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A. Ambroziak, M. T. Solarczyk and A. Biegus

Abstract

This paper focuses on an analytical and numerical investigation of aluminium brackets used to fasten light-weight curtain walls to building facilities. The authors propose a solution to increase the load capacity of aluminium brackets by means of additional cover plates (straps). This paper also includes a short survey of literature and material properties concerning the EN AW-6060 T6 aluminium alloy. This paper suggests an initiation of a comprehensive investigation on aluminium brackets.

Open access

M. Kwietniewski, D. Miedzińska and T. Niezgoda

Abstract

The problem of effective gas extraction from Polish shale rocks is an interesting research subject for scientists. A properly selected proppant, which protects cracks from closing during the fracturing process, inestimably contributes to an increase of extraction. Grains of proppant are transported along with a fracturing medium to reach the deepest regions of the crack. The proper support of the crack provides an easy flow of gas, therefore it is important in terms of extraction efficiency. This paper shows the interactions of a proppant grain with the crack surface in shale rock. FEM analysis was conducted to observe the stress region, which is generated as a result of pressing the grain into the crack surface. A model of a sphere which was pressed into the rock model with constant velocity was applied. The received results of stress depend on material properties and a range of proppant grain pressing.

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L. Jiao and X.D. Li

Abstract

With the development of the society in recent years, there are more and more housing construction areas. The traditional concrete has not been able to satisfy the demand of housing construction. In this study, prefabricated concrete was applied in the design of assembling style houses considering their characteristics, and its economic, environmental and social benefits were analyzed combining risk matrix evaluation method and management strategy. It was found that the use of prefabricated concrete as a building material could effectively shorten the construction period, reduce the construction cost and improve the construction safety, playing a role of energy saving and environmental protection. Therefore it was concluded that prefabricated concrete can improve the efficiency of construction, reduce environmental pollution and save energy. This work provides a reference for the application of prefabricated concrete in residential buildings and its safety management.

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N. Ibadov

Abstract

The new approach to the construction project planning is presented in the article. The classical net model is enriched by the fuzzy decision node. The decision node allows for alternate choices dependent on appearing circumstances. The alternative net model with fuzzy decision node is an acyclic multi-graph, where some, chosen nodes (events) have multiple connections. These connections represent alternative methods of the certain work execution. Every work (activity) (i, j) in the net model with alternative methods of work execution, despite the basic information comprising the execution time, the cost, the number of necessary workers, should comprise additional information e.g. about a complexity of works, a real feasibility. The alternative ways of a given work execution are evaluated in the decision node based on the fuzzy decision model. Each method is evaluated by assigning it the preference level in a form of the value of the membership function - „equal or higher” μ≥ . The most preferable way of the work execution in a given circumstances, will have the highest value of preference level. When the choice is done the net model is solved in the traditional way. Therefore, the paper concentrates on the process of choosing the method of work execution in the fuzzy decision node. The example calculations accompanying the process of decision taking are presented too. The model requires the use of linguistic variables, a fuzzy numbers, as well as fuzzy preference relations together with some calculations applied the probability theory.

Open access

Rafał Miętkiewicz

Abstract

In order to first Baltic LNG terminal in Świnoujście construction, issues concerning maritime critical infrastructure protection as a part of Maritime Security appeared. With the increasing natural gas demand LNG terminal in Świnoujście could be a possible terrorist attack target as well as the LNG carriers crossing the choke point of Baltic Straits and sailing through the littoral waters of Polish and other Baltic counties coastline. Experts do not fully agree on possible effects and results of successful terrorist assault on LNG carrier at sea nor at harbor.

Unmanned platforms begin to play prominent role in military, oceanography or academic applications. With the announcement of reducing the hazard for deck operators especially in high-risk regions, it is predicted that unmanned platforms will play crucial role in Maritime Security systems in the nearest future. This paper discusses the design of the USV dedicated to LNG terminal protection tasks introduces potential equipment options and missions scenarios of first Polish unmanned platform ‘Edredon’.

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Piotr Szymak and Michał Przybylski

Abstract

In the recent years, a dynamical development of an underwater robotics has been noticed. One of the newest group of underwater robots are biomimetic underwater vehicles. These vehicles are driven by undulating propulsion imitating fins of underwater creatures, e.g. a fish, a seal, etc.

This paper undertakes problem of thrust measurement of new biomimetic underwater vehicle equipped with undulating propulsion. At the beginning, the stand for thrust measurement is described. Then, two constructions of BUVs imitating a fish and a seal are presented. Further, the results of thrust measurement for two different undulating propulsions are inserted. At the end of the paper containing conclusions from performed measurements and foreseen research is included.

Open access

P. Sivaprakash and S. Kanchana

Abstract

There are about 8.5 million workers employed in the construction sector in India. Construction workers constitute a major portion of the unorganized labour and are characterized by their casual nature of employment, temporary relationship with the employer, prolonged and uncertain working hours, lack of safety and health measures, and inadequacy of basic amenities and welfare facilities. There are many legislation clauses providing safeguards for contract workers in India. Construction safety has been made legally enforceable after the enactment of The Building and Other Construction Workers (Regulation of Employment and Conditions of Service) Act in 1996 and the Central Rules in 1998. This paper details various statutory provisions for construction safety in India with specific reference to the BOCW Act, Central Rules, and State Rules.

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Krzysztof Just and Paweł Piskur

Abstract

In this paper a results of a static analysis of the tubular linear electromagnetic actuator is presented. The linear actuator consist of two parts: a cylindrical unmovable coils surrounded by a soft ferromagnetic case, and a runner made from sequence of permanent magnet with a soft ferro-magnetic gasket. In the first part of the paper the analytical method was performed for preliminary analysis. In the second part of the paper the more detailed analysis was depicted with using finite element method (FEM). The magnetic circuit shape and impact of selected dimensions on static characteristics is presented. Then the axial and radial electromagnetic force as a function of the runner dimensions were analysed.

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Ryszard Kłos

Abstract

This article is one of the series dedicated to the DiveSMART Baltic project conducted to better coordination of international underwater rescue operations in the Baltic Sea. The project DiveSMART Baltic has received Flagship status.

The article is the forth in the planned cycle of articles referring tasks realised in the Naval Academy in the framework of DiveSMART Baltic project. This article describes selected decompression procedures for victims who became saturated by air at maximum depth to H =30 mH 2 O in the air pockets of the hull of a sunken wreck. This subject is associated with the work package four ‘Medical treatment’ of the DiveSMART Baltic project: Identifies methods for different medical treatments in operational areas.

Open access

Iulian Dinulescu and Cristian Troncotă

Abstract

Human behavior has generated a series of threats to human security throughout history, generating major violence at the time when it was doubled by an exaggerated religiosity. Religious fanaticism has manifested itself in all societies, regardless of their forms of organization. The consequences of the phenomenon deeply marked inter-human relationships, both within the community, but especially in communities that have other religions. The article shows the characteristics of religious fanaticism and the factors that cause people to adopt such a behavior of exacerbating religious zeal doubled into intolerance towards those of opponents, both of other faiths and those within their own confession.

The issue is not generated by the religious phenomenon or religiosity that such sectarians or religious organizations and religious fanaticism have with some of the members of such religious entities. They are transformed into perfect soldiers because they respond to clergy ‘requests, even with the sacrifice of their own lives, without counting for these individuals, the feelings for their own family members or the duty to support them. In such situations the phenomenon mentioned can not be prevented until it is truly understood from the religious point of view. Therefore, particular attention must be paid to the motivations that lead some individuals to such behavior, as well as to the characteristics of such religious fanatics, and to the way they create risks to human security. In this article we will only address the religious fanaticism manifested by Christianity and Islam, because these are the ones that can have an impact at European and national level. To this end, we will look at some elements of religious fanaticism that indicate this kind of behavioral pattern. After that we will clarify and show the reader the connection between religious fanaticism, the behavior of the followers influenced by this phenomenon, and the inter-human relationships determined by this type of actors.