bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Postoperative Masticatory Efficiency After Surgical Extraction of a Partially Impacted Mandibular Third Molar
Authors: Konstantinova D. , Nenova-Nogalcheva A. , Pechalova P.
Published: June 2019

The extraction of mandibular third molars is a traumatic procedure accompanied by marked clinical symptoms in the postoperative period. The aim of the present study was to determine the effects of the removal of a partially impacted mandibular third molar on the masticatory efficiency in patients in the early postoperative period.

Material and methods. A total of 47 participants, divided into two groups, took part in this pilot study. The first group included 33 patients with a mean age of 18.3 years (SD = 0.9 years), defined as the Control group; the second group involved patients with a mean age of 33.3 years (SD = 1.86), referred to as the Clinical group. The masticatory efficiency of the Clinical group patients was objectively double-checked using a Protab® test bite: once during the preliminary examination (prior to extraction of the wisdom tooth) and again 7 days after the surgical removal of the wisdom tooth. A sieve analysis was applied to determine the artificial test bite particle size and size distribution following mastication. Feedback on the Clinical group patients’ assessment of any subjective complaints was obtained through a questionnaire containing two questions considered relevant to patients’ masticatory efficiency. The data from the sieve analysis of each fraction were analyzed using the Statistics Software Package for Epidemiological and Clinical Research (IBM SPSS V.20.00).

Results. The data processing of all parameters tested prior to and after extraction of the wisdom tooth revealed statistically significant differences. Only the duration of chewing after the third molar extraction matched the chewing duration in the healthy control subjects (p = 0.198). The analysis of the feedback on the self-assessment of patients from the Clinical group demonstrated that prior to extraction all subjects (100%) experienced pain to a varying degree, whereas in half of the patients (50%) the pain disappeared following extraction. The Spearman’s test for correlation between mean particle sizes as well as the questionnaire feedback indicated a strong positive relationship with food trapping. Accordingly, the larger mean particle size was linked to the self-assessment of food trapping around the wisdom tooth prior to extraction (Spear-man’s Rho = 0.57, p = 0.032). There was also a correlation between the chewing time and the sensation of pain in the teeth adjacent to the extraction wound. The results suggested that the shorter duration of chewing was associated with a greater sensation of pain (Spear-man’s Rho = -0.61, p = 0.026).

Conclusion. The eruption of mandibular third molars causes difficulties in the masticatory process. A positive trend was observed towards normalizing of the chewing duration following extraction (t = -1.356, p = 0.198).
Shoulder Instability – Results of Different Methods of Treatment
Authors: Matev B.
Published: June 2019

The aim of this study is to present results after different procedures of surgical treatment of the unstable shoulder joint: arthroscopic stabilization; arthroscopic stabilization followed by the operative technique by Matev; the Latarjet procedure in cases with the presence of bone defects. From 2004 to 2017 291 patients aged between 15 and 35 years were operated at the University Hospital “Prof. B. Boychev”, Medical University − Sofia. 247 patients had anterior and 44 − combined shoulder instability. 173 of the patients were active athletes practicing different disciplines. The average age at the time of the first dislocation was 17 years. In 172 patients, the first dislocation occurred without significant trauma, 124 of them had anterior shoulder instability and 48 – combined shoulder instability. In 120 patients with anterior dislocations, there was history of a serious injury during the first accident. The number of dislocations varied between ten and fifteen in all patients. For the same period, 45 patients with significant bone defects requiring open surgery (Latarjet procedure) were operated. Among the patients with bone defects, the dislocations were between 8 and 30 before the first examination. There were 11 patients, who had undergone previous surgery in different hospitals and different number of relaxations after surgery were found. The data were evaluated radiographically and clinically. Functionally, the patients recovered according to a well-established protocol of physiotherapy and the external rotation regained the full range of motion. The patients were able to return to their sports activity. The successful results in all patients show that these combined operative techniques can be the method of choice in the treatment of a greater number of dislocations of the shoulder, especially in people who seek to quickly return to active sport activities.
The Heparanase Inhibitor (Sulodexide) Decreases Urine Glycosaminoglycan Excretion and Mitigates Functional and Histological Renal Damages in Diabetic Rats
Authors: Roshan-Milani S. , Khalilpour J. , Fard A. Abdollahzade
Published: June 2019

Background/objectives: Recent data suggest a role for heparanase in several proteinuric conditions. An increased glomerular heparanase expression is associated with loss of heparan sulfate in the glomerular basement membrane (GBM). The aim of the present study was to investigate the renal effects of heparanase inhibition in a diabetic experimental model.

Methods: Fifteen male Wistar rats (230 ± 20 g) were divided into three groups: 1) controls, 2) diabetics (STZ, 50 mg/kg, dissolved in saline, ip), 3) diabetics + heparanase inhibitor (Sulodexide 1/5 mg/kg per day, gavage). The treatment started on the 21st day, for 21 consecutive days. The rats were kept individually in a metabolic cage (8 AM-2 PM) and urine samples were collected on the 21st and 42nd day. At study end blood, urine and tissue samples were collected for biochemical (blood BUN and Cr, urine GAG and Protein) and histological analyses.

Results: The results of this study showed that the heparanase inhibitor (sulodexide) significantly decreased urine GAG and protein excretion, urine protein/creatinine ratio and serum BUN and Cr in streptozotocin-induced DN in the rats. Pathological changes were significantly alleviated in the DN rats having received the heparanase inhibitor (sulodexide).

Conclusion: Our data suggest that the heparanase inhibitor (sulodexide) is able to protect against functional and histopathological injury in DN.
Osteonecrosis of the Jaws in Patients Receiving Anti-Angiogenic Drugs and Chemotherapeutics: Literature Review and Case Reports
Authors: Mihaylova Z. , Ugrinov R. , Aleksiev E. , Stanimirov P.
Published: June 2019

Medication-related osteonecrosis of the jaw (MRONJ) is a relatively rare but serious pathology associated with the use of bisphosphonates (BPs) and antiresorptive drugs in patients with bone metastases, multiple myeloma and osteoporosis. Various cases of patients with jaw bone necrosis due to BPs have recently been reported in the literature. Anti-angiogenic drugs are novel anticancer agents prescribed to patients with renal carcinoma, lung carcinoma, soft tissue metastases, etc. Anti-angiogenic drugs target the vascular endothelial growth factor’s (VEGF) signaling pathways via different mechanisms and thus inhibit tumor cell proliferation, neoangiogenesis and tumor growth. Several reports have suggested a higher incidence of MRONJ in patients treated with BPs in combination with anti-angiogenic drugs. However, there is currently no sufficient data in the literature about the risk of ONJ in patients taking anti-angiogenic drugs or cancer chemotherapy alone. We present two clinical cases of osteonecrosis of the jaw in patients treated with chemotherapy, but no history of BPs. In the first case the necrosis is related to the anti-angiogenic agent sunitinib in a patient with lung metastases and in the second case- to complex chemotherapy in a patient with acute myeloid leukemia. We recommend conservative treatment with antibiotics in both cases, together with antiseptics and surgical removal of the necrotic bone following total demarcation of the sequesters.
The Centenary of Professor Arpád Tesár
Authors: Tesár Alexander
Published: June 2019

On 1st February 2019 is celebrated the birthday centenary of great Slovak scientist and engineer - professor Arpád Tesár (1919 - 1989). His name is connected with many bridges, engineering structures and scientific works being appreciated by the technical community worldwide.
The Late Gothic Portal in Trebišov Pauline Order Church, Architecture and Geometry
Authors: Grúňová Zuzana , Borošová Michalcová Miloslava , Vesztróczy Éva
Published: June 2019

Gothic architecture is one of the oldest surviving architecture in Slovakia. The Church of Pauline Order in Trebišov has many building phases; its entrance stone portal belongs to the later phase dated about the second half of the 15th century. Paper focuses on an architectural features and geometry of this portal. Portal has clearly a geometrical construction that is compared to another late gothic portal from church in Handlová. Conclusion suggests, that ratio of the entire portal dimensions is close to 4 : 3, proportions of jamb and opening widths are 1 : 4 : 1 part of the overall portal width and there highly probably existed some simple method of determining position of pointed arch arches.
Valorization of Crushed Glass as a Potential Replacement for Sand in Cement Stabilized Fly Ash Bricks
Authors: Saraswathy R. , James Jijo , Pandian P. Kasinatha , Sriram G. , Sundar J. K. , Kumar G. Swarna , Kumar A. Sathish
Published: June 2019

The present study involved the utilization of crushed glass as an auxiliary additive in the manufacture of cement stabilized fly ash (CSF) bricks. The bricks were made with 1:1 proportion of fly ash and sand stabilized with 20 % cement. Crushed glass was used as replacement for the fine aggregate in increments of 10 % up to 40 % wherein the sand was completely replaced with crushed glass. The various mix proportions were then moulded into bricks with the addition of water by hand moulding method of forming the bricks and sun dried followed by sprinkle curing over a period of 21 days. The bricks were then subjected to compressive strength, water absorption and efflorescence tests to gauge its performance. The investigation revealed that the addition of crushed glass to the brick mix resulted in an increase in strength of the bricks, however, the maximum strength achieved could not achieve the strength of the control specimen. But the strength was higher than the minimum strength recommended by Bureau of Indian Standards (BIS) for stabilized blocks as well as burnt bricks. It also reduced the water absorption marginally while no efflorescence was seen in any of the combinations. A cost comparison revealed that the optimal combination with crushed glass was able reduce the cost of the brick by 20 %.
Comparison of 2D Grid Simulations for Flow Past Cylinder at High Reynolds Numbers
Authors: Lausová Lenka , Kološ Ivan , Michalcová Vladimíra
Published: June 2019

The paper focuses on the verification of the suitability of the SST k - ω model on the flow past a circular cylinder in 2D for a high Reynolds number. The study compares the results of drag and lifts coefficients with respect to different types of meshes and time steps. The mean velocity field in the wake region behind the cylinder is evaluated and compared to experimental data available from literature. The numerical simulations are solved using CFD codes in the ANSYS Fluent software and use the finite volume method.
Homophily in co-autorship networks
Authors: Stoica Adelina-Alexandra
Published: June 2019

The main purpose of this paper is to measure the impact that homophily, structural characteristics of the networks, number of citations of the alters and their Hirsch score have on the number of citations of an ego. I have chosen co-authorship networks as a subject of research because they have a great influence on knowledge and on the diffusion of ideas. The studied populations are represented by full-time academics affiliated to sociology departments in Romania, Poland and Slovenia. Ego-network analysis was used as research design. The data was analyzed using linear hierarchical regression. For all three populations the average number of citations of the alter has a considerable positive impact on the number of citations of the ego. Conversely, the Hirsch score of the alter has a negative impact on the number of citations of the ego. The data analyzed in this article claims that the assumptions about the positive impact of alter citations, network size and the betweenness score on the number of the authors citations are supported empirically.
The impact of transnational co-authorship on the scientific quality of academic researchers-Case Studies: Slovenia, Poland and Romania
Authors: Mihăilă Bianca Elena
Published: June 2019

The aim of this article is to contribute to the discussion about whether the scientific impact of an academic researcher (measured through bibliometrics indices as Hirsch score, citation scores or quantitative data about publications) can be accounted for by the presence of co-authors and the characteristics of the personal networks they are embedded in. With my study, I intend to demonstrate that there is statistical evidence between international co-authorship, measured through the number and the characteristics of international co-authors and the scientific impact of the researcher. Recent studies using bibliometrics and scientometrics approach shows that papers published with international co-authors may result in a higher citation rate than the ones written in a purely national manner (with national co-authors) (Glanzel & Schubert, 2001; Schmoch & Schubert, 2008). In the literature that addresses these issues, the main focus is put on international co-authorship, but my opinion is that the concept has undergone a series of methodological changes. I address these changes as a trend towards a transnational perspective. I explored the personal networks of university researchers, from three academic communities in the field of sociology. I analyzed the data using hierarchical regression models. This article is based on secondary data analysis starting from the data Hâncean used in 2016 (Hâncean & Perc, 2016). The data provided attribute and relational data for the focal nodes and their corresponding alters from Web of Science platform. Given the theoretical framework proposed by previous research (Adams, 2012; Hâncean & Perc, 2014; Glanzel & Schubert, 2004), I expected the scientific impact of an author to be positively influenced by the impact of the personal network he is embedded in. After running the analysis, the presence of transnational co-authors has a moderate impact on the citation distribution, especially for the Romania case. The biggest impact on the citation distribution, for all academic communities I included in the analysis, are the number of publications and the average number of co-authors’ citations. The description and the exploration of the data in all three communities of academic sociologists (Romania, Poland and Slovenia) will be used later in order to show new ways in which knowledge is transferred through the lens of a transnational perspective.
The Peculiarities of Remodelling Muscle Tissue of Rats Under the Vibration Influence
Authors: Kostyshyn Nazar M. , Kostyshyn Liybov P. , Servetnyk Marta I. , Grzegotsky Mechyslav R.
Published: June 2019

Study of the influence of vibration oscillations of different frequency, amplitude and vibration acceleration on the structural and functional state and mechanisms of muscle tissue remodelling. An experimental study was conducted on sexually mature male rats. The rats of the four experimental groups were subjected to vertical vibration oscillations of 15, 25, 50 and 75 Hz, respectively. It has been established that pathological changes in muscle tissue in the form of different variants of damage and remodelling tend to increase, which correlates with the frequency of vibration, amplitude and vibration acceleration level, as in the 2nd group, where the maximum permissible vibration levels did not exceed the established allowable norms, and in other groups of animals, where the permissible levels of total vibration were exceeded. By increasing vibration acceleration for more than 1.25 m/s2 (0.13 g, frequency more than 25 Hz and amplitude of 2 mm), severe damages are observed in the form of alterative changes of muscle fibres with the disappearance of transverse strain, homogenization of sarcoplasm, fragmentation with dissociation fibres on separate beams, partial and subtotal myocytolysis, and necrosis of separate fibres. Inflammation is rapidly increasing with the increase in the frequency of vibration and the level of vibration acceleration for more than 5.0 m/s2 (0.51 g).
Remission of Late-Onset Post-Liver Transplantation Non-Hodgkin Lymphoma
Authors: Stardelova Kalina Grivcheva , Stojanovik Aleksandar , Jovanovska Rozalinda Popova , Stavrik Sonja , Dimitrova Magdalena , Kostova Neda Milevska , Serafimoski Vladimir
Published: June 2019

We describe the clinical course of a patient who developed high-grade lymphoma during immunosuppression treatment with cyclosporine A, following liver transplantation. After anti-neoplastic polychemotherapy treatment, the remission of lymphoma was confirmed and maintained for over four years.

The patient, a 27 year old female had liver transplantation at the age of 17, due to acute liver failure, caused by non-diagnosed Wilson disease. Nearly seven years post-transplantation, the patient was diagnosed with non-Hodgkin B-cell lymphoma (NHBCL), potentially induced by Cephalosporin A therapy. After the treatment with rituximab and CHOP therapy (r-CHOP protocol), remission was determined using computer tomography. Remission is maintained to date.

A review of reported cases of post-transplant lymphoproliferative disorders (PTLDs) in liver transplanted (LT) patients showed that the onset of PTLDs is the highest in the first year after transplantation. In addition, remission rates of NHBCL in LT patients are not much elaborated in the literature. It is our opinion that the presented case is rare, both from the aspect of timeline of occurrence of the PTLD and the achieved remission, using r-CHOP protocol.
Importance of 6-Thioguanine Nucleotide Metabolite Monitoring in Inflammatory Bowel Disease Patients Treated with Azathioprine
Authors: Pavlovska Kristina , Petrushevska Marija , Gjorgjievska Kalina , Zendelovska Dragica , Ribarska Jasmina Tonic , Kikerkov Igor , Gjatovska Liljana Labachevska , Atanasovska Emilija
Published: June 2019

The active metabolite of azathioprine, 6-thioguanine nucleotide (6-TGN) is the main component responsible for the immunosuppressive effect in treatment of inflammatory bowel disease (IBD).

The aim of this study was to assess the correlation between the concentration of 6-thioguanine nucleotide and disease activity, azathioprine-related adverse effects and time duration of treatment in patients with inflammatory bowel disease.

Thirty-four patients were included in this study. Type of disease, gender, time duration of therapy and adverse effects were recorded. Metabolite concentration was determined by high performance liquid chromatography.

Twenty-one percent of patients have experienced an adverse effect, with leucocytopenia most commonly occurring (42.9%). More adverse effects were registered when patients were treated with azathioprine in a period of less than 3 months in comparison to the group of patients that have been under therapy between 3-12 months and more than 12 months (p˂0.05). Most of the patients that presented any adverse effect had high 6-TGN concentration (>450 pmol/8x108 Er). The mean value of 6-TGN metabolite concentration in IBD patients treated with azathioprine was 437.46 pmol/8x108 Er ± 198.82 pmol/8x108. The time duration of azathioprine treatment did not have any significant impact on the achieved 6-TGN concentration (p>0.05).Twenty patients (58.9%) had achieved remission after therapy initiation with azathioprine.

More alertness is recommended to clinicians towards patients in the first 3 months of the therapy. Our study demonstrated that higher 6-TGN concentration is associated with azathioprine toxicity.
Posterior Reversible Encephalopathy Syndrome (PRES) in Children Undergoing Allogeneic Stem Cell Transplantation
Authors: Veljanovska Aleksandra Pivkova , Stojanoski Zlate , Chadievski Lazar , Stavridis Irina Panovska , Trajkova Sanja , Cevreska Lidija , Georgievski Borche
Published: June 2019

Posterior reversible encephalopathy syndrome (PRES) is one of the most serious complication after allogeneic stem cell transplantation in paediatric setting. It is most commonly reported as adverse event of immunosuppressive strategies during transplantation. We present a case of a 7 years old girl with myelodysplastic syndrome (MDS) treated with allogeneic stem cell transplantation (ASCT) at our department. Diagnosis of PRES was confirmed by imaging techniques during the first month after transplant and it was very likely connected with cyclosporine neurotoxicity. The aim of this article is to present our first experience in diagnosing and treating PRES in paediatric stem cell transplantation. Our experience showed that PRES is one of the reasons for higher transplant related mortality in children. Early prediction of factors contributing to PRES and closely monitoring of patient’s vital signs, especially blood pressure, neurological status and vision are the main contributors for challenging the patient with another immunosuppressive agent that has less neurological toxicity. Still studies have to be initiated to confirm the influence of PRES on transplant outcome.
Preliminary geophysical investigation for road construction using integrated methods
Authors: Amosun Joel Olayide , Olayanju Gbenga Moses , Sanuade Oluseun Adetola , Fagbemigun Tokunbo
Published: June 2019

Integrated geophysical methods have been used to investigate the competency of the subsoil. The geophysical surveys conducted involve very low-frequency electromagnetic (VLF-EM) and electrical resistivity (ER) methods (dipole-dipole). ABEM Wadi and Ohmega resistivity meter were used to acquire VLF-EM and ER data, respectively, along two traverses. Station interval of 5 m was used for the VLF-EM survey, while inter-electrode spacing for dipole–dipole was 10 m; the inter-dipole expansion factor (n) ranged from 1 to 5. KHFFILT software was used to generate VLF-EM profiles and pseudosection, while DIPRO software was used for ER. Results from the ER method revealed the pattern of resistivity variations within the study area. The low resistivity values (11–25 Ohm-m) observed at the southern part of the study area could be attributed to changes in clay contents and degree of weathering in the subsurface. The results from the VLF-EM investigation revealed the presence of near-surface linear geologic structures of varying lengths, depths and attitudes, which suggest probable conductive zones that are inimical to the foundation of the road subgrade.
Suitability Assessment of Two Types of Heat Exchangers for High Temperature, Naturally Circulating Helium Cooling Loop
Authors: Dzianik František , Gužela Štefan , Puškášová Eva
Published: June 2019

The paper presents a comparison of the process properties of two types of the heat exchangers designed for the heat removal from a high temperature helium cooling loop with steady natural circulation of helium. The first considered heat exchanger is a shell and tube heat exchanger with U-tubes and the other one is a helical coil heat exchanger. Using the thermal and hydrodynamic process calculations, the thermal performance of the two alternative heat exchangers are determined, as well as the pressure drops of flowing fluids in their workspaces. The calculations have been done for several defined operating conditions of two considered types of heat exchangers. The operating conditions of heat exchangers correspond to the certain helium flow rates.
Geometrically Similar Rectangular Passive Micromixers and the Scaling Validity on Mixing Efficiency and Pressure Drops
Authors: Naresh Veldurthi , Bodas D. , Sunil Chandel , Tejashree Bhave
Published: June 2019

In the present work, two geometrically similar passive geometries with dumbbell shape were designed to perturb the dominating viscous forces in the low Reynolds number (Re) flows of the fluids. The geometries were designated as PDM-I and PDM-II, in which all the linear dimensions were related by a constant scale factor of two. Mixing efficiencies and pressure drops of the species at various Reynolds number (Re) were calculated to estimate the scaling effect validations. Finally, the geometrically similar PDM geometries were fabricated in Polydimethylsiloxane (PDMS) polymer to evaluate the scaling effect on the mixing efficiencies of the dyes and validated with the simulation results of species mixing.
The Assessment of the Residual Stresses Influence on Generation of the Infringement in Shape-Complex Supporting Members
Authors: Pástor Miroslav , Čarák Peter , Gömöry Imrich
Published: June 2019

The aim of the paper is to assess the effect of residual stresses on the damage of the slide bearer. To quantify the residual stresses, the drilling method using SINT MTS 3000 drilling machine was chosen. The tensometric rosette application areas were determined based on the analysis of the results obtained by numerical modeling using the finite element method. Experimental measurement was performed on one unused slide bearer and on the other one, which during its present operation had completed about 9.106cycles. At the end of the paper, the analysis of the measured residual stress values in chosen locations is presented.
The Calculation of the Contact Force and the Contact Width of Shaft Seals
Authors: Šlesar Peter , Jančo Roland
Published: June 2019

The aim of the article is to point out the sealing efficiency of the two-language seal of the water pump bearing when radially deflecting the shaft within radial clearance. In order to obtain a radial displacement of the shaft at a location under a two-language seal, dynamic bearing simulation was performed using the MSC Adams program. The largest radial deviation of the shaft was applied in final seal analysis where the contact pressure changes on the individual tongues of the seal were recorded.
Numerical Simulation of Heat Transfer Behavior of Dissimilar AA5052-AA6061 Plates in Fiction Stir Welding: An Experimental Validation
Authors: Vishwanath M. M. , Lakshamanaswamy N. , Ramesh G. K.
Published: June 2019

Fiction Stir welding (FSW) a unique type of metal joining process in solid state, where the heat generation takes place due to the friction action between the rotating tool and the work piece. It is generally used to join all series of Aluminum alloys with good strength and other metallic alloys finds difficult to weld through regular fusion welding techniques. The metal joining takes place in the solid state as the metal to be welded reaches about 80% to 90% of its melting temperature. The joining of metals in friction stir welding does not require any filler metals all classes of Aluminium alloys can be joined and in some desirable cases dissimilar metal compositions and Aluminiun metals composites can be joined satisfactorily. Joining of dissimilar metals has become a trend in the industries like aerospace, automotive chemical etc. as the helps in reducing the cost incurred by eliminating the costly materials. In the present study an experimental investigations are made to study the heat transfer behavior by determining the temperature distribution in AA5052-AA6061 plates during the Friction Stir welding. A three dimensional transient analysis is made by using ANSYS finite element analysis software. Thermocouples are placed at the suitable locations and the same point the temperature readings were taken from the simulation results. The experimental data is compared with the numerically simulated results. The numerical simulations results obtained are in better agreement with the experimental data obtained.
Research of Dependence of the Damage Area on Tow Width on Filament-Wound Composite Tubes
Authors: Bobrowska Marcelina , Barcikowski Michał , Rybczyński Radosław
Published: June 2019

This paper explores the effect of tow width on the damage area produced by high velocity impacts on glass fiber/epoxy composite structures made by filament winding. The subject of the research were a four-layered composite tubes that have been designed using matrix method. The method was used to select mosaic patterns with different rest of the winding stroke and number of interlaces, which are places of stress concentration and which affect the strength of the composite. The narrowest (5 mm) and the widest (17 mm) tow width available was chosen. Composite filament-wound structures were subjected to a high velocity impact by a 2.0 g spherical hardened steel impactor propelled to a velocity of 140 ÷ 170 m/s using a gas gun. It was observed that dependence of the damage area on tow width on filament-wound composite tubes is possible.
Process of Preparing and Laying Carbon Prepregs
Authors: Sokołowski Michał
Published: June 2019

This article contains information on the technological process involved in the production of a composite structure with carbon-epoxy prepregs including critical parameters of the process. The information in the publication shows respectively:

1. Using composite components for constructing the airframe,

2. ways of storing and preserving carbon prepregs on a matrix of thermosetting resins,

3. specific types of varying weave fabrics used in the prepregs,

4. way of preparing material for the process,

5. cutting tools,

6. preparing swage,

7. list of the most popular materials, their characteristics, pros and cons of their applications,

8. issues related to types of release agent,

9. parameters of selecting release agents in the process of manufacturing structures with carbon prepregs,

10. process of laying plies in a layered structure,

11. defects which result from improper material laying in swage,

12. preparing the structure for heating and technical parameters of the process.
Importance of Personal Data Protection Law for Commercial Air Transport
Authors: Zadura Dawid
Published: June 2019

In the review below the author presents a general overview of the selected contemporary legal issues related to the present growth of the aviation industry and the development of aviation technologies. The review is focused on the questions at the intersection of aviation law and personal data protection law. Massive processing of passenger data (Passenger Name Record, PNR) in IT systems is a daily activity for the contemporary aviation industry. Simultaneously, since the mid- 1990s we can observe the rapid growth of personal data protection law as a very new branch of the law. The importance of this new branch of the law for the aviation industry is however still questionable and unclear. This article includes the summary of the author’s own research conducted between 2011 and 2017, in particular his audits in LOT Polish Airlines (June 2011-April 2013) and Lublin Airport (July - September 2013) and the author’s analyses of public information shared by International Civil Aviation Organization (ICAO), International Air Transport Association (IATA), Association of European Airlines (AEA), Civil Aviation Authority (ULC) and (GIODO). The purpose of the author’s research was to determine the applicability of the implementation of technical and organizational measures established by personal data protection law in aviation industry entities.
Flow Visualization Over an Airfoil with Flight Control Surfaces in a Water Tunnel
Authors: Filipiak Daniel , Szczepaniak Robert , Zahorski Tomasz , Bąbel Robert , Stabryn Sebastian , Stryczniewicz Wit
Published: June 2019

This paper demonstrates the feasibility of using-a water tunnel for the visualisation of flow in airfoils with flight control systems in the form of slots and flaps. Furthermore, the issue of using water tunnels for scientific and training purposes was explained. The technology of 3D printed models for practical tests in a water tunnel was also presented. The experiment included conducting flow visualisation tests for three airfoil models: with the Clark Y 11.7% as the base airfoil and the same airfoil with a slot and a flap. Moreover, a modification to dye injection system was introduced. The presented results of flow visualisation around models with the use of dye, confirmed the effectiveness of the applied methodology. The results and conclusions may be utilized to verify most flow-related issues in hydrodynamic tunnels and can also be used as a training element.
Quality Control Process of Manufactured Composite Structures
Authors: Szymański Rafał
Published: June 2019

The paper includes a description of the composite material used in the aviation industry. It presents the technological development of composites in terms of their use in the most important elements of the aircraft structures, such as a spar and aircraft wing sheathing, which are subjected to high loads during operation. The type of the material implemented for production was listed and the most commonly occurred incompatibilities during the carbon pre-impregnate manufacture and transport were described.

The manufacture diagram of composite elements with a polymer matrix was presented and the quality control system carried out at each mentioned stage (material storage, defrosting, cutting of dies, structure forming, polymerisation) was discussed.

The methods of non-destructive tests of carbon laminates in a polymer matrix were also listed, describing the most effective of them, i.e. a method of ultrasonic tests.

The conclusions were drawn and the development possibilities of ultrasonic tests both in terms of quality improvement and reduction of time for detecting incompatibilities in composite structures were described.
Tests of Damage to Inconel 718 Alloy Used in Aviation
Authors: Krysztofik Józef , Socha Grzegorz
Published: June 2019

Inconel 718 alloy was tested. A new type of specimens of variable cross-sectional area measuring part was used for the tests. This provided a continuous distribution of plastic strain in that part of the sample. The proposed method enables to replace a series of specimens by one specimen. The degradation of the material was obtained by static tensile test and the creep test. The permanent deformation that varies along the specimen axis allows for an analysis of damage induced by a plastic deformation. The degradation of the alloy corresponds with the changes of acoustics properties of the material - attenuation of ultrasonic waves. It allows to detennine the degree of damage to the material using a non-invasive - ultrasonic method. Using the damage parameter proposed by Johnson allows to obtain correlation between the non-destructive results and a damage degree of the material. The presented testing method delivers information about changes in the material structure caused by permanent deformation.
Analytical Redundancy in Control Systems for Unmanned Aircraft and Optionally Piloted Vehicles
Authors: Dołęga Bogusław , Kopecki Grzegorz , Tomczyk Andrzej
Published: June 2019

The article presents key properties of a module intended to estimate non-measurable state variables of an aircraft (a fixed-wing aircraft). Sample calculations are applicable to the MP-02A Czajka light Optionally Piloted Vehicle (OPV). The quality of flight parameter values’ estimation is illustrated by comparing flight parameters of the MP-02A Czajka aircraft recorded during actual flight with estimated values of respective parameters calculated during simulation of selected sensor faults. This experiment allows to evaluate the usefulness of the analytical redundancy mechanism that determines attitude parameters (roll, pitch and heading angles) and navigational variables (airspeed, altitude and geographic coordinates).
Reconfiguration of Unmanned Aircraft Control System
Authors: Żugaj Marcin
Published: June 2019

Reliability of unmanned aircraft is a decisive factor for conducting air tasks in controlled airspace. One of the means used to improve unmanned aircraft reliability is reconfiguration of the control system, which will allow to maintain control over the aircraft despite occurring failures. The control system is reconfigured by using operational control surfaces, to compensate for failure consequences and to control the damaged aircraft. Development of effective reconfiguration algorithms involves utilization of a non-linear model of unmanned aircraft dynamics, in which deflection of each control surface can be controlled independently.

The paper presents a method for an unmanned aircraft control system reconfiguration utilizing a linear and nonlinear model of aerodynamic loads due to control. It presents reconfiguration algorithms, which differ with used models and with optimization criteria for deflections of failure-free control surfaces. Additionally it presents results of a benchmark of the developed algorithms, for various types of control system failures and control input.
Temperature Measurements in the Detonation Chamber Supplied by Air from Centrifugal Compressor and Gaseous Hydrogen
Authors: Kindracki Jan
Published: June 2019

In this paper, the experimental results of a detonation chamber fed by air from a centrifugal compressor are presented. The detonation chamber was equipped with many different sensors, mostly thermocouples, which were placed in 11 different positions. The distribution of temperature changes along the chamber and radial temperature profile at the outlet are provided. The results here confirm the existence of high mixture stratification. Such mixture stratifications and temperature profiles may be used as an additional chamber wall cooling method. The experiments performed, address key issues regarding the chamber choking problem caused by turbines. The relationship between the turbine performance and detonation chamber are crucial for proper control of turbine jet engine.
Measuring and Testing the Parameters of a Battery Pack Designed for Powering Unmanned Aircraft Systems at Various Temperatures
Authors: Mazur Anna M. , Korniluk Tomasz , Domański Roman
Published: June 2019

This paper describes results of tests dedicated to studying – in simulated environmental conditions – operation of a battery pack designed for powering unmanned aircraft systems. In particular, the tests concerned determining the electrical parameters of battery packs, with and without radiators, during their operation in changing environmental conditions and resistance to large temperature fluctuations. Amicell, a high density lithium polymer battery manufactured by the Israeli Amit Industries ltd., was selected for testing. The test results present characteristics of the batteries tested in different temperatures and allow for designing and trying out proper battery protections against environmental conditions, with the intention to attain continuous and correct operation. The tests have been carried out in the accredited Environmental Test Laboratory which is part of the Department of Avionics of the Institute of Aviation in Poland.
Individual Autonomous Navigation System
Authors: Popowski Stanisław , Dąbrowski Witold
Published: June 2019

The article presents the Individual Autonomous System Navigation (IANS) supporting–rescuer or firemen in terms of navigation. Basic assumptions, which such a system has to fulfill in terms of functionality and accuracy, are presented. The concept of the ISAN system is based on the implementation of inertial navigation system which the only one to permit fully autonomous functioning. Measurement sensors of the navigation system with microprocessor board are placed in the rescuer’s shoe. To limit the escalation of the navigation errors value, which in the case of inertial navigation rises exponentially, a procedure of navigation parameters upgrading at every step of the rescuer is introduced to the proposed system. This procedure guarantees the required accuracy of navigation achievement. The article describes a developed and manufactured demonstrator of the technology and presents main results of its research. The research conducted in a building consisted in walking on the same level several hundred meters in less than 10 minutes. A walking test with a change of walking height was also performed in order to estimate the accuracy of the vertical channel. Results of the demonstrator’s tests let us conclude that the error of navigation is below 1% of the travelled distance and the accuracy is linear in respect to time. The achieved accuracy is fully sufficient for a practical IANS application.
Manufacturing and Testing of Carbon Composite Samples Intended for Aviation
Authors: Szymański Rafał , Zięba Mateusz
Published: June 2019

The paper presents the manufacturing technology and quality control of samples made of composite materials intended, inter alia, for aircraft elements. The samples are made from carbon fiber reinforced prepreg in a polymer matrix which is commonly used in the aerospace industry. The authors described the dimensional requirements for samples made of composite materials for strength testing, and the main stages of production which have a direct impact on the quality of composite samples. Also presented is the technological process of producing flat carbon composite panels for composite samples, cutting the produced panels with a CNC plotter, cutting the samples on a conventional milling machine, and surface treatment of the samples on a surface grinder. The machining parameters that were experientially found to be optimal for the milling and grinding of carbon samples are specified as well. Finally, the method of quality control of the ready composite samples is described and solutions are presented to improve the production of high-quality samples.
Designing and Building Heavy Lifting Modification of a Radio Controlled Helicopter
Authors: Górzyński Mikołaj , Bibik Przemysław
Published: June 2019

The paper presents the heavy lifting modification of radio controlled T-Rex 700 DFC PRO helicopter which was originally designed as acrobatic machine. The purpose of designing machine like this is a need for a cheap and reliable machine specifically designed to carry weights for research and development purposes. Thanks to its design there is a possibility to attach to it a measuring apparatus, modules like auto-pilot, and weights. It can be also used to test wide range of rotors and other components which makes it very universal research tool. To achieve those goals the whole frame and landing gear has been redesigned using NX 11 CAD/CAM/CAE to achieve desired cargo space and weight distribution. Additionally the tail has been lengthened to allow use of the rotors with bigger diagonal. All the applied changes has been made to increase the machine payload. The designed elements were fabricated and the helicopter has been tested in flight. During the test flights several performance parameters were measured.
Wind Tunnel Tests of Influence of Boosters and Fins on Aerodynamic Characteristics of the Experimental Rocket Platform
Authors: Ruchała Paweł , Placek Robert , Stryczniewicz Wit , Matyszewski Jan , Cieśliński Dawid , Bartkowiak Bartosz
Published: June 2019

The paper presents results of wind tunnel tests of the Experimental Rocket Platform (ERP), which is developed in Institute of Aviation. It is designed as an easy accessible and affordable platform for microgravity experiments. Proposed design enables to perform experiments in microgravity for almost 150 seconds with apogee of about 100 km.

The full-scale model of the ERP has been investigated in the T-3 wind tunnel in Institute of Aviation. During the investigation, the aerodynamic loads of the rocket has been measured for the angle of attack up to 10° and the different rotation angle around the longitudinal axis (up to 90°, depending on the configuration). Three configurations has been investigated:

• without fins and boosters

• with fins and without boosters

• with fins and boosters

Additionally, the measurements of velocity field around the ERP using the Particle Image Velocimetry (PIV) has been performed.

Based on the wind tunnel test, an influence of fins and boosters on aerodynamic characteristics of the rocket has been described. Results of the wind tunnel tests show relatively high contribution of boosters in total aerodynamic drag. Some conclusions concerning performance and stability of the rocket have been presented.
Employees’ Perception on Corporate Social Responsibility Practices and Affective Commitment
Authors: Ahmed Nurulatika , Tahir Nor Suziwana
Published: June 2019

AbstractObjective – This research aims to study the employee’s perception on CSR practices and affective commitment in public listed companies in the area of Klang Valley, Malaysia. There were four dimensions on CSR practices that might affect the employee’s affective commitment in the organization which are economic responsibility, legal responsibility, ethical responsibility and philanthropic responsibility. Design/methodology – This study used Likert-Scale questions in order to answer both dependent and independent variables. A set of questionnaire was distributed to the employees who works in public listed companies in Klang Valley area regardless of their industry as population of this study. The data were analyzed by using Statistical Package for the Social Sciences (SPSS). Results – The findings from this study reveal that there is significant relationship of the employee’s perception on four dimensions of CSR practices and affective commitment. More than that, between all the four dimensions of CSR practices, economic responsibilities are found as the main element in influencing the employee’s affective commitment in work. The findings also show that role of gender does not moderate any relationship between dependent variables and independent variables. Research limitations/implications – This research adds the information on the level of affective commitment towards employees’ perceptions in the public listed companies in Malaysia as theoretical part that focused on the CSR dimensions based on the Carroll ‘s Model which are economic responsibility, legal responsibility, ethical responsibility and philanthropic responsibility with gender as the moderating variable in the study. The empirical part of this study has assessed that the economic, legal, ethical and philanthropic responsibility that can affect the level of affective commitment towards the employees’ perceptions in the public listed companies in the Klang Valley.
When It Comes to Editor-in-Chief Dr Guy G. Simoneau, Thanks Isn't Enough—It's More About Inspiration
Authors: Beattie Paul F.
Published: June 2019

After 15.5 years of guiding the Journal of Orthopaedic and Sports Physical Therapy (JOSPT) through its amazing progress, Guy G. Simoneau is stepping down as Editor-in-Chief, handing editorial leadership of the Journal to the very talented and able Clare L. Ardern, beginning with the July 2019 issue. In this editorial, we, the JOSPT/Movement Science Media Board of Directors, summarize some of Dr Simoneau's many achievements and humbly express our gratitude and that of the Editorial Board and publishing team for his overwhelming devotion to the JOSPT for nearly 2 decades. Orthop Sports Phys Ther 2019;49(6):363–365. doi:10.2519/jospt.2019.0102