Wyniki wyszukiwania - Biblioteka Nauki

1

Multi - material design optimization of a bus body structure

100%

Korta J. , Uhl T.

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2013

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tom Vol. 20, No. 1

139--146

EN

In the recent years the safety and eco-friendliness have gained much of attention of the automotive stakeholders. These two characteristics are especially important in the case of mass transportation vehicles, such as buses or coaches, which are in continues use for long periods of time, covering significant distances. In such situations, the economical aspects play major role for the transportation companies which try to minimize operational costs of their fleet, by choosing vehicles with reduced fuel consumption. In order to obtain improvements in all the mentioned areas and hence to strengthen their position on the market, bus manufacturers have recently turned their attention to multimaterial design strategies. Structures built in that manner consist not only of regular steel parts, but contain also a mix of components made from various lightweight materials like aluminum alloys or composites, which allow for significant reduction in vehicle curb weight. However, due to the differences in mechanical characteristics which are especially evident in the case of laminates, the material substitution is not a straightforward task. In order to find the material distribution pattern that meets all the requirements, a great number of prototypic numerical models must be prepared and tested. To ease the search for the final solution, optimization techniques can be applied into the design process, allowing for automatic design modifications and assessment of the obtained results. The paper presents an attempt of enhancing the operational characteristics of a bus body structure with simultaneous reduction in the structural weight. In order to find the optimal component configuration, a multimaterial optimization was employed and supplemented by sensitivity and robustness analyses. Such a technique helps to discriminate the over-optimized solutions that are often pointed out as the most desirable by the optimization algorithms which neglect the uncertainties of the analysed system.

2

DOES COGNITIVE TRAINING MAKE NUTRITION AND EXERCISE PROGRAMS FOR WEIGHT REDUCTION MORE SUCCESSFUL?

100%

Paasch R.

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nr 1

17-24

EN

By carrying out an intervention study including a two-month period of executing measures and an observation period of another two months, the hypothesis stating that cognitive training makes weight reduction programs more successful is to be confirmed. The measures are introduced in a fitness facility. This study involved a cooperation with Mrs. Sporty. The target group are overweight women from the age of 30 onwards. From this target group of overweight women from the age of 30 onwards, three groups of 25 participants each are randomized. Two groups of 25 participants each are assembled from various Mrs. Sporty facilities in Flensburg, Schleswig, Rendsburg, and Husum. A third group of overweight non-athletes is generated over the press, flyers, and posters. All groups equally take part in one or, if required, two introductory individual interviews at the beginning in which initial data is gathered by way of a questionnaire that was developed for the study and first measurements are taken regarding BMI, waist size, and body fat content. Moreover, the participants’ individual situation and their specific problems are discussed and the intervention is adjusted accordingly. For participants that also receive cognitive training, mental measures that are in accordance with the concept developed and presented for the study are additionally integrated in the interviews as well as in the questionnaire and conducted theoretically and practically throughout the entire procedure.

3

Unconventional Methods of Joining Composites and Metals in the Context of Weight Reduction of Car Bodies

88%

Sabadka D. , Kender Š.

Advances in Science and Technology. Research Journal

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2023

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tom Vol. 17, no 1

230--242

EN

One of the basic trends in the automotive industry today is to achieve the most acceptable ratio between the total weight of the car to its overall performance and utility properties. Reducing the weight of cars is largely due to the use of new materials, where composite materials offer a wide space for their application. Composite materials have their specific properties which is very beneficial in reducing the total weight. Another advantages is strength, stiffness, low fiber density, the ability to form them into any shape based on the required applications. One of the challenges associated with the use of composite materials is the search for new technological possibilities of joining composite materials with metals. These include technologies as for example riveting, ultrasonic welding, but especially gluing. Bonding is currently one of the most preferred ways of joining composite materials. The paper deals with testing of technology of bonding composite materials with metals used in the manufacture of automobiles and a comparison of individual results obtained from the experiment.

4

Obróbka cieplno-mechaniczna stopów Mg

75%

Sułkowski B.

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2021

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tom nr 9-10

44--48

PL

Stopy magnezu ze względu na mały ciężar właściwy są stosowane w tych gałęziach przemysłu, w których redukcja masy jest kluczowa. Mowa tutaj o przemyśle samochodowym, lotniczym i kosmicznym. Wadami stopów magnezu są podatność na korozję oraz słabe własności mechaniczne. Wytrzymałość na rozciąganie w stopach magnezu rzadko przekracza 300 MPa i bardzo szybko maleje wraz ze wzrostem temperatury.

EN

Due to their low specific weight, magnesium alloys are used in industries where weight reduction is crucial. We are talking about the automotive, aerospace and aerospace industries. The disadvantages of magnesium alloys are susceptibility to corrosion and poor mechanical properties. The tensile strength in magnesium alloys rarely exceeds 300 MPa and decreases very quickly as the temperature increases.

5

Biologicznie aktywne składniki żywności wspomagające redukcję masy ciała. Cz. II. Mechanizmy działania

75%

Waszkiewicz-Robak B. , Świderski F. , Serafin P.

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tom T. 61, nr 8

60-64

PL

W artykule scharakteryzowano wybrane substancje bioaktywne przeznaczone do stosowania w dietach redukujących masę ciała, pogrupowane (w zależności od mechanizmu ich oddziaływania na organizm) następująco: zwiększające uczucie sytości, absorbujące tłuszcz i/lub hamujące jego wykorzystanie w organizmie, przyspieszające spalanie tłuszczu lub hamujące syntezę tłuszczu (inhibitory lipazy), modulujące metabolizm węglowodanów. Składniki bioaktywne eliminujące wodę z organizmu, o działaniu moczopędnym i przeczyszczającym oraz zwiększające termogenezę scharakteryzowano w części I artykułu (PS nr 7/2007).

EN

The article has aimed to characterize selected bioactive substances used in the diets supporting weight reduction, classified according to purported mechanism, such as increasing the feeling of satiety, absorbing fat and/or blocking dietary fat absorption, increasing fat oxidation or reducing fat synthesis, modulating carbohydrate metabolism. Bioactive components increasing water elimination of diuretic and purgative activity as well as increasing energy expenditure were characterized in the first part of the article (PS No 7/2007).

6

Proposal of PC unit for frequent transfer and manipulation by air transport

63%

Sestak J. , Poor P. , Takac P. , Ondrejova L.

Intercathedra

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2011

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tom 27

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nr 4

EN

This work presents the realization of a PC unit for air transport focusing on design of particular parts and the design of the whole box. Particular variants of solution in this area are processed in form of 3D models, which is essential for the final composition of the PC unit as a harmonic unit with an eye-catching design. The proposal originated from the real need for computer transport by air. All aspects of this transport have been analyzed in detail and incorporated into this proposal.

7

Possibility of optimizing the chassis of modern passenger wagons in relation to reduction of their weight

63%

Gazdulski T. , Lewiński J. , Far M.

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tom Nr 4

27--34

EN

The requirements imposed on modernized and new rail vehicles are increasing. They are related to safety and environmental protection, and aimed at improving the travel operational parameters and comfort. Therefore, the weight reduction of rail vehicles plays an increasingly important role in the designing process. The paper presents the construction of the chassis of modern passenger coaches and specification of the masses of particular components of the coach chassis. The directions of development of the passenger coach chassis are proposed, with a view to reduce its weight.

PL

Wymagania stawiane zarówno modernizowanym jak i nowym pojazdom szynowym są coraz większe. Dotyczą one bezpieczeństwa i ochrony środowiska, a z drugiej strony polepszenia parametrów eksploatacyjnych oraz komfortu podróżowania. Redukcja masy pojazdów szynowych odgrywa coraz większą rolę podczas procesu konstruowania. W artykule przedstawiono konstrukcję podwozi współczesnych wagonów osobowych, dokonano analizy mas poszczególnych elementów podwozia wagonowego oraz zaproponowano kierunki rozwoju budowy konstrukcji podwozi wagonów osobowych w odniesieniu do redukcji masy.

8

Biologicznie aktywne składniki żywności wspomagające redukcję masy ciała. Cz. I

63%

Waszkiewicz-Robak B. , Świderski F. , Serafin P.

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tom T. 61, nr 7

28-30

PL

Substancje biologicznie aktywne wspomagające redukcję masy ciała są oferowane konsumentom jako suplementy diety lub środki spożywcze specjalnego przeznaczenia żywieniowego. Scharakteryzowano asortyment tych preparatów znajdujących się na polskim rynku oraz oceniono ich popularność wśród konsumentów. Większą wiedzę z tego zakresu wykazują kobiety. Najbardziej popularnymi preparatami do stosowania w redukcji masy ciała są: czerwona i zielona herbata, preparaty chromu oraz L-karnityna. W artykule przedstawiono pozytywne i negatywne aspekty stosowania substancji bioaktywnych pomagających w redukcji masy ciała. W cz. I scharakteryzowano składniki bioaktywne eliminujące wodę z organizmu, mające działanie moczopędne i przeczyszczające oraz zwiększające termogenezę. W części II omówione zostanie działanie pozostałych grup substancji bioaktywnych stosowanych w redukcji masy ciała.

EN

The bioactive substances used in preparations supporting weight reduction are offered in a diversified form: as dietary supplements or food products of special dietary appropriation. The study has characterized the assortment of these preparations on the Polish market and assessed consumers' knowledge about them. Women showed a greater knowledge in this field. The most popular preparations used in weight reduction among the Polish society are: red and green tea, chromium preparations and L-carnitine. The thesis also presents positive and negative aspects of such treatments.

9

Overweight in relation to motor activity and stress level of university students

51%

Zuskova K. , Bukova A. , Bakalar P. , Brtkova M. , Vojtasko L. , Hancova M.

Prace Naukowe Akademii im. Jana Długosza w Częstochowie. Kultura Fizyczna

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2013

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tom 12

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nr 2

EN

A current problem of the population nowadays appears to be the lack of motor activity, the increase in BMI and the growth in stressogenic factors in the way of life of the population. This in turn affects the quality of human life and health. On a sample of university undergraduates (794 men and 1,169 women) we were observing the relation between overweight, namely the level of BMI gained via somatometric measurement, and the amount of subjectively evaluated level of motor activity, in their relation to the subjectively perceived extent of stress in their lifestyle, using the method of questionnaire. The results in both genders confirmed the existing relationship between BMI values and the degree of physical activity as well as the correlation between motor activity and subjectively perceived stress. As a result, the relationship between the variables motor activity and stress level did not prove significant.

PL

Współcześnie obserwuje się narastanie problemu deficytu aktywności fizycznej, wzrost wskaźnika BMI oraz coraz większy udział czynników stresu w sposobie życia społeczeństwa. Tendencje te z kolei wpływają negatywnie na jakość życia i zdrowie człowieka. Badaniom somatometrycznym poddano grupę studentów wyższych uczelni (794 mężczyzn i 1169 kobiet), aby określić związek pomiędzy nadwagą – konkretnie wysokim poziomem BMI – a stopniem aktywności fizycznej i subiektywnie postrzeganym poziomem stresu. Opinie na ten temat zebrano w badanej grupie za pomocą kwestionariusza. Wyniki – uporządkowane wg kryterium płci – potwierdziły związek między BMI i stopniem aktywności fizycznej oraz subiektywnym postrzeganiem stresu, nie stwierdzono natomiast związku między aktywnością fizyczną a poziomem stresu.

10

Opracowanie konstrukcji i technologii obróbki innowacyjnej zasuwy energetycznej

51%

Stanisław A. , Miko E. , Makieła W. , Nowakowski Ł. , Skrzyniarz M. , Jarema M. , Świderski J. , Dobrowolski T. , Wójcik C.

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tom R. 93, nr 12

6--10

EN

The article presents the results of the research project in cooperation between Kielce University of Technology and Chemar Armatura Sp. z o.o. Project co-financed by european funds was entitled: “Putting into the production of an innovative series of energy wedge gate which is equipped with two-part wedge and swing disk, as a result of R&D works at Chemar Armatura”.

PL

W artykule przedstawiono wyniki pracy badawczej prowadzonej przez Politechnikę Świętokrzyską w Kielcach oraz Chemar Armatura Sp. z o.o., dofinansowanej z funduszy europejskich w ramach projektu pt. „Wdrożenie do produkcji w firmie Chemar Armatura innowacyjnego typoszeregu zasuw klinowych wyposażonych w klin dwudzielny z przesuwanymi dyskami wahliwymi, jako wynik zleconych prac B+R”.

11

Effect of phosphate supplementation on metabolic and neuroendocrine responses to exercise and oral glucose load in obese women during weight reduction

51%

Kaciuba-Uscilko H. , Nazar K. , Chwalbinska-Moneta J. , Ziemba A. , Kruk B. , Szczepanik J. , Titow-Stupnicka E. , Bicz B.

Journal of Physiology and Pharmacology

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1993

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tom 44

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nr 4

12

Increased lipogenic potential of rat adipose tissue after repeated dieting - the role of SREBP-1 transcription factor

51%

Kochan Z.

Cellular and Molecular Biology Letters

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2003

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tom 08

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nr 4

EN

Repeated dieting is one of the methods used for weight reduction; however, its effectiveness is questionable. We developed an experimental, rat model of repeated dieting, which mimics the dietary approach used in the treatment of obesity in humans. In this experimental model, despite the lower caloric intake, decreased body mass and reduced fat stores, the lipogenic potential of adipose tissue increased. We observed a substantial increase in fatty acid synthase (a key lipogenic enzyme) gene expression in rat adipose tissue accompanied by a 9-fold increase in the serum insulin level. Fatty acid synthase gene expression is controlled at the transcriptional level by SREBP-1. In this study, a remarkable increase (24-fold) in SREBP-1 protein amount, parallel to that in fatty acid synthase mRNA level, protein concentration and enzyme activity was observed after multiple cycles of fasting-refeeding. Although it is possible that the interactions between transcription factors are more complex, we propose that the pivotal role in the increase of the lipogenic potential of adipose tissue after repeated dieting may be played by SREBP-1.

13

Wplyw diety o niskim indeksie glikemicznym na zmiany skladu ciala i spoczynkowych wydatkow energetycznych u odchudzajacych sie kobiet

44%

Lange E. , Tymolewska-Niebuda B. , Kacperska A.

Bromatologia i Chemia Toksykologiczna

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2009

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tom 42

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nr 3

651-657

14

Design optimization for the weight reduction of 2-cylinder reciprocating compressor crankshaft

38%

Arshad A. , Cong P. , Elsayed Elmenshawy A. A. A. , Blumbergs I.

Archive of Mechanical Engineering

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2021

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tom LXVIII, nr 4

449--471

EN

This study aims to optimize the 2-cylinder in-line reciprocating compressor crankshaft. As the crankshaft is considered the "bulkiest" component of the reciprocating compressor, its weight reduction is the focus of current research for improved performance and lower cost. Therefore, achieving a lightweight crankshaft without compromising the mechanical properties is the core objective of this study. Computational analysis for the crankshaft design optimization was performed in the following steps: kinematic analysis, static analysis, fatigue analysis, topology analysis, and dynamic modal analysis. Material retention by employing topology optimization resulted in a significant amount of weight reduction. A weight reduction of approximately 13% of the original crankshaft was achieved. At the same time, design optimization results demonstrate improvement in the mechanical properties due to better stress concentration and distribution on the crankshaft. In addition, material retention would also contribute to the material cost reduction of the crankshaft. The exact 3D model of the optimized crankshaft with complete design features is the main outcome of this research. The optimization and stress analysis methodology developed in this study can be used in broader fields such as reciprocating compressors/engines, structures, piping, and aerospace industries.

15

Otyłość i choroba ortopedyczna - związek wart zapamiętania

38%

Cline M.

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tom 20

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nr 6