Wyniki wyszukiwania - Biblioteka Nauki

1

Two-weight norm inequalities for maximal functions on homogeneous spaces and boundary estimates

100%

Luís Zani S.

Studia Mathematica

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1997

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tom 126

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nr 1

67-94

EN

Let D be an open subset of a homogeneous space(X,d,μ). Consider the maximal function $M_φ f(x) = sup1/φ(B) ʃ_{B∩∂D} |f|dν$, x∈ D, where the supremum is taken over all balls of the form B = B(a(x),r) with r > t(x) = d(x,∂D), a(x)∈ ∂D is such that d(a(x),x) < 3/2 t(x)$ and φ is a nonnegative set function defined for all Borel sets of X satisfying the quasi-monotonicity and doubling properties. We give a necessary and sufficient condition on the weights w and v for the weighted norm inequality (0.1) $(ʃ_D [M_φ(f)]^q wdμ)^{1/q} ≤ c(ʃ_{∂D} |f|^p vdν)^{1/p}$ to hold when 1 < p < q < ∞, $σdν = v^{1-p'}dν$ is a doubling weight, and dν is a doubling measure, and give a sufficient condition for (0.1) when 1 < p ≤ q < ∞ without assuming that σ is a doubling weight but with an extra assumption on φ. Another characterization for (0.1) is also provided for 1 < p ≤ q < ∞ and D of the form Y×(0,∞), where Y is a homogeneous space with group structure. These results generalize some known theorems in the case when $M_φ$ is the fractional maximal function in $ℝ^{n+1}_+$, that is, when $M_φ f(x,t) = M_γ f(x,t) = sup_{r>t} 1/(ν(B(x,r))^{1-γ}) ʃ_{B(x,r)} |f|dν$, where $(x,t) ∈ ℝ^{n+1}_+$, 0 < γ < 1, and ν is a doubling measure in $ℝ^n$.

2

Weighted Maximal Inequalities for Martingale Transforms

100%

Brzozowski M. , Osękowski A.

Probability and Mathematical Statistics

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2021

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tom Vol. 41, Fasc. 1

89--114

EN

We study the weighted maximal L1-inequality for martingale transforms, under the assumption that the underlying weight satisfies Muckenhoupt’s condition A∞ and that the filtration is regular. The resulting linear dependence of the constant on the A∞ characteristic of the weight is optimal. The proof exploits certain special functions enjoying appropriate size conditions and concavity.

3

An Extension of Kotzig’s Theorem

100%

Aksenov V. A. , Borodin O. V. , Ivanova A. O.

Discussiones Mathematicae Graph Theory

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2016

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tom 36

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nr 4

889-897

EN

In 1955, Kotzig proved that every 3-connected planar graph has an edge with the degree sum of its end vertices at most 13, which is tight. An edge uv is of type (i, j) if d(u) ≤ i and d(v) ≤ j. Borodin (1991) proved that every normal plane map contains an edge of one of the types (3, 10), (4, 7), or (5, 6), which is tight. Cole, Kowalik, and Škrekovski (2007) deduced from this result by Borodin that Kotzig’s bound of 13 is valid for all planar graphs with minimum degree δ at least 2 in which every d-vertex, d ≥ 12, has at most d − 11 neighbors of degree 2. We give a common extension of the three above results by proving for any integer t ≥ 1 that every plane graph with δ ≥ 2 and no d-vertex, d ≥ 11+t, having more than d − 11 neighbors of degree 2 has an edge of one of the following types: (2, 10+t), (3, 10), (4, 7), or (5, 6), where all parameters are tight.

4

Weighted weak-type inequality for martingales

100%

Osękowski A.

Bulletin of the Polish Academy of Sciences. Mathematics

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2017

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tom Vol. 65, no. 2

165--175

EN

Let X = (Xt) t ≥ 0 be a bounded martingale and let Y = (Yt) t ≥ 0 be differentially subordinate to X. We prove that if 1 ≤ p < ∞ and W = (Wt) t ≥ 0 is an Ap weight of characteristic [W] Ap, then ∥Y∥Lp, ∞ (W) ≤ Cp [W]Ap∥X∥L∞(W). The linear dependence on [W]Ap is shown to be the best possible. The proof exploits a weighted exponential bound which is of independent interest. As an application, a related estimate for the Haar system is established.

5

Application of TOPSIS and PIV methods for multi-criteria decision making in hard turning process

100%

Trung D. D.

Journal of Machine Engineering

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2021

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tom Vol. 21, No. 4

57--71

EN

In this study, TOPSIS and PIV methods were applied for multi-criteria decision making in hard turning process. Experiments have been conducted in accordance with an experimental matrix designed by the Taguchi method with a total of twenty-seven experiments. At each experiment, the values of coolant concentration, nose radius, coolant flow, cutting velocity, feed rate and depth of cut have been changed. Surface roughness, flank wear and roundness error have been selected as output criteria. The weights of criteria have been determined by three methods, inclusive of Equal weight, ROC weight and Entropy weight. The combination of multi-criteria decision-making methods with three weighting methods gives six ranking options of the experiments. The purpose of ranking the experiments is to find the experiment at which the three output parameters are ensured to have the minimum value simultaneously.

6

Weak type estimates for operators of potential type

100%

Wheeden R. L. , Zhao S.

Studia Mathematica

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1996

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tom 119

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nr 2

149-160

EN

We derive two-weight weak type estimates for operators of potential type in homogeneous spaces. The conditions imposed on the weights are testing conditions of the kind first studied by E. T. Sawyer [4]. We also give some applications to strong type estimates as well as to operators on half-spaces.

7

Greedy Algorithm with Weights for Decision Tree Construction

100%

Moshkov M. J.

Fundamenta Informaticae

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2010

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tom Vol. 104, nr 3

285-292

EN

An approximate algorithm for minimization of weighted depth of decision trees is considered. A bound on accuracy of this algorithm is obtained which is unimprovable in general case. Under some natural assumptions on the class NP, the considered algorithm is close (from the point of view of accuracy) to best polynomial approximate algorithms for minimization of weighted depth of decision trees.

8

Modelowanie elementów układów pomiarowych przeniesienia siły z zastosowaniem netody elementów skończonych

100%

Osiński J. , Samborski T. , Zbrowski A.

Problemy Eksploatacji

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1998

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tom nr 4

209-225

PL

W artykule przedstawiono komputerową symulację wpływu obciążenia na odkształcenie elementu płytowego zastosowanego w układzie pomiarowym przeniesienia siły. Układ ten wykorzystuje zależność pomiędzy obciążeniem a odkształceniami zachodzącymi w płycie. Zamieszczono wyniki rozważań analityczno - teoretycznych w postaci obliczeń komputerowych Metodą Elementów Skończonych za pomocą pakietu ANSYS 5,3, które następnie zweryfikowano praktycznie na stanowisku badawczym - maszynie wytrzymałościowej INSTRON 5582.

EN

In this paper the authors present the results of computer simulation of an influence of load on plate element deflection in the force measuring system. The system way of operation employs a correlation between the load and plate deflection. The authors compare the results of theoretical predictions with the data obtained using the finite element method realised by the ANSYS computer package. All the results have been verified on the INSTRON stress machine.

9

Pointwise multipliers for reverse Holder spaces

100%

M. Buckley S.

Studia Mathematica

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1994

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tom 109

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nr 1

23-39

EN

We classify weights which map reverse Hölder weight spaces to other reverse Hölder weight spaces under pointwise multiplication. We also give some fairly general examples of weights satisfying weak reverse Hölder conditions.

10

Selected parameters of the work of speed limiter in line straining system in a frictional lift

100%

Lonkwic P. , Szydło K.

Advances in Science and Technology. Research Journal

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2014

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tom Vol. 8, nr 21

73--77

EN

The article presents the analysis of selected work parameters of speed limiter in line straining system. We analyzed the effect of changing the geometrical conditions of the new solution for the speed limiter in line straining system upon the working conditions in frictional lift braking system. Within the conducted simulations of the work of the system, which is responsible for lift braking with a tension with spring, a test bed was prepared, which simulated the work of tension-rope-limiter system. The tests were performed in the conditions reflecting the work of a lifting appliance. Analyzing the results obtained through empirical calculations, we can conclude that there is a possibility of applying the spring to eliminate the weight.

11

Short term secular change in body size and physical fitness of youth 7–15 years in Southwestern Poland: 2001–2002 and 2010–2011

88%

Ignasiak Z. , Sławińska T. , Malina R. M.

Anthropological Review

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2016

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tom 79

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nr 3

311-329

EN

Short term secular change in body size and physical fitness of Polish youth 7-15 years of age resident in an industrial region of Lower Silesia in southwestern Poland was considered across two surveys, 2001-2002 and 2010-2011. Subjects were students in the same schools in both surveys 1892 boys and 1992 girls in the first and 1237 boys and 1236 girls in the second. In addition to height and weight, performances in six fitness tests were measured in each survey. Height, weight and BMI increased significantly across surveys. Statistically controlling for secular gains in height and weight, only static strength (hand grip) and running speed - agility (shuttle run) improved significantly between surveys in three age groups (7-9, 10-12, 13-15 years), while explosive power (standing long jump) showed negligible changes except in girls 13-15 years among whom performances declined significantly. Speed of upper limb movement (plate tapping), flexibility (sit and reach) and trunk strength (sit-ups) declined between surveys, except for trunk strength in boys 13-15 years which did not change. In conclusion, after statistically controlling for secular gains in body size, physical fitness items changed variably over the decade.

12

5-Stars of Low Weight in Normal Plane Maps with Minimum Degree 5

88%

Borodin O. V. , Ivanova A. O. , Jensen T. R.

Discussiones Mathematicae Graph Theory

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2014

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tom 34

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nr 3

539-546

EN

It is known that there are normal plane maps M5 with minimum degree 5 such that the minimum degree-sum w(S5) of 5-stars at 5-vertices is arbitrarily large. In 1940, Lebesgue showed that if an M5 has no 4-stars of cyclic type (5, 6, 6, 5) centered at 5-vertices, then w(S5) ≤ 68. We improve this bound of 68 to 55 and give a construction of a (5, 6, 6, 5)-free M5 with w(S5) = 48

13

Sample allocation decisions for program evaluation: a case of multiplicative effect on units due to the developmental initiatives carried out in a phased manner

88%

Pandey R.

Folia Forestalia Polonica. Series A . Forestry

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2010

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tom 52

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nr 2

14

Anthropometric profile of the top-class male handball players participating in the Olympic Games Tokyo 2020

88%

Krawczyk P. , Sieńko M.

Acta of Bioengineering and Biomechanics

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2023

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tom Vol. 25, no. 2

69--77

EN

The purpose of the study was to try to determine the factors that differentiate the height, weight, BMI and age of high-level handball players participating in the Tokyo 2020 Olympic Games. Methods: The study included handball players participating in the Tokyo 2020 Olympic Games. The study material consisted of data on athletes’ body height, body weight, age and BMI. The collected study material was analyzed about the position of the game, quarter and semester of the birth, continental location of the country and geographical region. In parametric distribution, Student’s t-test and ANOVA were used. In non-parametric variables, the Mann–Whitney U-test and the Kruskal–Wallis test were used. Results: The highest average heights, weights and BMIs were found in players playing in the pivot position, while the lowest were found in wing players. Interactions were shown within the body weight and BMI of the athletes. Players from Europe have the highest weight and BMI in the second semester of birth, while other players’ highest results were in the first semester. Conclusions: The factors that most strongly differentiate body height, body weight, and BMI are playing positions. Factors that differentiate height and weight are the continental location and region of the country represented.

15

Minimal vertex degree sum of a 3-path in plane maps

88%

Borodin O.

Discussiones Mathematicae Graph Theory

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1997

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tom 17

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nr 2

279-284

EN

Let wₖ be the minimum degree sum of a path on k vertices in a graph. We prove for normal plane maps that: (1) if w₂ = 6, then w₃ may be arbitrarily big, (2) if w₂ < 6, then either w₃ ≤ 18 or there is a ≤ 15-vertex adjacent to two 3-vertices, and (3) if w₂ < 7, then w₃ ≤ 17.

16

Regression equations for intravital assessment of breast muscles weight of chickens

88%

Michalik D. , Bochno R. , Wilkiewicz-Wawro E. , Lewczuk A. , Makowska M.

Natural Sciences

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2001

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tom 09

17

Children brain weight in various pathological conditions

88%

Kraszpulska B.

Folia Morphologica

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1996

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tom 55

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nr 4

18

The relation between selected health behaviour and body mass index amongst adolescents living in urban and rural areas in south-western Poland

75%

Czajka K. , Fiszer K. , Kolodziej M.

Roczniki Państwowego Zakładu Higieny

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2013

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tom 64

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nr 2

EN

Background. Changes to the body and its proportions, especially body mass, are frequently and critically assessed by the young according to peer pressure and opinions prevalent in their living and home surroundings, as well as through role models created by the media; particularly those promoting fashions for having a slim figures. The desire to achieve this ideal, is thus responsible for adolescents undertaking a variety of actions/behaviour to regulate their body weight. Objective. To compare healthy lifestyle behaviour in secondary school pupils living in towns and the countryside who have variable weights and heights associated with a self-assessment of body mass. Material and Methods. Subjects were n=1,279 pupils aged 13-15 years, attending secondary school. Those from the countryside environments were n=273 (136 boys and 137 girls), whilst those from urban areas, (towns) were n=1,006 (512 boys and 494 girls). Both weights and heights were measured and the Body Mass Index (BMI) determined. Threshold values for overweight, obesity and underweight, were used to assign BMI groups according to the procedure of Cole et al. Perceptions on how subjects assessed their body weight and remedial actions so arising, were surveyed using the Youth Risk Behaviour Survey (YRBS) questionnaire. The relationships between the factors studied were subjected to log-linear analysis and their significance evaluated by Chi2 test using a significance level of p≤ 0.05. Results. No significant differences were found in the observed frequencies of overweight, obesity and underweight groups between students from the different environments studied. Pupils having a normal body mass constituted 68.9% of total subjects. There were also no differences seen in body weight perception between the various environments. Approximately 70% of subjects properly assessed their own body mass, however the methods of its assessment differed between boys and girls. The main ways adopted for regulating body mass was found to be exercise and diet in both student groups. Significantly more girl pupils living in towns, (54.9%) did physical exercises, aimed at weight reduction, compared to those living in the countryside (43.8%). Conclusions. Only small differences in observed frequencies of height-weight were seen between urban and rural dwelling pupils; the same being true for lifestyle behaviour in controlling weight. Irrespective of residence, two thirds of pupils, aged 13-16 years, correctly assessed their own body mass. In children and adolescents, improving self-awareness of body proportions can be achieved through educating on what the significance of having a healthy BMI is, effective ways of its estimation and safe methods for regulation.

PL

Wprowadzenie. Zmieniające się proporcje ciała a zwłaszcza masa ciała, często poddawane są przez młodzież ocenie, na którą ma wpływ opinia najbliższego środowiska oraz wzorce kreowane przez środki masowego przekazu promujące modę na szczupłą sylwetkę. Chęć osiągnięcia wzorcowej sylwetki skłania do podejmowania przez młodzież działań ukierunkowanych na regulację masy ciała. Cel. Celem badań było porównanie zachowań zdrowotnych związanych z postrzeganiem własnej masy ciała uczniów miejskich i wiejskich gimnazjów o zróżnicowanych proporcjach wagowo-wzrostowych. Materiał i metody. Materiał obejmował dane pomiarowe i ankietowe 1279 uczniów w wieku 13-16 lat, z dwóch różnych środowisk: wiejskiego (273 uczniów – 136 chłopców i 137 dziewcząt) i miejskiego (1006 osób – 512 chłopców i 494 dziewcząt). U młodzieży zmierzono wysokość i masę ciała, wyliczono wskaźnik BMI. Wartości graniczne dla nadwagi, otyłości oraz niedowagi posłużyły do wyznaczenia grup BMI. Z kwestionariusza Youth Risk Behavior Survey (YRBS) uzyskano informacje o ocenie własnej masy ciała oraz działaniach podejmowanych w celu jej zmiany. Do ustalenia związków pomiędzy analizowanymi czynnikami, wykorzystano analizę log-liniową. Istotność statystyczną otrzymanych zależności oceniano testem Chi2 na poziomie istotności p≤ 0,05. Wyniki. W badaniach nie stwierdzono istotnych różnic w częstości występowania nadwagi, otyłości oraz niedowagi między uczniami zamieszkującymi odmienne środowiska. Osoby z właściwą masą ciała stanowiły 68,9% badanych. Nie odnotowano różnic międzyśrodowiskowych w samoocenie masy ciała. Około 70% badanych właściwie oceniało własną masę ciała, lecz chłopców i dziewczęta różnił sposób jej oceny. Ćwiczenia fizyczne i dieta w obu badanych środowiskach były wskazywane jako główne metody regulacji proporcji wagowo-wzrostowych. Badania dowiodły, że dziewczęta szkół miejskich (54,9%) istotnie częściej w porównaniu do rówieśniczek ze szkół wiejskich (43,8%) wykonywały ćwiczenia fizyczne ukierunkowane na regulację masy ciała. Wnioski. Zaobserwowano niewielkie różnice między środowiskami – miejskim i wiejskim - pod względem proporcji wagowo- wzrostowych oraz zachowań zdrowotnych związanych z masą ciała. Niezależnie od miejsca zamieszkania, dwóch na trzech uczniów w wieku 13-16 lat prawidłowo oceniało własną masę ciała. Poprawę świadomości wśród dzieci i młodzieży w zakresie własnych proporcji ciała, można dokonać poprzez edukację znaczenia prawidłowej masy ciała dla zdrowia, sposobów jej oceny oraz skutecznych i bezpiecznych metod jej regulacji.

19

Relationship between backfat androstenone level and the weight of boar genital organs

75%

Tuz R. , Koczanowski J. , Migdal W. , Klocek C.

Annals of Animal Science. Supplement

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2005

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nr 2

20

Fat thickness and the longest back muscle measurement of carcasses of fatteners slaughtered at different weight

75%

Winarski R. , Wajda S.

Polish Journal of Natural Sciences

|

2009

|

tom 24

|

nr 2

113-121

EN

The research was conducted on 286 fattener carcasses chosen from mass population in three different regions of the country. On the carcasses, fat thickness measurements were performed on the carcass cross section as well as fat and the longest back muscle thickness measurements on two cross sections of the loin. Carcasses, depending on their weight, were divided into three groups, i.e. of the average weight of about 70, 80 and 90 kg. Research showed that the increase of carcass weight by about 10 kg in the case of fatteners bought by meat plants caused statistically significant increase of fat thickness and measurement results of the longest back muscle in all measured points. The increase of carcass weight from 70.0 to 80.0 kg caused relatively small increase of fat thickness (about 2 mm), and higher increase of the longest back muscle height (about 5mm), however the increase of carcass weight from 80.0 to 90.0 kg, influenced greater increase of fat thickness (about 5 mm), and smaller increase of the longest back muscle (about 2 mm). In the classification system, where one takes into account fat thickness and the longest back muscle height when estimating the meat percentage, we may expect small decrease of carcass meatiness at carcass weight increase to 85.0 kg, and having exceeded this weight, greater decrease of carcass meat percentage may be expected.

PL

Badania przeprowadzono na 286 tuszach tuczników wybranych z pogłowia masowego w trzech różnych regionach kraju. Wykonano pomiary grubości słoniny na przepołowieniu tuszy oraz pomiary grubości słoniny i mięśnia najdłuższego grzbietu na dwóch przekrojach polędwicy. Tusze podzielono na trzy grupy, tj. o średniej masie ok. 70, 80 i 90 kg. Badania wykazały, że wzrost masy tusz (tuczników skupowanych przez zakłady mięsne) o ok. 10 kg, spowodował statystycznie istotny wzrost grubości słoniny i wartości pomiarów mięśnia najdłuższego grzbietu we wszystkich badanych punktach. Wzrost masy tusz od 70,0 do 80,0 kg powodował stosunkowo niewielki wzrost grubości słoniny (ok. 2 mm), a większy wzrost wysokości mięśnia najdłuższego grzbietu (ok. 5mm). Wzrost masy tusz od 80,0 do 90,0 kg wpłynął natomiast na większy wzrost grubości słoniny (ok. 5 mm), a mniejszy mięśnia najdłuższego grzbietu (ok. 2 mm). W systemie klasyfikacji, w którym w trakcie określania mięsności tusz bierze się pod uwagę grubość słoniny i wysokość mięśnia najdłuższego grzbietu, można się spodziewać niewielkiego obniżenia mięsności tusz, gdy wzrasta ich masa do 85,0 kg. Po jej przekroczeniu można spodziewać się większego obniżenia mięsności tusz.