Wyniki wyszukiwania - Biblioteka Nauki

1

SEMI-STRONG AND STRONG FORM OF STOCK MARKET EFFECTIVENESS BASED ON CURRENT EMPIRICAL STUDY

100%

Kowalczuk P.

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nr 1(37)

147-188

EN

The Efficient Market Hypothesis (EMH) still draws attention of capital market participants even though it is over 35 yeas old. This article brings up the issue of semi-strong and strong forms of the EMH. It presents major empirical researches regarding this issue and tries to draw common conclusions. Event studies results do not provide us with a straightforward answer to the question of semi-strong efficiency. The market quickly reacts to dividends announcements, dissemination of analysts' recommendations and equity issues. However, semi-strong efficiency is not supported by earnings announcements studies. The majority of them show too slow market reaction ('drift'). This drift also occurs on Polish equity market (up to 60 days after earnings announcement). Additionally, the smaller the company, the stronger the drift, which suggests that small-cap market is less efficient. Researches concerning strong form of EMH show that there is a group of investors who possess informational advantage over the others. They are referred to as insiders. This fact is contrary to strong efficiency. According to majority of private information studies, neither fund managers nor analysts (even though there are some doubts in their case) possess private information.

2

Budowa, struktura i dynamika gornoreglowego boru swierkowego o charakterze pierwotnym w rezerwacie Romanka w Beskidzie Zywieckim [w okresie kontrolnym 1993-2004]

63%

Karczmarski J. , Kowalczuk P.

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tom 45

39-71

EN

The paper presents dynamics (in the period 1993-2004) of selected parts of upper mountain spruce stand of primeval character growing on the area of reserve Romanka in Beskid Żywiecki Mts. The changes of species composition, volume, DBH and height distribution, storey structure, the share of standing and laying dead trees and number of regeneration as well as the stand volume increment were determined on two sample plots. In the optimum stage (advanced ageing phase) stand volume increased from 465 m³/ha to 500 m³/ha, volume of dead standing trees decreased from 61 m³/ha to 51 m³/ha and volume of downed trees inceased from 49 m /ha to 58 m³/ha. In the desintegration stage stand volume decreased from 343 m³/ha to 258 m³/ha, volume of dead standing trees decreased from 83 m³/ha to 77 m³/ha and volume of downed trees increased from 83 m³/ha to 97 m³/ha.

3

Response of a lidar-induced fluorescence signal to yellow substance absorption [commun.]

63%

Drozdowska V. , Kowalczuk P.

Oceanologia

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1999

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tom No. 41 (4)

601-608

EN

The presence of yellow substances in seawaters was measured by the standard spectrophotometric ( in vitro) and the lidar-induced fluorescence ( in vivo) methods along a transect across the Pomeranian Bay towards the River Odra mouth, a local source of yellow substances. The experiment aimed to ascertain whether the fluorescent lidar method could be applied to yellow substance detection and whether there were any relationships and similarities in the absorption and fluorescence intensity values and their changes.

4

Analysis of temporal and spatial variability of yellow substance absorption in the southern Baltic

63%

Kowalczuk P. , Kaczmarek S.

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tom 38

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nr 1

5

Sky glint correction in measurements of upward radiance above the sea surface

63%

Olszewski J. , Kowalczuk P.

Oceanologia

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2000

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tom 42

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nr 2

EN

An experiment has been performed to determine the upward water-leaving radiance by non-contact measurement of the total upward and downward radiance above the sea surface from a moving ship. The method for achieving this aim is described: the radiance meters are both tilted in such a way that the upward radiance meter can ‘see’ that part of the measured downward radiance which would be reflected if the water surface were smooth and which is not derived directly from solar glitter. Both meters are firmly fixed in a special frame, which ensures that the required orientation is the most probable one. Time records of the measured parameters are analysed. The results are presented in several forms: frequency (histogram) analysis appears to be the most promising one.

6

Response of a lidar-induced fluorescence signal to yellow substance absorption

63%

Drozdowska V. , Kowalczuk P.

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nr 4

7

Ostatnia linia obrony : system kierowania ogniem dla baterii armat przeciwlotniczych

51%

Zawada T. , Kowalczuk P. , Kasprzak P.

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2013

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tom Vol. 54, nr 7

48-52

PL

W artykule przedstawiono koncepcję, zarys modelu i wyniki badań symulacyjnych Systemu Kierowania Ogniem (SKO) dla zastosowań w baterii armat przeciwlotniczych. System dedykowany jest bateriom OPL/OPR i wspiera przechwytywanie celów typu RAM i non-RAM. Z punktu widzenia systemów radiolokacji SKO jest agregatorem danych odbieranych z radarów aktywnych, pasywnych lub głowic optoelektronicznych. Część pierwsza artykułu stanowi wprowadzenie do problematyki śledzenia celu manewrującego. Omówiono rolę i elementy składowe SKO, klasyfikację zwalczanych celi oraz najważniejsze problemy. Następnie omówiony został model matematyczny realizujący proces estymacji i predykcji położenia, prędkości oraz przyśpieszenia śledzonego obiektu. Model bazuje na rozwinięciu koncepcji rekurencyjnego filtru Kalmana-Singera. Duży nacisk położono na implementację i analizę szumów skorelowanych stochastycznie. Kolejny rozdział zawiera zaimplementowane matematyczne modele toru lotu obiektów manewrujących. Przedyskutowano również problemy wynikające z konieczności wprowadzenia silnych nieliniowości. Druga część artykułu jest typowo badawcza - przedstawiono w niej wyniki badań symulacyjnych estymacji i predykcji obiektów manewrujących jak i niemanewrujących. Algorytm zasilony był danymi sztucznymi jak i rzeczywistymi uzyskanymi z badań poligonowych. Analizie poddano tory balistyczne celów typu RAM oraz zostały zbadane typowe manewry celów typu non-RAM. Końcową część stanowi podsumowanie omówionych problemów badawczych oraz podjęte przez zespół kierunki rozwoju system.

EN

This article presents the concept of Fire-Control System (FCS) dedicated to Air Defense gun battery, draft of the mathematical model, analysis of main problems and results from experiments. System is dedicated for AA battery and can engage RAM/non-RAM targets type. From the radiolocation systems point of view FCS act as aggregator of data acquainted from active radars, passive radars or optoelectronic tracking heads. The first part of article contains small introduction to remote, fast moving, maneuvering object tracking. We discuss components of FCS, classification of engagement targets and main problems. Next, mathematical models of estimation and prediction problem with computation of position, velocity and acceleration of targeted object are presented. As a basis we used Discrete Kalman Filter model extended with Singer model. Next part show flying path models of maneuvering objects and typical problems as a result of strong nonlinearity elements and non-stationary noises. Next, we discussed distribution of estimation and prediction errors. Problematic points like coordinate system change, singular points of flying path or tracking vector at zenith position, open-fire zones, etc. Experiments based on numerical simulations contains distributions of estimation and prediction of RAM and non-RAM objects. Durning analysis of RAM ballistic path and maneuvers of nonRAM artificial and real sensor data was used. As a conclusion we summarize presented problems, received results and draw future research directions.

8

Validation of empirical and semi-analytical remote sensing algorithms for estimating absorption by Coloured Dissolved Organic Matter in the Baltic Sea from SeaWiFS and MODIS imagery

51%

Kowalczuk P. , Darecki M. , Zablocka M. , Gorecka I.

Oceanologia

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2010

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tom 52

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nr 2

171-196

EN

An extensive bio-optical data set obtained from field measurements was used to evaluate the performance of an empirical (Kowalczuk et al. 2005) and two semi- analytical algorithms: Carder et al. (1999) and GSM01 (Maritorena et al. 2002) for estimating CDOM absorption in the Baltic Sea. The data set includes coincident measurements of radiometric quantities and absorption coefficients of CDOM made during 43 cruises between 2000 and 2008. In the first stage of the analysis, the accuracy of the empirical algorithm by Kowalczuk et al. (2005) was assessed using in situ measurements of remote sensing reflectance. Validation results improved when matching points located in Gulf of Gdańsk close to the Vistula River mouth were eliminated from the data set. The calculated errors in the estimation of aCDOM(400) in the first phase of the analysis were Bias = −0.02, RMSE = 0.46 and R2 = 0.70. In the second stage, the empirical algorithm was tested on satellite data from SeaWiFS and MODIS imagery. The satellite data were corrected atmospherically with the MUMM algorithm designed for turbid coastal and inland waters and implemented in the SeaDAS software. The results of the best case scenario for estimating the CDOM absorption coefficient aCDOM(400), based on SeaWiFS data, were Bias = −0.02, RMSE = 0.23 and R2 = 0.40. The validation of the Kowalczuk et al. (2005) empirical algorithm applied to MODIS data led to a less accurate estimate of aCDOM(400): Bias = −0.03, RMSE = 0.19 and R2 = 0.29. This assessment of the accuracy of standard semi-analytical algorithms available in the SeaWiFS and MODIS imagery processing software revealed that both algorithms (GSM 01 and Carder) underestimate CDOM absorption in the Baltic Sea with mean systematic and random errors in excess of 70%. The paper presents examples of the application of the Kowalczuk et al. (2005) empirical algorithm for producing maps of the seasonal distribution of aCDOM(400) in the Baltic Sea between 2004 and 2008.

9

In-water remote sensing algorithms for the detection of chlorophyll and yellow substances in the Pomeranian Bay

51%

Olszewski J. , Kowalczuk P. , Darecki M.

Oceanologia

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1999

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tom No. 41 (3)

461-474

EN

In-water remote sensing algorithms for estimating chlorophyll concentration and the absorption of light (400 nm) by yellow substances valid for the surface layer of the Pomeranian Bay are described. The accuracy of the algorithms has been estimated at 20-60%. The statistical analysis of data collected during a two-year experiment in 1996-1997 enable algorithms to be constructed which use a linear combination of spectral reflectances at selected wavelengths, all of them in the log-log form. The wavelengths in nm are 510, 550, 589 or 510, 625 in the 'chlorophyll' case, and 589, 665 or 490, 665 in the 'yellow substances' case. The correlation coefficient between the log-transformed reflectance ratios and the chlorophyll concentration is around 0.9. The correlation coefficient between the log-transformed reflectance ratios and the yellow substance absorption coefficient at λ= 400 nm is around 0.6.

10

Seasonal changes in selected optical parameters in the Pomeranian Bay in 1996-1997

45%

Kowalczuk P. , Sagan S. , Olszewski J. , Darecki M. , Hapter R.

Oceanologia

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1999

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tom No. 41 (3)

309-334

EN

The main task of the Joint Polish-German Pomeranian Bay Project was to achieve a better understanding of the impact of freshwater discharge on this environment. The freshwater from the River Odra enters the Pomeranian Bay through four outlets. The most important of these is the River Swina, as it carries the largest volume of water exchange between the bay and the Szczecin Lagoon. This freshwater carries a large load of optically active substances: dissolved organic materials, mineral and organic sediments, as well as nutrients, which boost phytoplankton growth. The effect of riverine discharge can be traced with the use of optical methods. The elevated level of optically active components can significantly reduce the light required for photosynthesis. The Institute of Oceanology carried out a survey of selected inherent and apparent optical properties in the Pomeranian Bay in three seasons in 1996 and 1997. The results are presented and discussed, as are the relations between the various optical parameters and salinity.

11

Wielowymiarowa analiza statystyczna wyników wzbogacania rudy miedzi w ZWR Polkowice

38%

Duchnowska M. , Kasińska-Pilut E. , Bakalarz A. , Konieczny A. , Kowalczuk P. , Łuszczkiewicz A.

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tom nr 2

97--108

PL

W pracy dokonano analizy zależności pomiędzy wzbogacaniem miedzi, srebra i węgla organicznego podczas procesu flotacji. Dokonano wielowymiarowej analizy statystycznej podstawowych wskaźników wzbogacania polkowickiej rudy miedzi w oparciu o wyniki przemysłowe flotacji za lata 2011-2015 w ZWR Polkowice. Celem pracy było wyznaczenie, oddzielnie dla każdego z ciągów technologicznych zakładu, równań, pozwalających na ocenę wzbogacania węgla organicznego w stosunku do wzbogacania miedzi i srebra. Wyznaczone równania łączą Cu, Ag i Corg, tak że na podstawie wskaźników selektywności Cu i Ag można wyznaczyć selektywność węgla organicznego, a następnie oszacować jego zawartości w produktach flotacji. Wyznaczone równania pozwalają na przewidywanie wyników wzbogacania węgla organicznego na podstawie analiz miedzi i srebra.

EN

The aim of this paper is determination of relationship between the contents of copper, silver and organic carbon in industrial flotation circuits. A multivariate statistical analysis of basic upgrading parameters’ distribution of the copper ore from the Polkowice Divisions of Concentrators on the basis of industrial results obtained between 2011 and 2015 was conducted. For each single flotation line, three equations, which connect the selectivity of copper, silver and organic carbon upgrading were determined. The obtained equations allow to calculate the upgrading selectivity and the content of Corg in the flotation products on the basis of Cu and Ag upgrading selectivities. The equations predict the results of upgrading in organic carbon basing on the data for copper and silver.

12

Kinetyka laboratoryjnej flotacji rudy miedzi z ZWR Polkowice po mieleniu w obecności mielników o różnym składzie chemicznym

32%

Bakalarz A. , Duchnowska M. , Konieczny A. , Kasińska-Pilut E. , Pawlos W. , Kaleta R. , Kowalczuk P. , Drzymała J. , Łuszczkiewicz A.

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tom nr 2

55--70

PL

Wiele danych w literaturze potwierdza, że rodzaj, skład chemiczny i ścieralność mielników użytych do przygotowania nadawy flotacyjnej wpływa na właściwości elektrochemiczne zawiesiny flotacyjnej, a tym samym na efektywność procesu wzbogacania. W pracy dokonano analizy kinetyki flotacji polkowickiej rudy miedzi mielonej w warunkach laboratoryjnych w obecności mielników stalowych (stal kuta), żeliwno-chromowych i nierdzewnych (stal łożyskowa) przy trzech różnych dawkach przemysłowego odczynnika zbierającego. Analizie poddano kinetykę flotacji miedzi, srebra, węgla organicznego oraz składników nieużytecznych, w oparciu o dostępne w literaturze modele kinetyczne. Otrzymane wyniki analiz pozwoliły na określenie charakteru kinetyki wzbogacania poszczególnych składników po procesie mielenia w różnych warunkach.

EN

Kinetics of laboratory flotation of copper ore from Polkowice Division of Concentrators after milling in the presence of grinding media with different chemical composition Abstract: Numerous data in the literature confirm that the kind, chemical composition and consumption of grinding media have an influence on the electrochemical properties of flotation suspension and the upgrading process effectiveness. The paper presents an analysis of kinetics of laboratory flotation tests of the copper ore milling in the presence of three different grinding media (forged, high-chrome and stainless) iron and three different doses of industrial collector. The analysis of flotation kinetics of copper, silver, organic carbon and remaining components content in concentrate was carried out basing on available in literature kinetics models. The results of analyses allowed to characterize the flotation kinetics of analyzed components of copper ore after milling under different conditions.