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Abstract

Unique and independent historical observations, carried out in the central Arctic during the early twentieth century warming (ETCW) period, were used to evaluate the older (20CRv2) and newer (20CRv2c) versions of the 20th Century Reanalysis and the HIRHAM5 regional climate model. The latter can reduce several biases compared to its forcing data set (20CRv2) probably due to higher horizontal resolution and a more realistic cloud parameterization. However, low-level temperature and near-surface specific humidity agree best between 20CRv2c and the surface-based observations. This better performance results from more realistic lower boundary conditions for sea ice concentration and sea surface temperature, but it is limited mainly to polar night. Although sea level pressures are very similar, the vertical stratification and baroclinicity change in the transition from 20CRv2 to 20CRv2c. Compared to observed temperature profiles, the systematic cold bias above 400 hPa remains almost unchanged indicating an incorrect coupling between the planetary boundary layer and free troposphere. In addition to surface pressures, it is therefore recommended to assimilate available vertical profiles of temperature, humidity and wind speed. This might also reduce the large biases in 10 m wind speed, but the reliability of the sea ice data remains a great unknown.
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Abstract

The aim of this research was to study the biodiversity of cyanobacteria and microalgae in hydro-terrestrial habitats from the area of Hornsund fjord (Svalbard archipelago). This research is particularly important, because hitherto no complex research (including all taxonomic groups) has previously been conducted on the cyanobacterial and microalgal flora in Arctic water ecosystems. The research was conducted during the summer seasons of 2011 and 2013. Shannon’s diversity index was used to describe species diversity and evenness. Data on cyanobacteria and microalgae were analyzed using the MVSP and PCA. Additionally, a basic analysis of the physicochemical properties of water in the studied ecosystems was performed. A total of 506 taxa were noted in the studied hydro-terrestrial habitats. The most numerous group was cyanobacteria, constituting 35% of all recorded taxa. Ochrophyta and Chlorphyta were almost equally numerous (percentage again as for cyanobacteria). Nineteen types of assemblages were noted in all studied hydro-terrestrial habitats. The diversity of cyanobacteria and microalgae and the assemblages formed by them were used to determine the characteristics of the studied ecosystems. Each type of water ecosystem was represented by specific phycoflora and assemblages. Ecological parameters along with biological data (the diversity of cyanobacteria and microalgae) allowed us to sort the studied hydro-terrestrial habitats by similarity. Our analyses clearly distinguished water ecosystem groups differing in species composition determining their trophic status. The research shows the usefulness of cyanobacteria and microalgae diversity defined by the Shannon-Weaver index for characterizing bodies of water and determining the trophic status of these habitats.
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Abstract

Beach pollution is one of the most common hazards in present-day anthropogenic environments. Even in the remote Svalbard Archipelago, pollution impacts the beach system and can pose environmental threats. The significant increase in human activity observed in Svalbard over the last 20–30 years has resulted in a visible change in the amount of coastal pollution. A 5 km long transect of modern beach developed along Calypsostranda (Recherchefjorden, Bellsund) was surveyed in the summer of 2015 in order to characterize the beach pollution. During the survey 296 pieces of trash were found on beach surface. 82% of found trash was plastic, followed by glass (8%), and metal (5%). The comparison with previous pollution survey showed the significant increase of plastic waste in local beach environment. Similar problem has been recently recorded in other parts of Svalbard suggesting an urgent need for coastal pollution monitoring.
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Abstract

Usnea aurantiaco-atra is the dominant flora around King George Island, Antarctica, whose specimens exhibited various phenotypes, even for those with the same ITS sequences in both mycobiont and photobiont. A comprehensive analysis of morphological traits of U. aurantiaco-atra including the reproductive structures, growth forms and ornamentation, cross section of the branches, and the substratum was carried out. Four arbitrary groups were identified based on their reproductive characters, but these groups cannot be distinguished from molecular phylogenetic trees based on fungal or algal ITS sequences. Further, the complicated morphological diversity of the thalli with the same ITS haplotypes in both mycobiont and photobiont suggest that some other factors in addition to the symbionts could influence the morphology of lichens. This implies that lichen is indeed a complex-mini-ecosystem rather than a dual symbiotic association of fungus and alga. Also, a lichenous fungi Phacopsis sp. was identified based on its anatomical characters and ITS sequence, which was also responsible for the black burls-like structures on U. aurantiaco-atra.
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Abstract

The average grades of copper mines are dropped by extracting high grade copper ores. Based on the conducted studies in the mine field, the uncertainty of economic calculations and the insufficiency of initial information is observed. This matter has drawn considerations to processing methods which not only extracts low grade copper ores but also decreases adverse environmental impacts. In this research, an optimum cut-off grades modelis developed with the objective function of Net Present Value (NPV) maximization. The costs of the processing methods are also involved in the model. In consequence, an optimization algorithm was presented to calculate and evaluate both the maximum NPV and the optimum cut-off grades. Since the selling price of the final product has always been considered as one of the major risks in the economic calculations and designing of the mines, it was included in the modeling of the price prediction algorithm. The results of the algorithm performance demonstrated that the cost of the lost opportunity and the prediction of the selling price are regarded as two main factors directed into diminishing most of the cut-off grades in the last years of the mines’ production.
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Abstract

Polish brines are highly mineralized and can potentially be used for recovery of selected useful elements such as magnesium and potassium. They also contain a number of other elements, including iodine, bromine, boron, and strontium. The results of the examination of the chemical composition of groundwater from the Mesozoic formations (bromine, iodine, lithium, magnesium, and strontium content) of northern and central Poland were analyzed. The basic statistical parameters of the content of these elements (Br, I, Mg) in brines of the Triassic, Jurassic, and Cretaceous deposits and the content of lithium and strontium in waters of the entire Mesozoic formations were determined. In order to indicate aquifers that are the most suitable for the recovery of bromine, iodine, lithium, magnesium, and strontium, the relationship between concentrations and the depth of retention and dependencies between selected chemical components of these waters were analyzed. It has been found that the mineralization and concentrations of magnesium, bromine, and iodine increase with the age of aquifers, where these waters occur. Triassic waters are the most prospective for bromine and magnesium recovery among all analyzed aquifers. Furthermore, a relationship between the content of bromine, strontium, and magnesium has also been observed. The increase in the content of individual elements observed for lithium, strontium, and bromine with the increasing depth indicates a potential abundance of waters occurring at significant depths. The presented analysis is an approximation of the content of bromine, iodine, lithium, magnesium, and strontium; however, it may be the basis for further studies on the perspectives of using brines from the Mesozoic deposits of central and northern Poland as a source of chemical raw materials.
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Abstract

Due to the fact that the landfill deposition of municipal waste with the higher heating value (HHV) than 6 MJ/kg in Poland is prohibited, the application of waste derived fuels for energy production seems to be good option. There is a new combined-heat-and-power (CHP) plant in Zabrze, where varied solid fuels can be combusted. The formation of ashes originating from the combustion of alternative fuels causes a need to find ways for their practical application and demands the knowledge about their properties. Therefore, the present work is devoted to studying the co-combustion of solid recovered fuel (SRF) and coal, its impact on fly ash quality and the potential application of ashes to synthesis zeolites. The major objectives of this paper is to present the detail characteristics of ash generated during this process by using the advanced instrumental techniques (XRF, XRD, SEM, B ET, TGA). The co-combustion were carried out at 0.1 MWth fluidized bed combustor. The amount of SRF in fuel mixture was 1, 5, 10 and 20%, respectively. The focus is on the comparison the ashes depending on the fuel mixture composition. Generally, the ashes characterise high amounts of SiO2, Al2O3 and Fe2O3. It is well observed, that the chemical composition of ashes from co-combustion of blends reflects the amount of SRF addition. Considering the chemical composition of studied ashes, they can be utilize as a zeolites A. The main conclusions is that SRF can be successfully combusted with coal in CFB technology and the fly ashes obtained from coal + SRF fuel mixtures can be used to synthesis zeolites.
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Abstract

The optimization of cut-off grades is a fundamental issue for metallic ore deposits. The cut-off grade is used to classify the material as ore or waste. Due to the time value of money, in order to achieve the maximum net present value, an optimum schedules of cut-off grades must be used. The depletion rate is the rate of depletion of a mineral deposit. Variable mining costs are to be applied to the really excavated material, as some of the depletion can be left in-situ. Due to access constraints, some of the blocks that have an average grade less than the determined cut-off grade are left in-situ, some of them are excavated and dumped as waste material. Naturally, variable mining costs should be applied to the blocks of a mineral deposit that are actually excavated. The probability density function of an exponential distribution is used to find the portion of the depletion rate over the production rate that is to be left in-situ. As a result, inverse probability density function is to be applied as the portion of the depletion rate over the production rate that is to be excavated and dumped. The parts of a mineral deposit that are excavated but will be dumped as waste material incur some additional cost of rehabilitation that is to be included in the algorithm of the cut-off grades optimization. This paper describes the general problem of cut-off grades optimization and outlines the further extension of the method including various depletion rates and variable rehabilitation cost. The author introduces the general background of the use of grid search in cut-off grades optimization by using various depletion rates and variable rehabilitation cost. The software developed in this subject is checked by means of a case study.
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Abstract

Planning in a mining enterprise is a complex and multifaceted action. For this reason, it is necessary to provide its proper organisation and adjust it to the specific conditions of conducting underground mining extraction. The prepared plans must make up a cohesive internal system, unambiguously determining the manner, range and safety requirements of the conducted extraction. In the most general manner, the various types of plans developed by organisational units of mining enterprises can be divided based on the timeframe, type, scope and object of planning. These are strategic plans, tactical plans and subject-based plans. The aim of the article is to present the issue of production planning in a mining enterprise and for the preparation of such a plan, first and foremost, information about, among other things, applicable legal regulations, market conditions and the specificity of a mining enterprise are necessary. Underground extraction of black coal deposits must be conducted while respecting the rules of sustainable development which satisfies current needs, without compromising the ability to satisfy the needs of future generations. Due to the specific nature of mining production, manifested, among other things, by such features as the diversity of conditions for conducting the activity, resulting from the changing geological-mining conditions of the deposit, low flexibility of the production process, associated with the impossibility to conduct alternative production and a very long-lasting investment process, planning the course and magnitude of production in a mining enterprise must proceed with the highest possible diligence. One should take into account a wide range of presented environmental, organisational and technical conditions, deciding about the safety and correctness of the course of the assumed production activities. However, in order to make them economically feasible and produce satisfying results in that regard, it is also necessary to analyse them carefully with respect to financial outcomes
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Abstract

Automatic gender detection is a process of determining the gender of a human according to the characteristic properties that represent the masculine and feminine attributes of a subject. Automatic gender detection is used in many areas such as customer behaviour analysis, robust security system construction, resource management, human-computer interaction, video games, mobile applications, neuro-marketing etc., in which manual gender detection may be not feasible. In this study, we have developed a fully automatic system that uses the 3D anthropometric measurements of human subjects for gender detection. A Kinect 3D camera was used to recognize the human posture, and body metrics are used as features for classification. To classify the gender, KNN, SVM classifiers and Neural Network were used with the parameters. A unique dataset gathered from 29 female and 31 male (a total of 60 people) participants was used in the experiment and the Leave One Out method was used as the cross-validation approach. The maximum accuracy achieved is 96.77% for SVM with an MLP kernel function.
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Abstract

Problems associated with designing silencers are presented. Results of direct tests of silencers for cooperation with systems of axial fans, as well as results of numerical tests of a two stage acoustic silencer, are given. The numerical tests enabled determining the distribution of acoustic field inside the silencer and in the surrounding area. In those tests A sound insertion losses for different variants of installation inside the silencer, as well as for two different types of absorbing material used to fill the silencer walls, were determined. Impact of design features of silencers on effectiveness of noise reduction is described. Also, a technical sketch of a universal silencer with significant noise reduction (DipS = 39:1 dB) which can be successfully used in many ventilation systems is presented
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Abstract

Micro perforated panel (MPP) absorber is a new form of acoustic absorbing material in comparison with porous ones. These absorbers are considered as next generation ones and the best alternative for traditional porous materials like foams. MPP combined with a uniform air gap constructs an absorber which has high absorption but in a narrow bandwidth of frequency. This characteristic makes MPPAs insufficient for practical purposes in comparison with porous materials. In this study instead of using a uniform air gap behind the MPP, the cavity is divided into several partitions with different depth arrangement which have parallel faces. This method improves the absorption bandwidth to reach the looked for goal. To achieve theoretical absorption of this absorber, equivalent electro-acoustic circuit and Maa’s theory (Maa, 1998) are employed. Maa suggested formulas to calculate MPP’s impedance which show good match with experimental results carried out in previous studies. Electro-acoustic analogy is used to combine MPP’s impedance with acoustic impedances of complex partitioned cavity. To verify the theoretical analyses, constructed samples are experimentally tested via impedance tube. To establish the test, a multi-depth setup facing a MPP is inserted into impedance tube and the absorption coefficient is examined in the 63–1600 Hz frequency range. Theoretical results show good agreement compared to measured data, by which a conclusion can be made that partitioning the cavity behind MPP into different depths will improve absorption bandwidth and the electro-acoustic analogy is an appropriate theoretical method for absorption enhancement research, although an optimisation process is needed to achieve best results to prove the capability of this absorber. The optimisation process provides maximum possible absorption in a desired frequency range for a specified cavity configuration by giving the proper cavity depths. In this article numerical optimisation has been done to find cavity depths for a unique MPP.
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Abstract

Natural sounds are essential elements for ecosystems, and therefore necessary for many ecological functions, forming what is called “natural soundscapes”. The Natural Reserve Laguna del Portil (NRLP), located in the southwest of the Iberian Peninsula, is an ecosystem which was declared by Spanish authorities as Protected Natural Reserve. In the south area of the NRLP, there is a regional road with high traffic intensity, which affects the soundscapes of this natural reserve. In this study, the road potential noise impact on the natural sounds of the NLRP is analysed. This analysis was done both in winter and summer, and also using two independent methods: 1) spatial sampling measures in 43 different points of the NRL; and 2) noise mapping using noise levels prediction software. From the comparison of the results of both methods and seasons the following conclusions were reached: 1) an approach to the natural soundscape of NRLP both in winter and summer, 2) the acoustic impact of the road on the NRLP, and 3) the variation of the traffic noise depending on the distance to the road, and its seasonal variation. This study could be to improve the management of the NRLP and to help to preserve the natural soundscape of the reserve.
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Abstract

Surface Acoustic Wave (SAW) devices like delay lines, filters, resonators etc., are nowadays extensively used as principal solid state components in many electronic applications and chemical vapour sensors. To bring out the best from these SAW devices, computational design and modelling are resorted too. The present paper proposes the modelling of 400 MHz ST-X Quartz based SAW delay line, by three models namely, Impulse Response Model (IRM), Crossed-field Equivalent Circuit Model (ECM) and Couplingof- Modes (COM) model. MATLABr is employed as a computational tool to model the experimental output of the SAW device. A comparative discussion of the modelled device results is also provided.
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Abstract

The church of Santa Cruz de Oleiros, Spain (1967) shows architect Miguel Fisac’s perception of sacred space after the Second Vatican Council. In this place of worship, the architect responded to the new liturgical guidelines combining geometry and architectural forms with the material of the moment, concrete. However, ordinary religious celebrations reveal acoustic deficiencies for the main use of the building. This fact is corroborated by acoustic measurements in situ. With a methodology that uses simulation techniques for the sound field, the analysis of the current acoustic behaviour of the room will serve as the basis for an acoustic rehabilitation proposal aimed at improving the acoustic conditions and so, the functionality of the church.
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Abstract

In this paper an alternative procedure to vibro-acoustics study of beam-type structures is presented. With this procedure, it is possible to determine the resonant modes, the bending wave propagation velocity through the study of the radiated acoustic field and their temporal evolution in the frequency range selected. As regards the purely experimental aspect, it is worth noting that the exciter device is an actuator similar to is the one employed in distributed modes loudspeakers; the test signal used is a pseudo random sequence, in particular, an MLS (Maximum Length Sequence), facilitates post processing. The study case was applied to two beam-type structures made of a sandstone material called Bateig. The experimental results of the modal response and the bending propagation velocity are compared with well-established analytical solution: Euler-Bernoulli and Timoshenko models, and numerical models: Finite Element Method – FEM, showing a good agreement.
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Abstract

This paper proposes an active noise control (ANC) application to attenuate siren noise for the patient lying inside ambulance with no sound proofing. From the point of cost effectiveness, a local ANC system based on feedforward scheme is considered. Further, to handle the limitation of limited Zone of Silence (ZoS), the ANC based on virtual sensing is explored. The simulations are done in MATLAB for the recorded ambulance siren noise signal. The results indicate that ANC can be an effective solution for creating a silent environment for the patient.
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Abstract

The shipping noise near channels and ports is an important contribution to the ambient noise level, and the depth of these sites is often less than 100 m. However less attention has been paid to the measurement in shallow water environments (Brooker, Humphrey, 2016). This paper presents extensive measurements made on the URN (underwater radiated noise) of a small fishing boat in the South China Sea with 87 m depth. The URN data showed that the noise below 30 Hz was dominated by the background noise. The transmission loss (TL) was modelled with FEM (finite element method) and ray tracing according to the realistic environmental parameters in situ. The discrepancy between the modelled results and the results using simple law demonstrates both sea surface and bottom have significant effect on TL for the shallow water, especially at low frequencies. Inspired by the modelling methodology in AQUO (Achieve QUieter Oceans) project (Audoly et al., 2015), a predicted model applied to a typical fishing boat was built, which showed that the URN at frequencies below and above 100 Hz was dominated by non-cavitation propeller noise and mechanical noise, respectively. The agreement between predicted results and measured results also demonstrates that this modelling methodology is effective to some extent.
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Abstract

Speech emotion recognition is an important part of human-machine interaction studies. The acoustic analysis method is used for emotion recognition through speech. An emotion does not cause changes on all acoustic parameters. Rather, the acoustic parameters affected by emotion vary depending on the emotion type. In this context, the emotion-based variability of acoustic parameters is still a current field of study. The purpose of this study is to investigate the acoustic parameters that fear affects and the extent of their influence. For this purpose, various acoustic parameters were obtained from speech records containing fear and neutral emotions. The change according to the emotional states of these parameters was analyzed using statistical methods, and the parameters and the degree of influence that the fear emotion affected were determined. According to the results obtained, the majority of acoustic parameters that fear affects vary according to the used data. However, it has been demonstrated that formant frequencies, mel-frequency cepstral coefficients, and jitter parameters can define the fear emotion independent of the data used.
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Abstract

A new method for determining optimum dimension ratios for small rectangular rooms has been presented. In a theoretical model, an exact description of the room impulse response was used. Based on the impulse response, a frequency response of a room was calculated to find changes in the sound pressure level over the frequency range 20–200 Hz. These changes depend on the source and receiver positions, thus, a new metric equivalent to an average frequency response was introduced to quantify the overall sound pressure variation within the room for a selected source position. A numerical procedure was employed to seek a minimum value of the deviation of the sound pressure level response from a smooth fitted response determined by the quadratic polynomial regression. The most smooth frequency responses were obtained when the source was located at one of the eight corners of a room. Thus, to find the best possible dimension ratios, in the numerical procedure the optimal source position was assumed. Calculation results have shown that optimum dimension ratios depend on the room volume and the sound damping inside a room, and for small and medium volumes these ratios are roughly 1 : 1.48 : 2.12, 1 : 1.4 : 1.89 and 1 : 1.2 : 1.45. When the room volume was suitably large, the ratio 1 : 1.2 : 1.44 was found to be the best one.
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Abstract

Noise spectroscopy as a highly sensitive method for non-destructive diagnostics of semiconductor devices was applied to solar cells based on crystalline silicon with a view to evaluating the quality and reliability of this solar cell type. The experimental approach was used in a reverse-biased condition where the internal structure of solar cells, as well as pn-junction itself, was electrically stressed and overloaded by a strong electric field. This gave rise to a strong generation of a current noise accompanied by local thermal instabilities, especially in the defect sites. It turned out that local temperature changes could be correlated with generation of flicker noise in a wide frequency range. Furthermore, an electrical breakdown in a nonstable form also occurred in some specific local regions what created micro-plasma noise with a two-level current fluctuation in the form of a Lorentzian-like noise spectrum. The noise research was carried out on both of these phenomena in combination with the spectrally-filtered electroluminescence mapping in the visible/near-infrared spectrum range and the dark lock-in infrared thermography in the far-infrared range. Then the physical origin of the light emission from particular defects was searched by a scanning electron microscope and additionally there was performed an experimental elimination of one specific defect by the focused ion beam milling.
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Abstract

The void fraction is one of the most important parameters characterizing a multiphase flow. The prediction of the performance of any system operating with more than single phase relies on our knowledge and ability to measure the void fraction. In this work, a validated simulation study was performed in order to predict the void fraction independent of the flow pattern in gas-liquid two-phase flows using a gamma ray 60Co source and just one scintillation detector with the help of an artificial neural network (ANN) model of radial basis function (RBF). Three used inputs of ANN include a registered count under Compton continuum and counts under full energy peaks of 1173 and 1333 keV. The output is a void fraction percentage. Applying this methodology, the percentage of void fraction independent of the flow pattern of a gas-liquid two-phase flow was estimated with a mean relative error less than 1.17%. Although the error obtained in this study is almost close to those obtained in other similar works, only one detector was used, while in the previous studies at least two detectors were employed. Advantages of using fewer detectors are: cost reduction and system simplification.
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Abstract

In this paper, two new sinusoidal signal frequency estimators calculated on the basis of four equally spaced signal samples are presented. These estimators are called four-point estimators. Simulation and experimental research consisting in signal frequency estimation using the invented estimators have been carried out. Simulation has also been performed for frequency tracking. The simulation research was carried out applying the MathCAD computer program that determined samples of a sinusoidal signal disturbed by Gaussian noise. In the experimental research, sinusoidal signal samples were obtained by means of a National Instruments PCI-6024E data acquisition card and an Agilent 33220A function generator. On the basis of the collected samples, the values of four-point estimators invented by the authors and, for comparison, the values of three- and four-point estimators proposed by Vizireanu were determined. Next, estimation errors of the signal frequency were determined. It has been shown that the invented estimators can estimate a signal frequency with greater accuracy.
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Abstract

Due to the difficulty of detecting traces of organic acid mixture in an aqueous sample and the complexity of resolving UV-Vis spectra effectively, a combinatory method based on a self-made radical electric focusing solid phase extraction (REFSPE) device, UV-Vis detection and partial least squares (PLS) calculation is proposed here. In this study, REFSPE was used to enhance the extraction process of analytes between the aqueous phase and the membrane phase to enrich the trace of mixed organic acid efficiently. Then, the analytes, which were eluted from the adsorption film by ethanol with the assistance of an ultrasonic cleaning machine, were detected with UV-Vis spectrophotometry. After that, the PLS method was introduced to solve the problem of overlapping peaks in UV-Vis spectra of mixed substances and to quantify each compound. The linearly dependent coefficients between the predicted value of the model and the actual concentration of the sample were all higher than 0.99. The limit values of detection for benzoic acid, phthalic acid and p-toluene sulfonic acid were found at 9.9 #22;g/L, 12.2 #22;g/L and 13.8 #22;g/L with the relative recovery values between 84.8% and 117.9%. The RSD (n = 20) values of each component are 1.17%, 1.11% and 0.86%, respectively. Therefore, the proposed combined method can determine traces of complex materials in an aqueous sample efficiently and has wonderful potential applications.
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