Wyniki wyszukiwania - Biblioteka Nauki

1

Difficulties observed in operating powered roof support during work in lower range of its working height

100%

Płonka M. , Rajwa S.

Mining – Informatics, Automation and Electrical Engineering

|

2018

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tom R. 56, nr 4

45--54

EN

Significant maintenance difficulties have recently been observed in terms of the proper maintenance of mining roofs during the operation of powered roof supports in their low section height range, which is characterized by a wide working range. These difficulties were also encountered in situations where the calculated load capacity index of the roof “g” reached favorable values. These phenomena occurred most often during extraction under gobs and when maintaining a protective roof carbon shelf of the required thickness. This paper presents the calculations and analyses aimed at clarifying and discussing these events.

2

Research on Forming Parameters Optimization of Incremental Sheet Forming Process for Commercially Pure Titanium Grade 2 Sheets

88%

Szpunar M. , Trzepieciński T. , Ostrowski R. , Zwolak M.

Archives of Metallurgy and Materials

|

2022

|

tom Vol. 67, iss. 4

1411--1418

EN

This study aims to determine optimal forming parameters for Incremental Sheet Forming process Commercially Pure titanium Grade 2 sheets in terms of formability improvement, force reduction, and efficiency of forming. Based on the central composite design, data were collected during 20 runs and then variation analysis was performed. The experiments were performed on a 3 axis CNC milling machine equipped with a Kistler dynamometer plate. Subsequently, regression models have been developed to describe process responses by input factors. As crucial parameters, the relative velocity and step size of the tool that affect the forming force and the height of the fracture have been determined. Finally, the application of optimization algorithm has emerged optimal input factors in terms of selected multi-criteria goal. The results of this study suggest that there is a process window that allows the formation of 45° wall angle drawpieces of commercially pure titanium Grade 2.

3

Kaliningrad oblast in the military system of the Russian Federation

88%

Żyła M.

Security and Defence Quarterly

|

2019

|

tom 25

|

nr 3

99-117

EN

From the geopolitical point of view, the Kaliningrad Oblast, due to its exclave location, has become an area of strategic importance. Its strategic nature has been steadily increasing with the successive enlargements of the European Union and NATO. The geographical location and the army stationed in the area allow Moscow to control the situation in the Baltic Sea basin. This makes it possible, through the Euro-Atlantic location of most countries in the region, to influence European policies. In this way, Russia is playing a leading role in this part of the continent. From the point of view of the countries within the region, it is a global military power and a regional superpower. In this context, Kaliningrad exclave increasingly more frequently serves as a security policy tool. It is part of the ongoing threat to the Baltic States and Poland. Demilitarisation of the region, which is periodically demanded by neighbouring countries, is impossible for several reasons. The armed forces stationed there are a counterbalance to the expanding North Atlantic Treaty Organisation from Russia’s point of view. They serve to protect national interests and secure the affairs of the Russian and Russian-speaking diasporas in the immediate vicinity. They protect the Russian economic zone and access to the resources of the Baltic Sea. Moreover, the military potential located in the Kaliningrad Oblast, since the collapse of the Soviet Union, has been a guarantee of continuity of Potsdam’s border solutions.

4

Hybrid warfare challenges

75%

Vuković J. , Matika D. , Barić S.

Security and Defence Quarterly

|

2016

|

tom 12

|

nr 3

118-138

EN

In this article, hybrid warfare challenges and their impact on the evolution of warfare in the new dynamic security environment are analysed. The aim of the research was to identify hybrid threats, explore the complexity of the hybrid conflict that involves professional Armed Forces and irregular (paramilitary) forces. The research has been conducted through two case studies of hybrid warfare: the Israeli - Lebanese conflict in 2006 and the Lebanese militia organisation Hezbollah as a prototype of hybrid opponents; and the contemporary hybrid conflict in Ukraine through the Russian paradigm of hybrid warfare. The conducted research showed that the decisive role that influenced the outcome of the conflict belonged either to rapidness or inertia in of the making of political decisions. The research results showed further that revision of the existing strategic and doctrinal documents are required, as well as reorganisation of the national security system (and the Armed Forces as part of it), without which they will not be able to deal successfully with the dynamic nature of future conflict and complexity of threats (“synergy of threats”). The political decision is the most essential parameter for sizing military organisation. The rapidity of response in the event of emergencies (especially outside the national territory) also depends on the promptness of political decisions in order to activate the Armed Forces.

5

The ontology of destiny and freedom among the Igbo-African: a discourse in existential metaphysics

75%

Ukwamedua N. U. , Omokpo V.

IDEA. Studia nad strukturą i rozwojem pojęć filozoficznych

|

2016

|

tom 28/2

272-286

EN

From an existential and metaphysical standpoint, the African world is dualised into the physical and metaphysical world. This is bald-faced in the dynamics of the relationship that characterizes the African worldview. In praxis, the metaphysical world is seen to be higher in the scheme of things because, it is from it that the impersonal beings/forces operate and superintend on the physical world of man. It is based on this that the twin issue of destiny and freedom is topical and recurrent in Igbo-African metaphysics. The concern is whether man can be free in the physical world, which seems to be a manifestation of the will/wishes and/or the whims and caprices of the beings/forces in the metaphysical world. It is consequent upon this that this paper undertook an existential analysis of these contending issues of freedom and destiny within the Igbo-African context. From the analysis, it was palpable that, though there can be manipulations from the metaphysical world which can bring about luck (good or ill), the Igbo-African is expected to make effort to excel and work responsibly with his chi; because, a man can have a good or bad luck but his/her practical effort is still expedient.

6

Interaction of Non-Metallic Inclusion Particles with Advancing Solidification Front

75%

Kalisz D.

Archives of Metallurgy and Materials

|

2014

|

tom Vol. 59, iss. 2

493--500

EN

This work deals the phenomenon interaction of crystallization front on the particles of non-metallic precipitates. The behavior of a single particle in the vicinity of horizontal and vertical front was analyzed. The forces acting on the particle were characterized and the equilibrium condition formulated, from which the critical velocity of front may be deduced. The calculation results were illustrated in the form of graphs.

PL

Praca zajmuje się zjawiskiem oddziały wania przemieszczającego frontu krystalizacji na cząstki wydzieleń niemetalicznych. Analizowano zachowanie pojedynczej cząstki wydzielenia w pobliżu poziomego i pionowego frontu. Scharakteryzowano siły działające na cząstkę w pobliżu frontu i sformułowano warunek równowagi, z którego wynika szybkość krytyczna frontu. Wyniki obliczeń zilustrowano w postaci wykresów.

7

The Russian Federation Dominance in the International Security Environment

75%

Banasik M.

Polish Political Science Yearbook

|

2022

|

nr 3 (51)

7-17

EN

This article presents the research results, which set out to explain the mechanisms leading to the achievement of dominance by the Russian Federation in the international security environment. In the research process, the systemic approach was applied. Analysis and criticism of the literature, non-participatory observation and case study elements were used to solve the research problems. As a result, it was determined that the theoretical basis for the Russian Federation's achievement of international dominance is the concept of new generation war. The model of the strategic influence of the Russian Federation is directed at the shaping of the security environment and includes the synchronisation of kinetic and non-kinetic measures, indirect and direct effects, the blurring of the boundaries between war and peace and the application of pressure and aggression. The Russian Federation achieves strategic dominance through asymmetry, chaos, reflexive control, and strategic deterrence. Armed forces provide a key role in asserting dominance, focused on conducting offensive activities and inflicting losses with conventional and nuclear weapons.

8

The Role of Think Tanks in Actions for Defence Diplomacy. An Example of Poland

75%

Olszyk S.

Polish Political Science Yearbook

|

2022

|

nr 3 (51)

155-181

EN

With the end of the 20th century, there was a change in the nature and methods of using military force in international politics. It led to the need to develop new cooperation methods between states and reorient military diplomacy into defence diplomacy. In the new reality, the group of entities influencing diplomatic activities has been expanded to include non-governmental entities, including think tanks. It raised questions about the role of expert centres in activities for defence diplomacy under Polish conditions, including shaping the international situation and shaping the state's defence policy. The following considerations are an attempt to answer this question. The analysis was based on the data obtained from a survey and information from the websites of fifteen Polish centres of expertise operating in international relations, political science, and security and defence.

9

Znaczenie pomiaru sił napinających w linach odciągowych masztu dla jego bezpiecznej eksploatacji

63%

Artymiuk J. , Bednarz S.

Wiertnictwo, Nafta, Gaz

|

2009

|

tom T. 26, z. 1--2

63-68

PL

Maszt wiertniczy będący lekką stalową konstrukcją przewoźną zwykle teleskopową przeznaczony jest do wykonywania prac wyciągowych. Maszt w pozycji pracy posiada parostopniowe nachylenie w stronę otworu wiertniczego. Maszt stabilizowany jest przez liny kotwiące, które są częścią konstrukcji układu nośnego. W czasie eksploatacji przenoszą część obciążeń roboczych, dlatego przestrzeganie zalecanych wartości sił napinających liny odciągowe spełnia ważną rolę w zapewnieniu bezpieczeństwa eksploatacji masztu. Układ lin odciągowych, napięcia w linach, nośności kotew, są przedstawione w dokumentacji techniczno ruchowej danej wiertnicy oraz w odpowiednich normach. Przeprowadzone próby obciążeniowe masztów uwidaczniają wpływ sił napinających liny odciągowe na przemieszczenie układu przestrzennej kratownicy konstrukcji nośnej.

EN

Drilling mast as a light steel mobile design commonly telescoped is provided for hoisting operations. Mast is deviated at few degrees in front to hole centerline at work position. Guy wire ropes stabilize mast and are part of its design They are loaded from part of hook load during drilling operation and meeting to recommendation relative to tension forces values of guy wire ropes is very important in safety assurance. Drilling rig operation manual and proper standards include guy wire rope arrangement, tension forces and anchor capacities. Impact of tension forces in guy wire ropes on mast framework displacement has made visible by mast load tests carried out.

10

The influence of cooling techniques on cutting forces and surface roughness during cryogenic machining of titanium alloys

63%

Wstawska I. , Ślimak K.

Archives of Mechanical Technology and Materials

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2016

|

tom Vol. 36

12--17

EN

Titanium alloys are one of the materials extensively used in the aerospace industry due to its excellent properties of high specific strength and corrosion resistance. On the other hand, they also present problems wherein titanium alloys are extremely difficult materials to machine. In addition, the cost associated with titanium machining is also high due to lower cutting velocities and shorter tool life. The main objective of this work is a comparison of different cooling techniques during cryogenic machining of titanium alloys. The analysis revealed that applied cooling technique has a significant influence on cutting force and surface roughness (Ra parameter) values. Furthermore, in all cases observed a positive influence of cryogenic machining on selected aspects after turning and milling of titanium alloys. This work can be also the starting point to the further research, related to the analysis of cutting forces and surface roughness during cryogenic machining of titanium alloys.

11

Friction stir processing – State of the art

63%

Węglowski M. S.

Archives of Civil and Mechanical Engineering

|

2018

|

tom Vol. 18, no. 1

114--129

EN

Increasing demands for operating properties of fabricated elements on one hand, and a necessity of reducing mass of a structure on the other, triggers materials engineering research into producing surface layers representing required functional properties. Methods commonly used in the production of surface layers, such as surfacing, spraying or re-melting with a laser beam have been known for years. A new method is the friction stir processing (FSP) of surface layers. The FSP process is primarily used for the modification of microstructure in near-surface layers of processed metallic components. In particular, the process may produce: fine grained structure, surface composite, microstructural modification of cast alloys, alloying with specific elements, improvement of welded joints quality. The chapter is composed of a few main parts. In the first part, based on literature review the main application and achievements of FSP processes are presented. In the second part: analysis of the process. The third part is focused on microstructure refinement and the last part provide information about friction stir alloying as well as friction stir processing with ultrasonic vibration.

12

Wysokość strefy nieustalonego ruchu cząstek w pionowym transporcie pneumatycznym

63%

Raczek J. , Dzido G. , Palica M.

Inżynieria Chemiczna i Procesowa

|

2001

|

tom T. 22, z. 3E

1207--1212

PL

W oparciu o bilans sil działających na cząstki w strumieniu gazu zaproponowano zależność na obliczanie wysokości strefy nieustalonego ruchu cząstek.

EN

Equation for estimation of the height of the unstable particles move zone has been proposed using the balance of forces acting on particles in gas of stream.

13

Analiza sił oraz drgań podczas frezowania kompozytu metalowo-ceramicznego

63%

Znojkiewicz N. , Madajewski M. , Twardowski P. , Wojciechowski S.

Mechanik

|

2018

|

tom R. 91, nr 8-9

763--765

PL

Przeanalizowano składowe siły całkowitej oraz drgań podczas frezowania kompozytu metalowo-ceramicznego F3S.10S firmy Duralcan™ frezami, których ostrza są wykonane z dwóch materiałów: PCD oraz CBN. Badanie przeprowadzono przy zmiennych parametrach frezowania, tzn. różnych prędkościach skrawania vc i posuwu fz. Pomiary drgań i sił wykonywano w trzech kierunkach: posuwowym (Ff, Af), posuwowym normalnym (FfN, AfN) oraz odporowym (Fp, Ap). Z otrzymanych przebiegów sił i drgań wyznaczono miary punktowe, takie jak wartości średniokwadratowe. Analizy przeprowadzono zarówno w funkcji czasu, jak i częstotliwości. Analiza w głównej mierze dotyczyła wpływu prędkości skrawania i posuwu na poziom amplitud drgań i sił. Dodatkowo przeprowadzono analizę częstotliwościową.

EN

Presented is the analysis of the cutting forces and vibrations during milling of the F3S.10S Duralcan™ metal-ceramic composite, using milling cutters made of two materials: PCD and CBN. The test was carried out with variable milling parameters, i.e. cutting speeds vc and feed fz. Measurements of vibrations and forces were made in three directions: feed (Ff, Af), feed normal (FfN, AfN), and resistant (Fp, Ap). The root mean square values were determined from the received forces and vibrations. The analysis was made both as a function of time and frequency. The analysis mainly concerned the impact of the cutting speed and the feed on the level of the amplitudes of the vibrations and forces. An additional frequency analysis was carried out.

14

A study characterizing dynamic overloads of professional dancers. Biomechanical approach

63%

Dworak L. B. , Gorwa J. , Kmiecik K. , Mączyński J.

Acta of Bioengineering and Biomechanics

|

2005

|

tom Vol. 7, nr 1

77-84

EN

Many jumps made in classical and modem ballet are responsible for serious injuries. A pilot experiment that was earned out with two professional dancers measured the temporary character of ground reaction forces in a few chosen elements of classical dance. The method of piezoelectric dynamometry as well as video recording were applied. The results of the experiment concerning the dynamic overloads, which are defined by the value of ground reaction forces, allow us to set the direction of a further research in the area of biomechanical interpretations.

15

Experimental and simulation research of forces and stresses acting on the hoe coulter

63%

Selech J. , Ulbrich D. , Włodarczyk K. , Kowalczyk J. , Kęska W. , Spiczak-Brzeziński P.

Journal of Research and Applications in Agricultural Engineering

|

2016

|

tom Vol. 61, nr 2

92--96

EN

The main aim of the experiment was to determine in the laboratory conditions forces acting on the hoe coulter. The measurements were carried out on an abrasive test unit type "rotating bowl" unit using designed and built measuring system. The velocity of the coulter was in the range of 1,11 to 2,22 m·s-1, and the depth of penetration into the river sand was 40 or 60 mm. On the basis of the designated forces a computer simulation of stresses and displacements of the coulter tip was carried out. The obtained results made it possible to know the relation between aggravating forces, velocity and depth of immersion of the coulter in the soil, which can be used to calculate wear rates or the coulter levers strength.

PL

Głównym celem przeprowadzonego eksperymentu było wyznaczenie w warunkach laboratoryjnych sił działających na redlicę, która przemieszczała się z prędkościami liniowymi w zakresie od 1,11 do 2,22 m·s-1, a jej zagłębienie w piasku rzecznym wynosiło 40 lub 60 mm. Pomiary przeprowadzono na stanowisku, do badań elementów maszyn pracujących gruncie, typu „wirująca misa” z wykorzystaniem zaprojektowanego i zbudowanego układu pomiarowego. Na podstawie wyznaczonych sił przeprowadzono symulację komputerową naprężeń i przemieszczenia redlicy. Uzyskane wyniki pozwoliły na poznanie zależności pomiędzy siłami obciążającymi układ, a prędkością i głębokością redlicy podczas pracy w środowisku gruntowym. Uzyskane dane mogą być wykorzystane zarówno do obliczenia nacisków gruntu na powierzchnię redlicy w celu wyznaczenia intensywności zużywania ściernego jak i do obliczeń wytrzymałościowych dźwigni redlicznych.

16

Monitorowanie maszyn do obróbki ziemniaków za pomocą ,,bulwy elektronicznej" PMS-60

63%

Czerko Z. , Nowacki W.

Inżynieria Rolnicza

|

2005

|

tom R. 9, nr 1

49--55

PL

Ziemniaki podczas zbioru i obróbki w przechowalni poddane są różnego rodzaju uderzeniom mechanicznym. Efektem tych mechanicznych oddziaływań na bulwy są uszkodzenia mechaniczne zewnętrzne i wewnętrzne. "Ziemniak elektroniczny" (PMS-60) może pomóc zidentyfikować punkty na linii obróbczej, gdzie mogą wystąpić uszkodzenia mechaniczne. Badania własne były przeprowadzone na linii obróbczej ziemniaków jadalnych w przechowalni ziemniaków. W skład linii wchodził zasobnik dozujący, sortownik, szczotkarka, stół selekcyjny, paczkowarka. Podczas testowania określano maksymalną siłę uderzenia, sumę sił oraz ilość uderzeń przekraczających 25 N. Na całej linii obróbczej było 10 spadków z jednej maszyny na drugą. Wysokość spadków wynosiła od 30 do 60 cm, a ostatni spadek z paczkowarki do siatki wynosił 120 cm. Średnia wartość siły maksymalnej na tych spadkach wynosiła 40-60 N. Największe siły wystąpiły na paczkowarce komputerowej w ostatniej fazie, kiedy ziemniaki spadały do siatki (80-90 N).

XX

Potato tubers are subjected to all sorts of mechanical stress when harvested and later handled in the store facilities. The effect of machinery parts is to cause mechanical damage of the flesh such as cracks and bruises. The electronic potato system (PMS-60) allows for measuring forces which the crop is subjected to and helps to identify points on the handling lines where mechanical damage occurs. Tests were carried out on processing lines for table potatoes in a store facility. The lines included a grader, a dosing hopper, a brusher, a selection table and bagging device. When handling lines were tested with PMS-60, the values determined included the maximum impact force, the total sum of impact forces, the average force value, and the number of impacts over 25 N. There were 10 drops on the processing line. The height of drops was from 30 to 60 cm and the last drop from bagger into sack was 120 cm. The maximum impact force on these machines was from 40 to 60 N. the highest force during the final fase – from bagger into sack drop (80-90 N).

17

Zagadnienie oceny interoperacyjności związku taktycznego

51%

Szydłowski A.

Biuletyn Wojskowej Akademii Technicznej

|

2001

|

tom Vol. 50, nr 2-3

173-196

PL

Artykuł przedstawia rezultaty prac nad adaptacją metody SWOT, znanej z zarządzania strategicznego, do oceny stanu interoperacyjności związku taktycznego. Prace te stanowią metodologiczne rozwinięcie dotych czas przeprowadzonych badań w celu zidentyfikowania istoty interoperacyjności.

EN

The paper presents the results of researche on adaptation of the SWOT methodology to estimate the interoperability of military units. The methodology is known in the Strategic Management. The paper contains the main conclusions about the essence of interoperability. The groups of measurement parameters of interoperability have been proposed. The procedures of interoperability standards have been described and shown at the example.

18

Energia i siły powodowane eksploatacją górniczą

51%

Niemiec T.

Przegląd Górniczy

|

2015

|

tom T. 71, nr 3

55--63

PL

Liczne teorie opisują deformacje górotworu i powierzchni powodowane eksploatacją górniczą w postaci tak zwanych wskaźników deformacji. Znając ruch punktu w przestrzeni i czasie, można w prosty sposób wyprowadzić wszystkie te wskaźniki, a przypisując przemieszczającemu się punktowi masę oraz znając jego prędkość - otrzymać można wskaźniki dynamiczne, które opisują siły oddziałujące na zbiór punktów - czyli np. obiekt budowlany. Rozważania zilustrowano przykładami obliczeniowymi. Rysunki przedstawiają używane w praktyce wskaźniki oraz zdefiniowane w niniejszej pracy wskaźniki dynamiczne - związane z występującą siłą w danym punkcie i czasie.

XX

Numerous theories describe the rock mass and surface deformations caused by mining exploitation in the form of so-called deformation indicators. Knowing the point motion in space and time, all these indicators can be easily determined. Assuming the mass and knowing the velocity of displacing point, the dynamic indicators that describe the forces acting on the set of points - that is e.g. building object - can be obtained. The considerations are illustrated with computational examples. Drawings show the indicators used in practice and dynamic indicators defined in this paper - related to the force occurring in the determined point and time.

19

Wybrane elementy zasobów logistycznych wykorzystywanych w sytuacjach kryzysowych

51%

Karwacka K. , Kowalska M. , Domański P.

Gospodarka Materiałowa i Logistyka

|

2016

|

tom nr 12

298--309

PL

W niniejszym artykule podjęto próbę zdefiniowania słowa logistyka z położeniem nacisku na wykorzystywane bazy danych sił i środków szczebla wojewódzkiego. Artykuł jest próbą usystematyzowania zagadnień związanych z organizacją zabezpieczenia logistycznego z uwzględnieniem koncepcji zarządzania bezpieczeństwem. Zostały w nim przedstawione podstawowe definicje dotyczące systemu Państwowe Ratownictwo Medyczne, a także dane w zakresie liczby szpitalnych oddziałów ratunkowych, centrów urazowych oraz zespołów ratownictwa medycznego znajdujące się na obszarze województwa pomorskiego.

EN

In this article we will attempt to define the word logistics with an emphasis on the used database of forces and means of the voivodship level. Article will attempt to systematize issues connected with the organization of logistical support including the concept of security management. Basic definitions for the system of National Emergency medical services will be presented, as well as data in terms of the number of hospital emergency departments, trauma centers, and medical rescue teams located in the voivodship of Pomerania.