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Number of results: 20
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Abstract

During SIBEX the acoustically evaluated amount of krill in the Bransfield Strait and Drake Passage was very low with the mean density 3.24 individuals/m2 and 4.29 individuals/m2 accordingly. Any substantial quantities of krill were found North-West from the Elephant Island and North from the King George Island, where the density of krill exceeded 1000 individuals/m2 (about 100 t/nM2]). The total biomass was estimated at 70590 ton in the Bransfield Strait and at 122470 ton in the Drake Passage, which was many times less than during FIBEX 81, especially in the Bransfield Strait.

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Authors and Affiliations

Janusz Kalinowski
Małgorzata Godlewska
Zygmunt Klusek
Keywords Antarctic krill stock
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Abstract

Results from the hydro-acoustic studies aiming at evaluation of the Euphausia superba biomass in the Bransfield Strait in March 1981 are presented. These investigations, called conventionally Micro-FIBEX, were carried out on the r/v "Profesor Siedlecki" during 13-16 .March 1981, as continuation of the studies carried out in that region within the scheme of the FIBEX programme in the period of 5-12 March 1981. The abundance of the biomass was estimated at 258 thousand ton, which at the investigated area of about 1755 NM2 gives the mean value of biomass density 142 t/NM2 (41.4 g/m2).

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Authors and Affiliations

Janusz Kalinowski
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Abstract

Stocks of krill in the southern part of the Drake Passage and in the Bransfield Strait were estimated by the hydroacoustic method, during the BIOMASS-FIBEX expedition (Febr.-March 1981). Krill stocks in the Drake Passage and Bransfield Strait were assessed at about 1.2 and 2.3 mln tons, respectively. A map of krill distribution in these regions was prepared. The main krill biomass (66%) was found to occur within the Bransfield Strait which accounts for only 13.7% of the total area under survey.

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Authors and Affiliations

Janusz Kalinowski
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Abstract

Results of hydroacoustic investigations of krill biomass carried out in the South Shetland Island region between October 1986 and January 1987 are presented. A considerable difference in the krill biomass between Antarctic spring and summer was recorded. Initially observations were conducted close to Elephant Island, in the period just after the retreated of compact ice cover. Krill then aggregated only in swarms, the density of which frequently exceeded 100 t nM-2 . In the region of Polygon I (30—31 October 1986) the total estimated biomass was 26899 t, in the region of Polygon II (6—10 November 1986) it was 25827 t. Investigations were repeated in January 1987 obtaining 112372 t in the Bransfield Strait and 390309 t in the region of Elephant Island. The results are presented in tables and maps.

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Authors and Affiliations

Janusz Kalinowski
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Abstract

In this paper, we use weekly stock market data to examine whether the volatility of stock returns of ten emerging capital markets of the new EU member countries has changed since the opening of their capital markets. In particular we are interested in understanding whether there are high and low periods of stock returns volatility and what the degree of correlation across these markets is. We estimate a Markov-Switching ARCH (SWARCH) model proposed by Hamilton and Susmel (1994) and we allow for the possibility that two or three volatility regimes may exist for stock returns volatility. The main finding of the present study is that the high volatility of stock returns of all new EU emerging stock markets is associated mainly with the 1997‒1998 Asian and Russian financial crises as well as over the 2007‒2009 financial turmoil, while there is a transition to the low volatility regime as they approach the accession to the EU in 2004. It is also shown that the capital flows liberalization process has resulted in an increase in volatility of stock returns in most cases.

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Authors and Affiliations

Georgios P. Kouretas
Manolis N. Syllignakis
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Abstract

In this paper, the stock price-inflation nexus is investigated using the tools of wavelet power spectrum, cross-wavelet power spectrum and cross-wavelet coherency to unravel time and frequency dependent relationships between stock prices and inflation. Our results suggest that for a frequency band between sixteen and thirty two months, there is some evidence of the fisher effect. For rest of the frequencies and time periods however there is no evidence of the fisher effect and it seems stock prices have not played any role as an inflation hedge.

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Authors and Affiliations

Niyati Bhanja
Arif Billah Dar
Aviral Kumar Tiwari
Olaolu Richard Olayeni
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Abstract

Results of hydroacoustic investigations of krill swarms occurring southwest of Elephant Island carried out between 30 October and 5 November 1986, are presented. Krill swarms of the geometric length of 32 m, mean vertical cross section area of 206 m2 , and mean density of 133 g m-3 were recorded and measured. Biomass distribution is presented in maps. The highest density values amounting to 5001 nM-2 were recorded in the eastern part of the survey area, above the slope of Elephant Island's shelf. On the basis of upper and lower limits of the occurrence of given krill swarms, a scheme of their vertical, diurnal distribution was constructed.

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Authors and Affiliations

Janusz Kalinowski
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Abstract

Housing Stock and Its Public Dimension in the Role of Infrastructure of Durable Development. Only the reciprocal composition and location of buildings and their inhabitants in relation to the location of settlement infrastructure and other spatial development components can give housing stock a public dimension. The importance of the public impact of the housing stock on civilization development results mainly from the multifaceted role of the standards of its settlement in the shaping of inhabited space. Appreciating this impact can help build a necessary community of people living in common social and settlement structures. The importance of housing policy in balancing the development of living space is highlighted by the current structural crisis of the capitalist economy. The underestimated field of overcoming this crisis is the public dimension of housing stock. The presented reasoning subordinated to such thinking is part of a wider narrative combining architectural, urban, planning and sociological issues.
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Authors and Affiliations

Maciej Cesarski
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Abstract

It has been found that the area where one can look for significant reserves in the procurement logistics is a rational management

of the stock of raw materials. Currently, the main purpose of projects which increase the efficiency of inventory management is to

rationalise all the activities in this area, taking into account and minimising at the same time the total inventory costs. The paper presents

a method for optimising the inventory level of raw materials under a foundry plant conditions using two different control models. The first

model is based on the estimate of an optimal level of the minimum emergency stock of raw materials, giving information about the need

for an order to be placed immediately and about the optimal size of consignments ordered after the minimum emergency level has

occurred. The second model is based on the estimate of a maximum inventory level of raw materials and an optimal order cycle.

Optimisation of the presented models has been based on the previously done selection and use of rational methods for forecasting the time

series of the delivery of a chosen auxiliary material (ceramic filters) to a casting plant, including forecasting a mean size of the delivered

batch of products and its standard deviation

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Authors and Affiliations

K. Nowacki
J. Szymszal
T. Lis
J. Przondziono
J. Kliś
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Abstract

Make-To-Stock (MTS) and Make-To-Order (MTO) are the two traditional strategies in

production management. In the case of the MTS there is a growing demand for a new

approach, which is called Make-To-Availability (MTA) strategy. The paper characterizes and

compares the MTS and MTA strategies. The comparative analysis based, among others, on

computational experiments carried out in a computer program developed in Microsoft Visual

Studio 2017 Environment was presented. The models have been prepared for both strategies

with the same assumptions: external conditions (market demand) and internal conditions

(structure of the production process). The investigation of how the strategies respond to

various scenarios of demand intensity was done. The simulation models were prepared and

validated for the case of the production line in one of the industrial automation company.

The research shows that the use of the MTA strategy in the majority of cases gives much

better results than the use of the MTS strategy due to the minimization of storage costs and

the costs of non-fulfillment of the customers’ demand. The directions for further research

were also presented.

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Authors and Affiliations

Olga Ciechańska
Cezary Szwed
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Abstract

We propose a Bayesian approach to estimating productive capital stocks and depreciation rates within the production function framework, using annual data on output, employment and investment only. Productive capital stock is a concept related to the input of capital services to production, in contrast to the more common net capital stock estimates, representing market value of fixed assets. We formulate a full Bayesian model and employ it in a series of illustrative empirical examples. We find that parameters of our model, from which the time-path of capital is derived, are weakly identified with the data at hand. Nevertheless, estimation is feasible with the use of prior information on the production function parameters and the characteristics of productivity growth. We show how precision of the estimates can be improved by augmenting the model with an equation for the rate of return.
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Authors and Affiliations

Jakub Boratyński
1
Jacek Osiewalski
2

  1. University of Lodz, Lodz, Poland
  2. Cracow University of Economics, Cracow, Poland
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Abstract

The exploration of mineral resources is an area of strategic importance for the pace of further development of all industries. The results of companies deciding to carry out exploration work depend on further investments of mining companies, i.e. the entities purchasing full deposit documentation. Being at the beginning of the entire mining process, junior mines assume a high risk related to investments enabling the commencement of works without providing high guarantees of the project’s success. Companies running these types of projects must seek funding in a variety of ways. One of these is to try to raise capital from the stock trading markets. However, the specificity of junior companies does not allow them to start on the main trading floors, hence the decision to enter alternative markets. In considering the broader context of the activities of junior mines, research was conducted on companies listed on the London Alternative Investment Market (AIM). In the first part, this concerned the market characteristics – the market value added values were determined for selected ranges of market capitalization. In the second part, which is a statistical study, factors that may affect their market value was checked. The analysis covered both traditional value drivers – related to revenues, the demand for net working capital, investment expenses and the cost of equity – and their supplementation with selected values of financial statements. The result of the analysis is a regression equation indicating the factors that have a statistically significant impact on the market value of junior mines listed on AIM London.
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Authors and Affiliations

Tomasz Leśniak
1
ORCID: ORCID
Arkadiusz Jacek Kustra
1
ORCID: ORCID
Grzegorz Wilczyński
2
Rafał Tobiasz
2

  1. AGH University of Science and Technology, Kraków, Poland
  2. Bulletprove sp. z o.o., Puławy, Poland
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Abstract

Simulations are becoming one of the most important techniques supporting production preparation, even in those industrial sectors with atypical technological processes, such as in metallurgy, where there is a multiphase material flow. This is due to the fact that in the conditions of a market economy, enterprises have to solve more and more complex problems in a shorter time. On the basis of the existing production process and the knowledge of the flow characteristics in a given process, a model is built, which, when subjected to simulation tests, provides experimental results in the scope of the defined problem. The use of computer techniques also creates new possibilities for the rational use of the reserves inherent in each technological process. Taking into account the existing demand and the state of modern technology, the computer model can be a source of information for further analysis and decision-making processes supporting company management. At work a model of the logistic system was made on the example of a hot-rolled steel strip mill, on which simulation experiments were carried out to improve the effectiveness and efficiency of the analysis production line. The presented article aims to disseminate the idea of ??Industry 4.0 in Polish companies from the manufacturing industry sector, taking into account simulation techniques.
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Authors and Affiliations

Mariusz Niekurzak
1
Ewa Kubińska-Jabcoń
1

  1. AGH University of Science and Technology, Faculty of Management, Poland
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Abstract

Identification of discrete stocks of Greenland halibut is an important aspect of proper fisheries exploitation. Available literature data indicated a lack of significant inter‑area differences between Greenland halibut populations from the Northeast Atlantic. To define the population diversity, two aspects were taken into account: enzyme‑genetic diversity and the concentration of heavy metals in tissues. Seven allozyme loci variations were used to characterize the genetic structure of four populations of Greenland halibut from the Western Barents Sea region. The samples were collected from the spawning area in the period when this species took migration to spawn. The sample RH4 was significantly different from the other samples collected from the same location (RH2 and RH3) and depth for over two days. Another sample (RH8), collected from the nearby area 6 days later was similar to the samples RH2, RH3. We noticed a significant divergence between the sample RH4 and the three remaining samples, where the value of the index FST fluctuated about 0.40 and approximately 0.01 between three similar populations. This genetic fluctuation negates the thesis of a panmictic character of the Western Atlantic population. Feeding groups of Greenland halibut are moving along the Barents Sea shelf and they are exposed to different heavy metals concentrations according to the food preferences or the exact place of feeding. We identified similar concentrations of heavy metals, i.e., Zn, Cu, Cd, and Pb in all samples. Trace metal analysis of aquatic organisms from the Barents Sea can provide important information on the degree of environmental contamination, and the potential impact of seafood consumption.
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Authors and Affiliations

Barbara Wojtasik
1
Agnieszka Kijewska
2
Monika Mioduchowska
1 3
Barbara Mikuła
4
Jerzy Sell
1

  1. University of Gdansk, Department of Genetics and Biosystematics, Gdansk, Poland
  2. Institute of Oceanology, Polish Academy of Sciences, Sopot, Poland
  3. University of Gdansk, Department of Marine Plankton Research, Gdynia, Poland
  4. University of Silesia, Department of Analytical Chemistry, Faculty of Chemistry, Katowice, Poland
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Abstract

This paper describes a forecasting exercise of close-to-open returns on major global stock indices, based on high-frequency price patterns that have become available in foreign markets overnight. Generally speaking, out-of-sample forecast performance depends on the forecast method as well as the information that the forecasts are based on. In this paper both aspects are considered. The fact that the close-to-open gap is a scalar response variable to a functional variable, namely an overnight foreign price pattern, brings the prediction exercise in the realm of functional data analysis. Both parametric and non-parametric functional data analysis are considered, and compared with a simple linear benchmark model. The information set is varied by dividing global markets into three clusters, Asia-Pacific, Europe and North-America, and including or excluding price patterns on a per-cluster basis. The overall best performing forecast is nonparametric using all available information, suggesting the presence of nonlinear relations between the overnight price patterns and the opening gaps.

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Authors and Affiliations

Jan G. De Gooijer
Cees G.H. Diks
Łukasz T. Gątarek
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Abstract

The article aims to evaluate the Portuguese building stock energy policies and strategy for energy saving in buildings among the EU members. It was found out the average heat transfer coefficients of the main structural elements of Portuguese Buildings and analyzed the U-values of this elements considering different time periods.

The fundamentals of this study were funded by the Agency for Development and Innovation (ADI) and co-financed by the European Regional Development Fund (FEDER) through the Operational Program for Competitiveness Factors (POFC) assigned to the Building Physics and Construction Technology Laboratory with the reference SB Tool SPT_2011_4.

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Authors and Affiliations

J. Sousa
L. Bragança
M. Almeida
P. Silva
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Abstract

This paper presents the modeling and the resolution of a two dimensional cutting stock problem for a wooden industry. It is about a real problem of minimization of the wood wastes for an industry of furnishing. The raw material to be cut is a set of beams of various sizes. The purpose of the cut is to supply a list of orders characterized by a set of articles of various sizes. The problem is converted into an integer linear program where the decision variables are the numbers of beams to cut according to a set of feasible “patterns”. The designed solution is a heuristic in two stages: – Generation of the feasible patterns by various classic heuristics of the Bin-packing Problem. – Resolution of the integer linear program with the generated patterns as input variables. Moreover, based on this approach, the “Application Cutting Optimization” is developed to allow the immediate resolution of the problem and widening the stock management horizon. To end, a real case is studied to confirm the effectiveness of this approach.
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Authors and Affiliations

Amine Bouaine
Maria Lebbar
Mohamed Ait Ha
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Abstract

The international community affirms the critical role of forests in climate change mitigation, which includes reducing emissions from degradation and deforestation, carbon stock conservation, sustainable forest management, and increasing carbon stocks in developing countries. It relates to land use and land cover changes. This study aims to review land use and land cover changes (LULC) in two decades, namely 2000–2010 and 2010–2020, and the impact on carbon stocks. Landsat satellite imagery in 2000, 2010, and 2020 are classified into six categories: built-up area, cropland, forest, water body, bareland, and grassland. This classification uses supervised classification. The accuracy kappa coefficient values obtained for the LULC 2000, LULC 2010, and LULC 2020 maps were 89.61%, 83.90%, and 87.10%, respectively. The most dominant systematic LULC change processes were forest degradation in 2000–2020; the transition of forest to cropland (349.20 ha), forest to bareland (171.19 ha), and forest to built-up area (661.68 ha). Loss of using the forest for other uses was followed by a decrease in carbon stock. There was a high decrease in carbon stock in the forest category (11,000 Mg C∙y–1). The results showed a significant change in land use and cover. The decline in the area occurred in the forest category, which decreased from year to year. Meanwhile, the built-up area increases every year. Carbon stocks also decrease from year to year, especially forests as the most significant carbon store, decreasing in the area.
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Authors and Affiliations

Ashfa Achmad
1
ORCID: ORCID
Ichwana Ramli
2
ORCID: ORCID
Nizamuddin Nizamuddin
3
ORCID: ORCID

  1. Universitas Syiah Kuala, Architecture and Planning Department, Jl. Tgk. Syech Abdurrauf No. 7, 23111, Banda Aceh, Indonesia
  2. Universitas Syiah Kuala, Agricultural Engineering, Banda Aceh, Indonesia
  3. Universitas Syiah Kuala, Mathematics Department, Banda Aceh, Indonesia
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Abstract

The aim of the study was to recognise the accumulation of organic carbon (SOC) in the soils of Polish grasslands (GL) and to consider the possibility of increasing its sequestration in these soils. The Tiurin method (mineral soils) and the mass loss method (soil of organic origin) were used. It was found that: (i) the average SOC content of mineral soils is 2.44% and of organic soils – 10.42%; (ii) according to the Polish criteria, approximately 84% of GL mineral soils are classified as classes with high and very high SOC content, and over 15% and 1% – in classes with medium and low SOC content, respectively; more than 99% of organic soils belong to two classes with the highest SOC content and less than 1% to the class with an average content; (iii) according to the European Soil Bureau, the share of GL mineral soils with a high SOC content is slightly over 4%, medium – slightly over 47%, and low and very low – around 50%; for organic soils they are 67, 29, and 4%, respectively; (iv) the reserves of organic carbon in the 0–30 cm layer on the entire surface of GL soils amount to 412.7 Tg of SOC. There is considerable scope for increasing the SOC stock in meadow-pasture soils.
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Authors and Affiliations

Stefan Pietrzak
1
ORCID: ORCID
Jakub T. Hołaj-Krzak
1
ORCID: ORCID

  1. Institute of Technology and Life Sciences – National Research Institute, Falenty, 3 Hrabska Avenue, 05-090 Raszyn, Poland
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Abstract

Warehouse and inventory management is a recurring issue in many of the different supply chains in diverse industries, where the constant changes in the markets have a direct impact on the management of warehouses and inventories, either generating over-stocks or shortages. This paper presents a case study on warehouse and inventory management control. The company under study was having problems in this area, where over-stocks were generated frequently, leading to various incidents, such as having to store finished and packaged product in unsuitable places, with the associated risk of deterioration. To deal with this problem, control tools based on the KPI (Key Performance Indicator) concept were developed. To this end, the corresponding problem and the information management process within the Supply Chain department had to be analyzed. In this case, it was observed that the databases were not synchronized, therefore strategies were proposed to systematize the collection and updating of data. In addition, to summarize the information, we proceeded to the implementation of an interactive form that facilitates the visualization and interpretation of the evolution of the process, and to be able to apply an efficient control on it, and thus to propose corrective actions supported by evidence.
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Authors and Affiliations

Micaela Marziali
Daniel Alejandro Rossit
Adrián Toncovich

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