of partial factors recommended by Eurocodes, and methods proposed by M. Holicky, and by the author of this paper are presented, discussed and illustrated on a numerical example. Global safety analysis by M. Holicky needs estimation of the resistance coefficient of variation from the mean and characteristic values of resistance, and requires two separate nonlinear analyses. The reliability index value and the sensitivity factor for resistance should be also identified. In the method proposed in this paper, the resistance coefficient of variation necessary to calculate the characteristic value of resistance may be adopted from test results and the resultant partial factor for materials properties, and may be calculated according to Eurocodes. Thus, only one nonlinear analysis from mean values of reinforcing steel and concrete is required.

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Authors and Affiliations

Sz. Woliński
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Abstract

The article discusses the relationship between energy quality technologies cutting and their environmental friendliness. Based on the energy analysis shows that energy consumption in the individual technological process is connected with the cutting power and power loss, which form the environmental indicators of the cutting process and reduce its energy efficiency. In addition, it is shown that at implementation of technological processes on the equipment, electrical systems are AC systems the implementation of the cutting process occurs when excessive consumption of currents. The article presents the results of studies on the energy efficiency of cutting processes, definition of the complex influence of cutting processes on the environment and humans, the formation of ways of improving environmental and energy performance quality of these processes.

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Authors and Affiliations

Tadeusz Zaborowski
Leonid Shvartsburg
Natalja Ivanova
Sergej Ryabov
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Abstract

The problem of poor quality of traffic accident data assembled in national databases has been addressed in European project InDeV. Vulnerable road users (pedestrians, cyclists, motorcyclists and moped riders) are especially affected by underreporting of accidents and misreporting of injury severity. Analyses of data from the European CARE database shows differences between countries in accident number trends as well as in fatality and injury rates which are difficult to explain. A survey of InDeV project partners from 7 EU countries helped to identify differences in their countries in accident and injury definitions as well as in reporting and data checking procedures. Measures to improve the quality of accident data are proposed such as including pedestrian falls in accident statistics, precisely defining minimum injury and combining police accident records with hospital data.

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Authors and Affiliations

P. Olszewski
B. Osińska
P. Szagała
P. Skoczyński
A. Zielińska
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Abstract

The meaning and scope of the concept of security in extenso, as well as its special type, i.e. maritime safety and security, has been the subject of many considerations and discussions for decades, and perhaps for centuries. Security is most often understood as one of the basic functions of the State implying counteracting all threats. In axiological terms, as a risk-free state, maritime safety is a value, and in functional terms, as a desirable state, it is expressed in the protective function of law. The law must be structured in such a way as to constantly realize this function. Achieving maritime safety can therefore be seen as the capacity of law and institutions, for example, to protect a ship against loss, protect health and life of people employed on a ship, and protect the environment from pollution.

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Authors and Affiliations

Dorota Pyć
ORCID: ORCID
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Abstract

In the event of occupational accidents in mining, investors can calculate approximately how much loss will be incurred at the time of the accident. However, in halting mining as a result of occupational accidents or legislation, investors, will perhaps not care about how much of a loss to profits will arise due to the resulting downtime of mining operations. The reason for this is that there is no such halting in mining operation as yet and mining activity is continued. Avoiding halting mines due to occupational accidents and legislation would enable the prevention of unexpected costs resulting from these time losses. The aim of this study was to find out how much the loss of profits resulting from the downtime of mining enterprises due to the aforementioned reasons are in total, and how much the ratio of loss of profits to annual operating costs is on average on an annual basis. To determine the loss of profits and to minimize the accidents in enterprises, permanent supervisors, who are assigned in the enterprises where they are working, were given a survey through the SurveyMonkey program. Of the 235 permanent supervisors who filled out the survey on behalf of the mining enterprises, 58 answered all of the multiple-choice questions examined in the study. These questions were analyzed together according to different mineral groups and differences in mining operation methods. As a result of the analysis, it was determined that the annual loss of profits of mining enterprises resulting from the aforementioned periods of downtime, and the ratio of these values to the annual operating costs constitute a rather significant share. The aim of the article was to raise awareness to have mining companies appropriate more funds for occupational health and safety.
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Authors and Affiliations

Taşkın Deniz Yıldız
1
ORCID: ORCID

  1. Adana Alparslan Türkeş Science And Technology University, Department of Mining Engineering, Turkey
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Abstract

Is the burning of woody biomass climate friendly?
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Authors and Affiliations

Rafał Chudy
1
Kacper Szulecki
2
ORCID: ORCID
Jacek Siry
3
Robert Grala

  1. FOROS/FBA/Forest Monitor, Norway
  2. Department of Political Science, University of Oslo, Center for Energy Research, Norwegian Institute of International Affairs
  3. Warnell School of Forestry and Natural Resources, University of Georgia, United States
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Abstract

This paper provides an analysis of the evacuation process in a road tunnel in the event of a fire, using the example of the tunnel under the Luboń Mały mountain currently being constructed on Expressway S7’s Lubień – Rabka-Zdrój section. As fires are the largest and most dangerous events occurring in road tunnels, it is important to predict the evacuation process as early as at the design stage. The study described here used numerical modelling to simulate evacuation, which made it possible to determine the required safe evacuation time of all tunnel users in a fire. On the basis of the parameters of the tunnel under Luboń Mały, numerical studies were performed for four different fire scenarios, three of which assumed various fire locations with the currently designed two traffic lanes. The fourth variant accounted for the planned extension of the roadway to include three traffic lanes. Eventually, four numerical models were developed involving various fire ignition locations and numbers of potential tunnel users. The values of initial-boundary conditions used in the simulation, such as movement speed during evacuation, shoulder breadth and pre-movement time, were specified on the basis of experimental data for an evacuation performed in smoke conditions in the Emilia tunnel in Laliki. The results lead to the conclusion that if the time of reaching critical conditions in the tunnel is not shorter than 5 minutes 40 seconds for the current design state and 5 minutes 47 seconds for three lanes, the distribution of evacuation exits in the tunnel under Luboń Mały will ensure safe evacuation.
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Bibliography

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[2] A . Voeltzel, A. Dix, A comparative analysis of the Mont Blanc, Tauern and Gotthard tunnel fires. World Road Association (PIARC ) 324, 18-34 (2004).
[3] I . Maevski, Design Fires in Road Tunnels, A synthesis of Highway Practice. New York: Transportation Research Board NCHR P National Cooperative Highway Research Program Synthesis 415. (2011).
[4] British Standard. The application of fire safety engineering principles to fire safety design of buildings. Human factors. Life safety strategies. Occupant evacuation, behaviour and condition, BSI. PD 7974-6:2004.
[5] E . Ronchi, P. Colonna, J. Capote, D. Alvear, N. Berloco, A. Cuesta, The evaluation of different evacuation models for assessing road tunnel safety analyses. Tunnelling and Underground Space Technology 30, 74-84 (2012). doi: 10.1016/j.tust.2012.02.008
[6] E . Ronchi, M. Kinsey, Evacuation models of the future: insights from an online survey of user’s experiences and needs. Advanced Research Workshop – Evacuation and Human Behaviour in Emergency Situations 145-155 (2011).
[7] N. Schmidt-Polończyk. Ocena możliwości stosowania wentylacji wzdłużnej w długich tunelach drogowych. Assessment of the possibility to apply longitudinal ventilation in long road tunnels. PhD thesis, AGH UST (2016).
[8] Road Tunnels: Operational Strategies for Emergency Ventilation. France: PIARC Committee on Road Tunnels (2011).
[9] M . Kinateder, P. Pauli, M. Müller, J. Krieger, F. Heimbecher, I. Rönnau, Human behaviour in severe tunnel accidents: Effects of information and behavioural training. Transportation Research Part F: Traffic Psychology and Behaviour 17, 20-32 (2013). doi: 10.1016/j.trf.2012.09.001
[10] E . Ronchi, K. Fridolf, H. Frantzich, D. Nilsson, A.L. Walter, H. Modig, A tunnel evacuation experiment on movement speed and exit choice in smoke. Fire Safety Journal 97, 126-136 (2018). doi: 10.1016/j.firesaf.2017.06.002
[11] M . Seike, N. Kawabata, M. Hasegawa, Evacuation speed in full-scale darkened tunnel filled with smoke. Fire Safety Journal 91, 901-907, (2017). doi: 10.1016/j.firesaf.2017.04.034
[12] C. Casse, S. Caroly, Analysis of critical incidents in tunnels to improve learning from experience. Safety Science 116, 222-230 (2019), DOI : 10.17632/scrdwnzc7t.1
[13] K . Fridolf, E. Ronchi, D. Nilsson, H. Frantzich, The representation of evacuation movement in smoke-filled underground transportation systems. Tunnelling and Underground Space Technology 90, 28-41 (2019), doi: 10.1016/j. tust.2019.04.016
[14] J. Porzycki, N. Schmidt-Polończyk, J. Wąs, Pedestrian behavior during evacuation from road tunnel in smoke condition – Empirical results. PLOS ONE 13 (8), e0201732 (2019). doi: 10.1371/journal.pone.0201732
[15] I. Donald, D. Canter, Intentionality and fatality during the King’s Cross underground fire. European Journal of Social Psychology 22 (3), 203-218 (1992).
[16] K . Fridolf, D. Nilsson, H. Frantzich, Fire Evacuation in Underground Transportation Systems: A Review of Accidents and Empirical Research. Fire Technology 49 (2), 451-475 (2013). doi: 10.1007/s10694-011-0217-x
[17] Thunderhead Engineering. Pathfinder 2014.2 Verification and Validation (2014).
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[19] P. Liszka, Ocena bezpieczeństwa ewakuacji w tunelu pod Luboniem Małym. Master’s Thesis, AGH University of Science and Technology (2018).
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[21] M . Moussaïd, N. Perozo, S. Garnier, D. Helbing, G. Theraulaz, The Walking Behaviour of Pedestrian Social Groups and Its Impact on Crowd Dynamics. PLOS ONE. 5 (4), 1-7 (2010). doi: 10.1371/journal.pone.0010047
[22] RABT : Forschungsgesellschaft fur Strassen-and Verkehrswesen, Richtlinien fuer Ausstattung und Betrieb von Strassentunneln (2006).

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Authors and Affiliations

Natalia Schmidt-Polończyk
1
ORCID: ORCID
Zbigniew Burtan
1
ORCID: ORCID
Piotr Liszka
1

  1. AGH University of Science and Technology, Al. A. Mickiewicza 30, 30-059 Krakow, Poland
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Abstract

The article analyzes factors that may have an impact on Occupational Safety in a construction company and the issues of work safety in construction were discussed. An attempt was made to analyze the management of work safety in construction companies in order to identify important factors and determine the significance of their participation in the occurrence of accidents at work. The research was carried out on the basis of data obtained from the register kept at the District Labor Inspectorate in Krakow. Cases which were discussed included accident protocols prepared pursuant to the law, as well as cases found in protocols of ad hoc inspections carried out on construction sites. There were quantitative and qualitative features in the analyzed data set. Logistic regression was used to analyze the data to build the model. Such action made it possible to model and determine the significance of the influence of individual variables characterizing the way of managing work safety in construction companies, in the case of an accident. The results obtained, and in particular the significance of factors shown in the model, even not directly related to the construction site, may be an indication for creating a functional strategy in the enterprise. The strategy assuming: smaller number of accidents or adverse events, shorter downtime will build a reputation of an institution that cares for the employee. This will allow the construction company to become more competitive and shall attract the best professionals available on the labor market. The end result is the identification of key factors that have a direct impact on work safety and the competitiveness of a construction company.
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Authors and Affiliations

Marcin Kowalik
1
ORCID: ORCID
Wojciech Drozd
1
ORCID: ORCID

  1. Cracow University of Technology, Faculty of Civil Engineering, Division of Management in Civil Engineering, ul. Warszawska 24, 31-155 Kraków, Poland
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Abstract

Due to different reasons a significant modal shift from railway to road transport took place over last decades. The basic reasons are pointed in the paper introduction together with contradicting transport policy taking into account environmental and economical challenges. Political vision to stimulate modal shift from road and air to railway cannot become true without achieving railway technical and operational interoperability. Paper describes wide range of technical barriers between individual intraoperable railway systems in civil engineering structures, traction power supply, control command and signalling and the ways, which are being applied to ensure stepwise converging of the technical solutions taking into account safety and technical compatibility, as well as other essential requirements, namely: reliability, accessibility, health and environment.

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Authors and Affiliations

M. Pawlik
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Abstract

The paper looks at the issues of operation safety of the national power grid and the characteristics

of the national power grid in the areas of transmission and distribution. The issues of

operation safety of the national transmission and distribution grid were discussed as well as threats

to operation safety and security of the electricity supply related to these grids. Failures in the

transmission and distribution grid in 2017, caused by extreme weather conditions such as: a violent

storm at the night of 11/12.08.2017, hurricane Ksawery on 5–8.10.2017, and hurricane Grzegorz on

29–30.10.2017, the effects of which affected tens of thousands of electricity consumers and led to

significant interruptions in the supply of electricity were presented. At present, the national power

(transmission and distribution) grid does not pose a threat to the operation safety and security of

the electricity supply, and is adapted to the current typical conditions of electricity demand and the

performance of tasks during a normal state of affairs, but locally may pose threats, especially in

extreme weather conditions. A potentially high threat to the operation safety of the national power

grid is closely linked to: age, technical condition and the degree of depletion of the transmission and

distribution grids, and their high failure rate due to weather anomalies. Therefore, it is necessary

to develop and modernize the 400 and 220 kV transmission grids, cross-border interconnections,

and the 110 kV distribution grid (especially in the area of large urban agglomerations), and the MV

distribution grid (especially in rural areas). The challenges faced by the transmission and distribution

grid operators within the scope of investment and operating activities, with a view to avoiding

or at least reducing the scale of grid failures in the case of future sudden high-intensity atmospheric

phenomena, are presented.

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Authors and Affiliations

Waldemar Dołęga
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Abstract

The article presents the results of tests on SHC-40 hydraulic props equipped with two types of valve blocks: standard (with spring steel cylinder) and BZG-2FS (with gas spring). The research was conducted using impact mass of 4,000 kg and with extreme dynamic load of free fall impact mass of 20,000 kg released from different heights h. The dynamic tests involved a camera with the speed of image capture up to 1,200 frames/sec, which made it possible to register the stream of liquid at the dynamic load and to determine the valve opening time. The study conducted on SHC-40 NHR10 props equipped with two types of valve blocks: a standard and the BZG-2FS fast acting relief, showed that the prop with the BZG-2FS block is more suitable and more effective in the case of areas with high risk of mining tremors and rapid stress relief of a seam. Research methodology developed in the Central Mining Institute combines digital recording technique of pressure in a prop and fast registration of the images, and allows to acquire more accurate analysis of dynamic phenomena in the prop during testing.
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Authors and Affiliations

Andrzej Pytlik
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Abstract

Toys emitting sounds are classified as significant sources of noise found in the children environment. Impulse and continuous noise emitted by toys, used in close to the child’s ear, acting directly on the organ of hearing, can lead to serious adverse health effects. This is especially true for children under the age of three, in which the state of the hearing organ determines their intellectual development. The current level of safety of sound emitting toys intended for children in this age group is insufficient. This is confirmed by the reports from the control of market surveillance authorities. A new approach to the assessment of children’s exposure to noise generated by toys, included in EN 71-1:2011 + A2:2013 Standard, based on the permissible values applicable to the workplaces, requires further tests and verification. The paper presents the results of the research work and assesses the level of sound emitted by toys in the light of current standard requirements, carried out using the author’s methodology. Toys intended for children under the age of 3 years, commercialized on the European market by Polish manufacturers and importers were tested. The results of the tests allowed us to determine the impact of duration of the sound pressure level measurement on the final result.
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Authors and Affiliations

Beata Grynkiewicz-Bylina
Bożena Rakwic

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