bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk Factors for Plantar Foot Ulcer Recurrence in Neuropathic Diabetic Patients
Authors: Waaijman Roelof , de Haart Mirjam , Arts Mark L.J. , Wever Daniel , Verlouw Anke J.W.E. , Nollet Frans , Bus Sicco A.
Published: April 2014

OBJECTIVE

Recurrence of plantar foot ulcers is a common and major problem in diabetes but not well understood. Foot biomechanics and patient behavior may be important. The aim was to identify risk factors for ulcer recurrence and to establish targets for ulcer prevention.

RESEARCH DESIGN AND METHODS

As part of a footwear trial, 171 neuropathic diabetic patients with a recently healed plantar foot ulcer and custom-made footwear were followed for 18 months or until ulceration. Demographic data, disease-related parameters, presence of minor lesions, barefoot and in-shoe plantar peak pressures, footwear adherence, and daily stride count were entered in a multivariate multilevel logistic regression model of plantar foot ulcer recurrence.

RESULTS

A total of 71 patients had a recurrent ulcer. Significant independent predictors were presence of minor lesions (odds ratio 9.06 [95% CI 2.98–27.57]), day-to-day variation in stride count (0.93 [0.89–0.99]), and cumulative duration of past foot ulcers (1.03 [1.00–1.06]). Significant independent predictors for those 41 recurrences suggested to be the result of unrecognized repetitive trauma were presence of minor lesions (10.95 [5.01–23.96]), in-shoe peak pressure <200 kPa with footwear adherence >80% (0.43 [0.20–0.94]), barefoot peak pressure (1.11 [1.00–1.22]), and day-to-day variation in stride count (0.91 [0.86–0.96]).

CONCLUSIONS

The presence of a minor lesion was clearly the strongest predictor, while recommended use of adequately offloading footwear was a strong protector against ulcer recurrence from unrecognized repetitive trauma. These outcomes define clear targets for diabetic foot screening and ulcer prevention.
Clinical Outcomes and Cost-effectiveness of Continuous Positive Airway Pressure to Manage Obstructive Sleep Apnea in Patients With Type 2 Diabetes in the U.K.
Authors: Guest Julian F. , Panca Monica , Sladkevicius Erikas , Taheri Shahrad , Stradling John
Published: April 2014

OBJECTIVE

To assess clinical outcomes and cost-effectiveness of using continuous positive airway pressure (CPAP) to manage obstructive sleep apnea (OSA) in patients with type 2 diabetes (T2D) from the perspective of the U.K.’s National Health Service (NHS).

RESEARCH DESIGN AND METHODS

Using a case-control design, 150 CPAP-treated patients with OSA and T2D were randomly selected from The Health Improvement Network (THIN) database (a nationally representative database of patients registered with general practitioners in the U.K.) and matched with 150 OSA and T2D patients from the same database who were not treated with CPAP. The total NHS cost and outcomes of patient management in both groups over 5 years and the cost-effectiveness of CPAP compared with no CPAP treatment were estimated.

RESULTS

Using CPAP was associated with significantly lower blood pressure at 5 years and increasingly lower HbA1c levels over 5 consecutive years compared with untreated OSA patients. At 5 years, the HbA1c level in the CPAP-treated group was 8.2% (66.0 mmol/mol) vs. 12.1% (108.4 mmol/mol) in the control group (P < 0.03). Use of CPAP significantly increased patients’ health status by 0.27 quality-adjusted life years (QALYs) per patient over 5 years (P < 0.001) and NHS management costs by £4,141 per patient over 5 years; the cost per QALY gained with CPAP was £15,337.

CONCLUSIONS

Initiating treatment with CPAP in OSA patients with T2D leads to significantly lower blood pressure and better controlled diabetes and affords a cost-effective use of NHS resources. These observations have the potential for treatment modification if confirmed in a prospective study.
Cumhuriyet Üniversitesi Hastanesi’nde 2007-2012 döneminde diyabetik ayağa bağlı operasyon olan hastaların özellikleri ile yaş ve cinsiyetin diyabetik ayak operasyonlarını tahmin ettirici etkisi
Authors: Kalpakçı Pınar , Sezer Recep Erol , Yılmaz Sarper , Öztürk Hayati , Erturhan Selam
Published: April 2014

Amaç: Sivas Cumhuriyet Üniversitesi Hastanesi’nde ampütasyon ve debridman operasyonları yapılan hastaların özelliklerinin tanımlanması ve bu özelliklerden yaş ve cinsiyetin operasyona neden olma riskinin tahminidir.Yöntem: Çalışma için Ocak 2007-Mart 2012 tarihleri arasında Cumhuriyet Üniversitesi Tıp Fakültesi Hastanesi ‘Ortopedi ve Travmatoloji’ ve ‘Plastik ve Rekonstrüktif Cerrahi’ Anabilim Dalları’nda diyabetik ayak sonucu yapılan tüm ampütasyon ve debridman operasyonları retrospektif olarak tarandı, toplam olgu sayısı 144 idi. Diyabette yaş ve cinsiyetin diyabetik ayağa bağlı operasyonlara yol açma riskini hesaplayabilmek için 2008’de yapılmış Sivas diyabet prevalansı toplum taramasının diyabetikleri kontrol grubu (n=237) olarak seçildi. Diyabetiklerde yaş ve cinsiyetin diyabetik ayak operasyonlarıyla ilişkisini araştırmak üzere çoklu lojistik regresyon analizi tekniğini kullandık.Bulgular: 2008-2011 döneminde yıllık operasyon sayısı ortalama 27.4 dür. Lojistik regresyonla yapılan analiz sonucu diyabetik ayağa bağlı operasyon riski yaşa göre düzeltilmiş (adjusted) odds oranı ve buna ait %95 güven sınırları; erkeklerde kadınlara göre 4,5 (2,78- 7,58) olarak tahmin edilmiştir (p
Kinetics of the σ Phase Precipitation in Respect of Erosion-corrosion Wear of Duplex Cast Steel
Authors: Brodziak-Hyska A. , Stradomski Z. , Kolan C.
Published: April 2014

The examined material comprised two grades of corrosion-resistant cast steel, namely GX2CrNiMoN25-6-3 and GX2CrNiMoCuN25-6-3- 3, used for example in elements of systems of wet flue gas desulphurisation in power industry. The operating conditions in media heated up to 70°C and containing Cl' and SO4 ions and solid particles produce high erosive and corrosive wear.The work proposes an application of the σ phase as a component of precipitation strengthening mechanism in order to increase the functional properties of the material. The paper presents the results of examination of the kinetics of σ phase precipitation at a temperature of 800°C and at times ranging from 30 to 180 minutes. Changes in the morphology of precipitates of the σ phase were determined using the value of shape factor R. Resistance to erosion-corrosion wear of duplex cast steel was correlated with the kinetics of sigma phase precipitating.
The Initial Assessment of Effectiveness of the Impulse Method of Introducing an Inoculant into Cast Iron
Authors: Derda-Ślęzak A. , Soiński M.S.
Published: April 2014

An initial assessment of the effectiveness of cast iron inoculation, performed by the method of impulse introducing the master alloy into cast iron, is presented. The experiment was concerned with the hypoeutectic gray cast iron inoculated with either the Alinoc or the Barinoc master alloy by means of an experimental device for pneumatic transportation. Examinations involved pneumatic injection of the powdered inoculant carried in a stream of gaseous medium (argon) into the metal bath held in the crucible of an induction furnace. It was found that the examined process is characterised by both high effectiveness and stability.
Investment Casting vs Replicast CS Considered in Terms of the Ceramic Mould Making and Dimensional Accuracy of Castings
Authors: Karwiński A. , Haratym R. , Biernacki R. , Soroczyński A.
Published: April 2014

The article presents an analysis of the applicability of the Replicast CS process as an alternative to the investment casting process, considered in terms of the dimensional accuracy of castings. Ceramic shell moulds were based on the Ekosil binder and a wide range of ceramic materials, such as crystalline quartz, fused silica, aluminosilicates and zirconium silicate. The linear dimensions were measured with a Zeiss UMC 550 machine that allowed reducing to minimum the measurement uncertainty
The Abrasive Wear Resistance of Chromium Cast Iron
Authors: Kopyciński D. , Piasny S. , Kawalec M. , Madizhanova A.
Published: April 2014

The resistance of cast iron to abrasive wear depends on the metal abrasive hardness ratio. For example, hardness of the structural constituents of the cast iron metal matrix is lower than the hardness of ordinary silica sand. Also cementite, the basic component of unalloyed white cast iron, has hardness lower than the hardness of silica. Some resistance to the abrasive effect of the aforementioned silica sand can provide the chromium white cast iron containing in its structure a large amount of (Cr, Fe)7C3 carbides characterised by hardness higher than the hardness of the silica sand in question. In the present study, it has been anticipated that the white cast iron structure will be changed by changing the type of metal matrix and the type of carbides present in this matrix, which will greatly expand the application area of castings under the harsh operating conditions of abrasive wear. Moreover, the study compares the results of abrasive wear resistance tests performed on the examined types of cast iron. Tests of abrasive wear resistance were carried out on a Miller machine. Samples of standard dimensions were exposed to abrasion in a double to-and-fro movement, sliding against the bottom of a trough filled with an aqueous abrasive mixture containing SiC + distilled water. The obtained results of changes in the sample weight were approximated with a power curve and shown further in the study.
Characterization of Coatings on Grey Cast Iron Fabricated by Hot-dipping in Pure Al, AlSi11 and AlTi5 Alloys
Authors: Mola R. , Bucki T. , Wcisło K.
Published: April 2014

Flake graphite cast iron was hot-dip coated with pure aluminium or aluminium alloys (AlSi11 and AlTi5). The study aimed at determining the influence of bath composition on the thickness, microstructure and phase composition of the coatings. The analysis was conducted by means of an optical microscope and a scanning electron microscope with an EDS spectrometer. It was found that the overall thickness of a coating was greatly dependent on the chemical composition of a bath. The coatings consisted of an outer layer and an inner intermetallic layer, the latter with two zones and dispersed graphite. In all the cases considered, the zone in the inner intermetallic layer adjacent to the cast iron substrate contained the Al5Fe2 phase with small amount of silicon; the interface between this phase and the cast iron substrate differed substantially, depending on the bath composition. In the coatings produced by hot-dipping in pure aluminium the zone adjacent to the outer layer had a composition similar to that produced from an AlTi5 bath, the Al3Fe phase was identified in this zone. The Al3Fe also contained silicon but its amount was lower than that in the Al5Fe2. In the coatings produced by hot-dipping in AlSi11, the zone adjacent to the outer layer contained the Al3FeSi phase. The analysis results showed that when AlSi11 alloy was applied, the growth mode of the inner layer changed from inwards to outwards. The interface between the Al5Fe2 phase and the cast iron substrate was flat and the zone of this phase was very thin. Locally, there were deep penetrations of the Al5FeSi phase into the outer layer, and the interface between this phase and the outer layer was irregular. Immersion in an AlTi5 bath caused that the inner intermetallic layer was thicker than when pure aluminium or AlSi11 alloy baths were used; also, some porosity was observed in this layer; and finally, the interface between the inner layer and the cast iron substrate was the most irregular
Analysis of Densification Process and Structure of PM Al-Mg-Si-Cu-Fe and Al-Zn-Mg-Cu-Sn Alloys
Authors: Bidulský R. , Bidulská J. , Grande M. Actis
Published: April 2014

The paper is focused on the role of the pressing pressure on the densification behaviour of PM aluminium alloys. Commercially aluminium based powders Al-Mg-Si-Cu-Fe and Al-Zn-Mg-Cu-Sn were used as materials to be investigated. The apparent density of the powder mixes was determined according to MPIF St. 04. A set of cylinder test specimen 55x10x10 mm3 was uniaxially pressed in a floating hardened steel die. Compaction pressures ranged from 50 MPa up to 700 MPa. Considering the densification of metal powders in uniaxial compaction, quantification of aluminium compaction behaviour was performed. The compressibility behaviour was evaluated, considering the effect on specimens, as well as on their microstructure. The development of compressibility values with pressing pressure enables to characterize the effect of particles geometry and matrix plasticity on the compaction process.
The Morphology of the Alumina Films Formed tn The Anodization Process of Aluminium in the Orthophosphoric Acid Solution. The Co-Fe Alloys Electrodeposition Into Obtained Alumina Pores
Authors: Gumowska W. , Dobosz I. , Wrzoszczyk B.
Published: April 2014

The optimal parameters of the anodic oxidation of aluminium in orthophosphoric acid solution was determined. In the pores of the obtained Al2O3 membranes with the ordered nanometric structure Co-Fe alloys were electrodeposited. The Al2O3 membranes were obtained in the two-stage anodic oxidation of aluminium in the 0.17 M H3PO4 solution in the temperature 1°C and at the electrolysis voltage 180 V. The influence of the anodizing process parameters on the thickness of oxide films and the diameter of pores and the distance between them in the alumina membranes were determined.

The electrodeposition of Co-Fe alloys was carried out from sulphate baths containing sulphates (VI) of copper (II) and cobalt (II) of different composition, in potentiostatic conditions. The optimal electrolysis conditions were determined, where the cathodic deposits of the best quality were obtained. The conditions are: the electrolyte composition: 0.3 M Fe; 0.5 M Co; pH = 3, the potential: -0.760 V (vs. SHE1)).
Modeling Physicochemical Properties of Mold Slag
Authors: Kalisz D.
Published: April 2014

This paper deals with the mathematical modeling of physicochemical properties of mold slag such as: viscosity, surface tension, temperature liquidus, basicity. Computer simulation of slag viscosity was made by the Nakamoto structural model. The effect of addition CaF2 to the mold slag was estimated by using of Urbain model. The results were compared with the results of the experiment. Surface tension for the basic slag composition: CaO - SiO2 - Al2O3 was calculated with using Nakamoto model. The results of calculations indicate that the content of the SiO2 lowers the surface tension, but increase the content of CaO and Al2O3 in the slag increases its value. Calcium fluoride (CaF2) reduces the viscosity of the slag. The increase in temperature reduces the viscosity of the slag, simultaneously increasing the surface tension.
The Influence Of Potential-Current Conditions on the Electrodeposition of Ni-Sn Alloys from Acidic Chloride-Sulphate Solution
Authors: Rudnik E. , Włoch G. , Czernecka A.
Published: April 2014

Ni - Sn alloys were electrodeposited from acidic chloride-sulphate solution in potentiostatic and galvanostatic conditions. Cyclic voltammetry and Hull cell were used for the selection of the appropriate deposition potentials and cathodic current densities, respectively. In the potentiostatic conditions (-1.0 - -1.2 V vs. Ag/AgCl) porous deposits (~7-10 wt% Ni) were obtained, while dense coatings (~15-34 wt% Ni) were produced in the galvanostatic conditions (0.5-1.5 A/dm2). In both cases, deposits consisted of β - Sn and Ni3Sn4 phases. Speciation of the bath was also calculated.
A New Microwave Ceramic – Polymer Composite with 0-3 Connectivity
Authors: Czekaj D. , Micior J. , Lisińska-Czekaj A.
Published: April 2014

Goal of the present research was to fabricate and study two-phase BiNbO4//PVDF composites with 0-3 connectivity. Such composite consists of there-dimensionally connected polymer matrix loaded with dielectric ceramic particles. In the present case BiNbO4 powder acted as an active phase (dispersed phase) whereas polyvinylidene fluoride (PVDF) acted as a non-active (passive) phase (matrix). BiNbO4//PVDF composites with the volume fraction of the ceramic phase cν =2, 4, 6, 8, 10, 16 and 20 vol. % were prepared. Average grain size of BiNbO4 powder was =1.86 μm. It was found that BiNbO4 powder exhibited orthorhombic symmetry with Pnna (52) space group and PVDF polymer powder was α-phase. Minimum of dielectric losses at room temperature were found within the frequency range Δν =103-104 Hz. It was found that composite with cν =10% of ceramic powder exhibited lower values of dielectric permittivity.
Application Examples for the Different Measurement Modes of Electrical Properties of the Solar Cells
Authors: Musztyfaga-Staszuk M. , Dobrzanski L.A. , Rusz S. , Staszuk M.
Published: April 2014

The aim of the paper was to apply the newly developed instruments ‘Corescan’ and ‘Sherescan’ in order to measure the essential parameters of producing solar cells in comparison with the standard techniques. The standard technique named the Transmission Line Method (TLM) is one way to monitor contacting process to measure contact resistance locally between the substrate and metallization. Nowadays, contact resistance is measured over the whole photovoltaic cell using Corescanner instrument. The Sherescan device in comparison with standard devices gives a possibility to measure the sheet resistance of the emitter of silicon wafers and determine of both P/N recognition and metal resistance. The Screen Printing (SP) method is the most widely used contact formation technique for commercial silicon solar cells. The contact resistance of manufactured front metallization depends of both the paste composition and co-firing conditions. Screen printed front side metallization and next to co-fired in the infrared conveyor furnace was carried out at various temperature from 770°C to 920°C. The silver paste used in the present paper is commercial. The investigations were carried out on monocrystalline silicon wafers. The topography of co-fired in the infrared belt furnace front metallization was investigated using the atomic force microscope and scanning electron microscope (SEM). There were researched also cross sections of front contacts using SEM microscope. Front contacts of the solar cells were formed on non-textured silicon surface with coated antireflection layer. On one hand, based on electrical properties investigations using Sherescan instrument it was obtained the knowledge of the emitter sheet resistance across the surface of a wafer, what is essential in optimizing the emitter diffusion process. On the other hand, it was found using Corescan instrument that the higher temperature apparently results in a strongly decreased contact resistance.
The Structural Stability of the Fe36Co36Si19B5Nb4 Bulk Amorphous Alloy
Authors: Nabiałek M. , Pietrusiewicz P. , Szota M. , Dobrzanska-Danikiewicz A. , Lesz S. , Dospiał M. , Błoch K. , Ozga K.
Published: April 2014

In this paper, the results of the investigation into the fractured surface microstructure of the amorphous samples of Fe36Co36B19Si5Nb4 in the shape of rods of diameters: 1 mm, 2 mm and 3 mm in the as-cast state are presented. The samples were prepared by injection of molten alloy into cooled copper dies. The process of diffusion in the investigated material has a different speed depending on the temperature gradient within the volume of the rod. The atomic diffusion leads to the creation of different zones within the rod fracture: the zone in contact with the copper die, the intermediate fracture zone, and the zone in the vicinity of the rod core; the three zones have been found to exhibit different amorphous structures.
Effect of Cooling Rate on Magnetic Properties, Size and Type of Structural Defects in the Volume of Bulk Amorphous Fe36Co36B19Si5Nn4 Alloy in the Form of Rods of Various Diameters
Authors: Nabiałek M. , Dobrzanska-Danikiewicz A. , Lesz S. , Pietrusiewicz P. , Szota M. , Dospiał M.
Published: April 2014

This paper presents the results of microstructure and magnetic properties analysis for bulk amorphous samples of Fe36Co36B19Si5Nb4 alloy in the form of rods of 1 mm, 2 mm, and 3 mm diameters in the as-cast state, produced using the method of injecting liquid alloy into cooled copper mold. The main purpose of the research was to examine the effect of solidification speed of the liquid material into amorphous state on the shape of initial magnetization curve as well as to determine the type and size of structural defects occurring in the volume of the material. In order to achieve these objectives, the magnetization measurements were carried out, which according to H. Kronmüller’s theory on magnetization behavior near the area called reaching the ferromagnetic saturation, allow to determine the type, size, and surface density of structural defects occurring in the volume of the sample. The analysis of reduced magnetization curves indicates that solidification speed of the liquid alloy into the amorphous state is the main determining factor for the shape of initial magnetization curve and for the type and size of structural defects formed in the sample, which affects such magnetic parameters as: coercive field (HC) or saturation magnetization (MS).
Determination of a Mass Transfer Area during Metal Melting in a Vacuum Induction Furnace
Authors: Golak S. , Przylucki R. , Barglik J.
Published: April 2014

In the paper, a simulation model that allows for determination of the actual surface area of inductively stirred liquid metal and the value of metal near-surface velocity during its melting is presented. Also, the effects of induction furnace working frequency on both parameters are demonstrated. The simulation was performed for copper and liquid steel that were melted in two different induction furnaces. The calculation results were also used for determination of coefficients of copper mass transfer in liquid steel and of antimony mass transfer in liquid copper during their stirring in the discussed furnace.
Influence of Deformation Process by ECAE on Structure and Properties of AZ61 Alloy
Authors: Boczkal S. , Lech-Grega M. , Płonka B.
Published: April 2014

The structure and properties of AZ61 alloy after deformation by ECAE were characterised. Alloy structure was examined after the successive passes of ECAE process, to study the effect of deformation on the morphology of γ phase precipitates and the size and shape of grains. Based on EBSD analysis, the occurrence of high angle boundaries was stated. An attempt was made to describe the mechanisms that are operating when the deformation route is changed at 300°C in the AZ61 alloy processed by ECAE method. Alloy hardness after the first cycle of deformation was stabilised at the level of 80-90 HB. Based on the hardening curve and the occurrence of high angle grain boundaries (>15°), the possibility of further deformation of the AZ61 alloy was confirmed.
Effect of Severe Plastic Deformation on Microstructure and Properties of Polycrystalline Aluminium Al99.5
Authors: Leszczyńska-Madej B. , Pałka P. , Richert M.
Published: April 2014

Polycrystalline aluminium Al99.5 was deformed through the combination of equal-channel angular pressing (ECAP) by B route (4, 8 and 16 passes) and then by the hydrostatic extrusion (HE) using the cumulative way of deformation, just to the achieving the final wire diameter d = 3 mm. The microstructure of samples was investigated by means light microscopy (LM). Additionally the microhardness measurement and the tensile test were performed to determine the level of aluminium hardening. The texture was determined by using the Brucker Advance D8 equipment.

The aim of the research was to determine the influence of severe plastic deformation exerted in the process of equal-channel angular pressing (ECAP) and hydrostatic extrusion (HE) on the microstructure and properties of polycrystalline aluminium Al99.5.

The microstructure observations both after the HE process and the combination of ECAP + HE revealed the elongated to the extrusion direction grains and numerous bands and shear bands. The bands and shear bands most clearly revealed at the perpendicular section. The performed investigations showed that with the increase of the deformation the aluminium level hardening increase. The highest properties of tensile strength - UTS = 218 MPa and microhardness level HV0.1 = 46 were obtained after 8 ECAP + HE.
Producing Ultrafine Grain Structure in AZ91 Magnesium Alloy Cast by Rapid Solidification
Authors: Szymanek M. , Augustyn B. , Kapinos D. , Boczkal S. , Nowak J.
Published: April 2014

The paper presents the technological aspect of the process of casting, crushing and plastic consolidation of semi-finished products from magnesium alloy. The aim of this study was to produce by the rapid solidification process a magnesium alloy from the MgAl9Zn1 family in the form of ribbons with ultrafine grain structure. The material cast in the melt spinning device was next crushed and subjected to the operation of cold consolidation and hot extrusion. The paper presents different stages of the process, including initial characterisation of the obtained material.
Ultrafine Grain Refinement of AlMn1Cu and AZ 31 Alloys by SPD Process
Authors: Rusz S. , Cizek L. , Salajka M. , Tylsar S. , Kedron J. , Michenka V. , Donic T. , Hadasik E. , Klos M.
Published: April 2014

One of the ways to the more effective use of metallic materials is their processing by forming. At present in this the area the use of the process of severe plastic deformation (SPD process), leading to a refinement of the structure (materials with UFG structure) and thus to achievement of higher level of their utility value, is expanding. AlMn1Cu alloy is commercially produced aluminum alloy by the company Al Invest Bridlicna (the cast strip with a mild reduction by rolling up to 10% to the thickness of 10 and 15 mm, which has its uses especially in engineering. AZ31 alloy is commercially produced aluminum alloy after casting and extrusion at 400°C on final rod with 20 mm diameter. For experimental purposes from the belts of alloys the test samples of the underlying dimensions of 10x10 mm length 40 mm (geometry with channel deflection 20°) and 15x15 mm length 60 mm (geometry with helix matrix) in the direction of rolling were made. All three instruments are made of high tool steel - HOTVAR. For compare the influence of geometry ECAP tool on structure refining was used AlMn1Cu and AZ31 alloys were used three specially made tools ECAP, differing mainly in the construction design.
Comparison of Structure, Mechanical and Electrical Properties of Al Alloy Die Forged Parts Made with Use of Different Stock Material
Authors: Płonka B. , Korczak P. , Remsak K. , Lech-Grega M.
Published: April 2014

The paper presents the results of the die forging tests of a modified EN AW-6101 alloy with the addition of Zr, using two types of the feedstock materials. The first feedstock materials were ingots cast in a vertical semi-continuous process, the second feedstock materials were extruded rods. The die forging process was carried with parameters enabling “on line” heat treatment (T5 temper). For comparison, forgings were also heat treated to the T6 temper and to thermo-mechanical treated to the T8 and T9 temper. Then forgings made from both feedstock materials were characterised in terms of structure, mechanical properties and electrical conductivity.
Usable Properties of Magnesium Alloy ZK60A by Plastic Deformation
Authors: Plonka B. , Remsak K. , Nowak M. , Lech-Grega M. , Korczak P. , Najder A.
Published: April 2014

The object of this study was to develop parameters of plastic deformation process of magnesium alloy - ZK60A. The tests have showed that for this alloy it is possible to use the temperature of the plastic deformation process ranging from 350°C to 450°C. Samples were characterized by mechanical properties and structure in different heat treatment tempers. This magnesium alloy obtained in the T5 temper higher mechanical properties then T6 temper. The paper also presents research results of investigation of conversion coating on ZK60A magnesium alloy by anodic oxidation method in non-chromium solutions. It was found that the coating produced in non-chromium solutions show considerable increase of corrosion resistance of tested alloy.
Research of Liquid Aluminium Alloys at Particular Stages of Manufacturing Process
Authors: Dzik S. , Targowski W.
Published: April 2014

Requirements, placed by design engineers in relation to special castings, applied to gas filled high voltage switchgears PN-EN 50052:2002, are still higher. These demands concern to quality of machined sealing surface, assurance of castings leaktightness for a long time of operating and suitable strength during special bursting test. Manufacturer of such castings is obliged to use, among other things, high quality new alloy and guarantee proper metallurgical treatment and liquid alloy control during metal melting and preparation, before filling the moulds.

Generally new alloy testing is made by its producer. Receiver checks testing results, according to effective procedures, during incoming inspection. Following tests are carried out during liquid alloy preparation (melting, degassing and inoculation): chemical composition test, thermal analysis and density index. To confirm that the process of liquid alloy control is correct comparative examinations were made, using new installations of companies such as Foseco, ALSPEK* H, and metallographic examinations of special samples with computer picture analysis.

All examinations were made for one heat of AlSi7Mg0.3 alloy (AC - 42100 according to PN-EN 1706:2011), at different stages of liquid metal preparation, such as: in melting furnace, after reladle, after refining and just before filling sand moulds. Additionally alloy purity index, hydrogen content in liquid alloy, porosity degree were determined and also analysis of inclusions was made.

Examinations with applying modern devices confirmed, that the process of preparation and testing of liquid alloy, intended to produce castings of special requirements, is correct. All applied refining treatments improved liquid alloy quality, eliminated number of inclusions, porosity and reduced hydrogen content. It is a base for stating that high quality alloy, correctly prepared and controlled before filling sand mould was used.

New Foseco devices can be used in foundries to verify their processes of alloy preparation and alloy purity evaluation on different stages, especially producing castings of high technical requirements.

The thixotropy phenomenon is strongly connected with the change of viscosity in time, while the of Navier-Stockes equation. The micro- and macroscale models are coupled using CAFE approach.
Casting of Titanium Alloys in Centrifugal Induction Furnaces
Authors: Karwiński A. , Lesniewski W. , Wieliczko P. , Małysza M.
Published: April 2014

This paper discusses technical problems related with casting of titanium alloys in centrifugal vacuum furnaces. The potentials of an analysis of the centrifugal casting process carried out in the Flow3D software CFD (Computational Fluid Dynamics) were presented. Simulations were carried out on a model set, which enables casting of two connecting rods for an I.C. engine. Changes in the mould filling process were examined for the three selected spinning velocities of the casting arm. The ranges of the metal flow velocity in mould were calculated as well as metal pressure in mould after reaching a predetermined spinning velocity. The results and the adopted mould geometry enabled determination of the magnitude of stress occurring in mould at the time of filling it with liquid titanium alloy. The paper presents a methodology for testing of the ceramic material strength using a four-point loading arrangement. The strength of the ceramic material was determined on samples heated at different temperatures. The obtained results enabled a thesis to be formulated that for pouring of moulds in a centrifugal vacuum furnace, the layered foundry ceramic moulds can be safely used, and the use of moulds that will provide the directional solidification of metal should be possible as well.
Growth Characteristics of the Oxide Layer on Aluminium in the Process of Plasma Electrolytic Oxidation
Authors: Gębarowski W. , Pietrzyk S.
Published: April 2014

During the formation of the oxide layer by plasma electrolytic oxidation (PEO), the electrochemical processes are accompanied by the plasma micro-discharges, occurring uniformly over the coated electrode. Application of an alternating current with strictly controlled electrical parameters can affect the character of the discharges, and consequently the properties of the obtained layers. When the cathodic current density exceeds anodic, at some point, a sudden change in the appearance of micro-discharges and a decrease in the intensity of the acoustic emission can be observed - in literature this effect is called “soft sparking”. In the present work, the evolution of the electrical properties of the layers at various stages of their formation has been characterized, using electrochemical impedance spectroscopy. The study showed a significant decrease in charge transfer resistance and increase in capacitance of the oxide layer after reaching the ”soft sparking”. This indicates a significant change in the structure of the oxide layer, in the barrier and main part, which is additionally confirmed by measuring the breakdown voltage.
Gastropods and periphytic algae relationships in the vicinity of a small hydroelectric plant on the Pas³êka River in northeast Poland
Authors: Zębek Elżbieta , Szymańska Urszula
Published: April 2014

This study of periphytic algae and gastropods differentiation on macrophytes, stones, and dam substrates and the relationships between these communities in the vegetative season of 2001-2003 was conducted in the vicinity of a hydroelectric plant on the Pasłeka River. Damming the river caused decreased water discharge upstream from the plant, and increased it downstream. Thus, oxygen conditions downstream from the plant improved, but high nutrient concentrations were also recorded. Generally, increased orthophosphate concentrations do not allow river waters to be classified as having good or maximum ecological potential. Damming contributed to changes in the growth conditions of the periphytic algae and gastropods and their differentiation. The highest biomass of periphytic algae was noted on the dam, while the highest gastropods biomass was noted on macrophytes. The periphytic algae was dominated by the diatoms Diatoma vulgaris and Melosira varians (epiphyton, dam) and the chlorophytes Ulothrix tenuissima and Spirogyra sp. (epilithon), while the gastropods were dominated by Lymnea stagnalis (macrophytes), Theodoxus fluviatilis (stones), and Radix balthica (dam). The relationship between the gastropods and the periphytic algae on macrophytes and the dam in spring and summer revealed an increase in gastropods biomass and a decrease in periphytic algae biomass. This was indicated by the negative correlation between the biomass of these communities.
The first polish tektites: preliminary sem investigation
Authors: Brachaniec Tomasz , Szopa Krzysztof , Karwowski Łukasz
Published: April 2014

In Lower Silesia, the first Polish moldavites were discovered. To recognize the primary chemical composition and check the morphology of investigated material SE and BSE images were used. The samples show presence of vesicles, which are one of the most typical features of tektite glass. Referring to the preliminary EDS results and comparing them with literature data, it can be assumed that in all cases the base material for all known moldavites was the same.
Dendrochronological potential of Ephedra equisetina from Zaravshan Mountains (Tajikistan) in climate change studies
Authors: Opała Magdalena , Niedźwiedź Tadeusz , Rahmonov Oimahmad
Published: April 2014

Samples from Mongolian Ephedra (Ephedra equisetina Bunge) was collected in the Zaravshan Mountains (the Fann Mountains), Tajikistan. The wood of Ephedra is ring-porous with well-defined growth rings. Annual ring widths were measured, individual series were first cross-dated and then averaged as a standard chronology. Correlations were calculated between the standard ring-width chronology and monthly climate data recorded in the weather station Iskanderkul. Dendroclimatological analysis showed that July temperature is the growth limiting factor of this species. Our study has shown high dendrochronological potential of Ephedra.
Evaluation of the wind conditions for the acquisition of energy from renewable sources on the base of Sosnowiec city
Authors: Sarapata Sonia
Published: April 2014

Inherent in the continuous development of civilization is a constant increase in demand for electricity. The result of this situation could be a threat to cover domestic demand for electricity generated from domestic sources. It is significant therefore, to increase the energy security of the country, as well as to generate a positive impact on the development and dynamics of social and economic processes which is carried by the development of renewable energy sources. A crucial argument for the need to implement new sustainable solutions is growing environmental degradation and pollution resulting from the acquisition and use of non-renewable energy resources. Renewable energy resource for interest of this analysis is the wind. A crucial feature of the wind is its high volatility. Wind speed is characterized by diurnal, seasonal and long-term variation. The study area is Sosnowiec city. The analysis covers the data from the period 2002 - 2011 obtained using a meteorological station located in the Department of Earth Sciences, University of Silesia in Sosnowiec. Analyzed data are observations of wind speed measured at the height of 10m above the ground - average values of 10 minutes. The mean and maximum daily, monthly and annual values of wind speed have been calculated, and on their basis, a relevant analysis have been made. Average wind speed value for the analyzed area of the analyzed period (2002 - 2011) is 1,70m/s, while the maximum wind speed value is 3,78m/s. Sosnowiec is located in zone IV - unfavorable for the use of wind energy.
Numerical and physical model study of a vertical slot fishway
Authors: Bombač Martin , Novak Gorazd , Rodič Primož , Četina Matjaž
Published: April 2014

This paper presents the results of an experimental and numerical study of a vertical slot fishway (VSF). A 2-D depth-averaged shallow water numerical model PCFLOW2D coupled with three different turbulent models (constant eddy viscosity, Smagorinsky and k - ε) was used. A detailed analysis of numerical parameters needed for a correct simulation of the phenomenon was carried out. Besides the velocity field, attention was paid to important hydraulic parameters such as maximum velocity in the slot region and energy dissipation rate ε in order to evaluate the performance of VSF. A scaled physical hydraulic model was built to ensure reliable experimental data for the validation of the numerical model. Simulations of variant configurations of VSF showed that even small changes in geometry can produce more fishfriendly flow characteristics in pools. The present study indicates that the PCFLOW2D program is an appropriate tool to meet the main demands of the VSF design.
Discharge coefficient of a rectangular sharp-edged broad-crested weir
Authors: Zachoval Zbyněk , Knéblová Michaela , Roušar Ladislav , Rumann Ján , Šulc Jan
Published: April 2014

This paper is concerned with the determination of the relationship for the calculation of the discharge coefficient at free overflow over a rectangular sharp-edged broad-crested weir without lateral contraction. The determination was made on the basis of new measurement in a range of the relative thickness of the weir from 0.12 to 0.30 and newly in a large range of relative height of the weir extremely from 0.24 to 6.8 which greatly expands the application possibilities of low weirs. In addition, the effects of friction and surface tension on the value of the discharge coefficient were evaluated as well as the effect of the relative thickness of the weir. The new equation for discharge coefficient, expressed using the relative height of the weir, was subjected to verification made by an independent laboratory which confirmed its accuracy.
Simulation and comparison of stream power in-channel and on the floodplain in a German lowland area
Authors: Song Song , Schmalz Britta , Fohrer Nicola
Published: April 2014

Extensive lowland floodplains cover substantial parts of the glacially formed landscape of Northern Germany. Stream power is recognized as a force of formation and development of the river morphology and an interaction system between channel and floodplain. In order to understand the effects of the river power and flood power, HEC-RAS models were set up for ten river sections in the Upper Stör catchment, based on a 1 m digital elevation model and field data, sampled during a moderate water level period (September, 2011), flood season (January, 2012) and dry season (April, 2012). The models were proven to be highly efficient and accurate through the seasonal roughness modification. The coefficients of determination (R2) of the calibrated models were 0.90, 0.90, 0.93 and 0.95 respectively. Combined with the continuous and long-term data support from SWAT model, the stream power both in-channel and on the floodplain was analysed. Results show that the 10-year-averaged discharge and unit stream power were around 1/3 of bankfull discharge and unit power, and the 10-year-peak discharge and unit stream power were nearly 1.6 times the bankfull conditions. Unit stream power was proportional to the increase of stream discharge, while the increase rate of unit in-channel stream power was 3 times higher than that of unit stream power on the floodplain. Finally, the distribution of the hydraulic parameters under 10-years-peak discharge conditions was shown, indicating that only 1-10% of flow stream was generated by floodplain flow, but 40-75% volume of water was located on the floodplain. The variation of the increasing rate of the stream power was dominated by the local roughness height, while the stream power distributed on the floodplain mainly depended on the local slope of the sub-catchment.
Impact of foreign direct investment on lower silesia’s economic development
Authors: Popławski Maciej
Published: April 2014

The paper presents research results concerning the impact of foreign direct investments on the economic development of Lower Silesia in the years 1999-2011. The first year analysed is 1999 - the year in which the new administrative division was introduced into Poland, where the number of provinces was reduced from 49 to 16, with 314 districts and 65 cities being given district rights (including communes which also accomplish the tasks of the district).1 The research takes into account the most important macroeconomic indicators presenting the region’s development, such as the GDP and investment and employment levels. These indices are based on data from the Statistical Office in Wrocław and the Central Statistical Office of Poland (GUS). Data on companies and entities with foreign capital have been correlated with the above-mentioned indicators to evaluate the foreign investment influence on the region’s economy
The influence of voting system on electoral participation of women in Poland
Authors: Niewiadomska-Cudak Małgorzata
Published: April 2014

In the research, there was taken an attempt to analyze to which extent the electoral system, currently functioning in Poland, influences electoral participation of women. In the elaboration electoral participation, as a form of political activity will concern realization of suffrage right. The electoral system as a category of political studies analysis is the one of the utmost importance. The matter of scientific understanding of the system concentrates an attention of researchers for a while. The analysis of contemporary voting systems became one of the basic tasks of empirical political studies. It is worth look closer at an mechanism, which became a tool for enhancing a participation of women in political life
Women in the management – cases of Turkish women progress in the it ranks
Authors: Bielikowski Jakub
Published: April 2014

It has been observed that Turkey, contrary to the country stereotypes, has high female participation in the IT, including professional and managerial positions. As in the women participation in the IT shows big differences among world’s countries, it seems important to research the possible sources of higher women participation in the IT in some countries. Based on the pilot of in-depth interviews with Turkish IT professionals the article looks preliminary into the following subjects: 1. What economic, social and cultural factors influence females’ IT choice in Turkey? 2. What were the success factors contributing to women employment and career in the IT in Turkey? 3. What barriers for IT management career progression have been identified by Turkish women? The article also proposes approach into further research into the subject.
A MEASURING SYSTEM WITH AN ADDITIONAL CHANNEL FOR ELIMINATING THE DYNAMIC ERROR
Authors: Dichev Dimitar , Koev Hristofor , Louda Petr
Published: April 2014

The present article views a measuring system for determining the parameters of vessels. The system has high measurement accuracy when operating in both static and dynamic mode. It is designed on a gyro-free principle for plotting a vertical. High accuracy of measurement is achieved by using a simplified design of the mechanical module as well by minimizing the instrumental error. A new solution for improving the measurement accuracy in dynamic mode is offered. The approach presented is based on a method where the dynamic error is eliminated in real time, unlike the existing measurement methods and tools where stabilization of the vertical in the inertial space is used. The results obtained from the theoretical experiments, which have been performed on the basis of the developed mathematical model, demonstrate the effectiveness of the suggested measurement approach.
MUltidimensional personnel selection through combination of TOPSIS and Hungary assignment algorithm
Authors: Safari Hossein , Cruz-Machado Virgilio , Zadeh Sarraf Amin , Maleki Meysam
Published: April 2014

This paper proposes an effective solution based on combined TOPSIS and Hungary assignment approach to help companies that need to assign personnel to different departments. An extension of TOPSIS (technique for order performance by similarity to ideal solution) combined by Hungary assignment algorithm is represented for this purpose. According to decrease resistance of employee opposite of recruitment of new employee, Decision criteria are obtained from the nominal group technique (NGT) and managers of each departments has been involved in decision making process. In the presented solution, managers of four departments have been involved in evaluating four candidates for their department and data is analyzed by TOPSIS and at the end, an effective fit between personnel and their corresponding department is presented.