Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 5
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

The article presents an analysis of the real role of the complementarity principle and the reasons why immi-gration law is still based on this principle. The basic assumptions of the state’s attitude towards labour im-migration were set out in a period when this kind of immigration to Poland was at a much smaller scale than currently. First and foremost, one of the basic premises is the complementarity of labour immigration (com-plementarity principle) with the labour market test as an element of the procedures, although with some exceptions. The mechanism of controlling the complementarity is obligatory and preventive. The current economic situation in Poland, including the conditions for the functioning of immigration law, is very differ-ent from the reality of that time. In view of growing shortages of Polish employees on the labour market one can doubt whether preventive enforcement of complementarity by law is needed. The complementarity of labour immigration to Poland is a socio-economic fact and legal guarantees to ensure this result seem ob-solete. There are strong arguments to consider that opportunistic political motivations are the main reason against the rationalisation of legal regulations concerning immigration of workers. The complementarity principle has become a facade of restrictive immigration law, while allowing for its use in a way that ensures the access of immigrants to the labour market.

Go to article

Authors and Affiliations

Paweł Dąbrowski
ORCID: ORCID
Download PDF Download RIS Download Bibtex

Abstract

Wood plastic composite (WPC) is a lightweight material, resistant against corrosion and damage, with recyclability of consuming materials. These materials usually used in marine structures frequently due to their unique features. In order to strengthen beams made by this material, usually Fibre-reinforced plastic (FRP) sheets are used, and one of the fracture modes in these beams is debonding of FRP sheet from the surface of the beams. To deal with this problem some grooves are used in the surface of the beam to improve the contact surface. The grooves include longitudinal, transverse and diagonal grooves. The main goal of this study is to assess different grooving methods in WPC-FRP beams. In this regard, primarily criteria (improving resistance, performance speed, performance complexity, performance costs, displacement and absorbing energy) were determined through interviews with experts in this field in order to assess the beams. Then, SWARA method employed to evaluate criteria with a policy based perspective and finally EDAS method applied for evaluating related alternatives. Based on obtained results, the longitudinal groove method is the best way of strengthening WPC beams to prevent debonding.

Go to article

Authors and Affiliations

Mahdi Chini
Shahid Arefi Lale
Sarfaraz Zolfani Hashemkhani
Leonas Ustinovicius
Download PDF Download RIS Download Bibtex

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.

Go to article

Authors and Affiliations

C. Sivakumar
R. Malathy
P. Sivaprakash
Download PDF Download RIS Download Bibtex

Abstract

Several conclusions and recommendations concerning sediment trap geometry, the technique of their deployment and interpretation of measurements results are described in this paper. Only cylindrical sediment traps are able to cope with the diverse and dynamic environment of glaciated fjords. The relation between different trap parameters shows the optimal proportion of cylinder diameter as being between 6 and 10 cm and ratio length/diameter not less than 7/1. During the peak of the melting season in Kongsfjorden (Spitsbergen) the rate of sedimentation of total matter reaches over 900 g m–2 d–1 and the velocity of brackish water current can reach 80 cm s–1 on the surface. Owing to the high productivity of Arctic fiords and large concentration of suspended mineral matter it is possible to collect of large samples in a short time, therefore prevention of sediment traps by swimmers is not necessary.

Go to article

Authors and Affiliations

Marek Zajączkowski
Download PDF Download RIS Download Bibtex

Abstract

The experiment leads to establish the influence of radiated surface development heat exchangers on the values of heat flux transferred with water flowing through the exchangers and placed in electric furnace chamber. The values of emissivity coefficients are given for the investigated metal and ceramic coatings. Analytical calculations have been made for the effect of the heating medium (flame) – uncoated wall and then heating medium (flame) – coated wall reciprocal emissivity coefficients. Analysis of the values of exchanged heat flux were also realized. Based on the measurement results for the base coating properties, these most suitable for spraying the walls of furnaces and heat exchangers were selected, and determined by the intensification of heat exchange effect. These coatings were used to spray the walls of a laboratory waste-heat boiler, and then measurements of fluxes of heat absorbed by the cooling water flowing through the boiler tubes covered with different type coatings were made. Laboratory tests and calculations were also confirmed by the results of full-scale operation on the metallurgical equipment.
Go to article

Authors and Affiliations

Sławomir Morel

This page uses 'cookies'. Learn more