bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Temperature and Deformation Rate on the Dynamic Viscosity of Ferrofluid
Authors: Frycz Marcin
Published: March 2013

This paper presents the results of studies which characterize the dynamic viscosity changes of ferrofluid in terms of changes of selected physical conditions of its work. Knowledge of the variation of the ferrofluids density, lubricity, and especially viscosity depending on the concentration of Fe3O4 magnetic particles, temperature, deformation speed and impact direction, type and value of magnetic induction, it is necessary to analyze the changes of operating conditions of the slide journal bearing ferrofluids lubricated. This theme is the broader context of the authors interests and his research. In this article has been briefly characterized the viscous properties of the tested ferrofluid. There also has been shown an analysis of the impact of changes in temperature and velocity of deformation on the change of ferrofluids dynamic viscosity. The paper has been summarized the observations and conclusions reached on the basis of analysis results.
Graph-Based Models of Compound Planetary Gear Boxes
Authors: Drewniak Józef , Zawiślak Stanisław
Published: March 2013

In the paper, graph-based models of planetary gears are presented. Especially, compound planetary gear boxes are analyzed. The rules of assignment of particular graphs are shortly described. Based upon these models, ratios for consecutive drives are calculated. Graph transformations are introduced aiming for presentation of every single drive separately. Kinematic equations are generated in algorithmic way based on the adequate subgraphs as well as their codes. Compatibility of results - obtained by means of different methods - was achieved. The presented method is simple and effective, moreover it can be used for other design tasks as e.g. optimization and further analyzes i.e. evaluation of effectiveness.
Measuring and Analyzing the Moment of Friction in Double-Row Ball Bearings
Authors: Korbut Robert , Nachimowicz Jerzy
Published: March 2013

On the basis of the experiment, the changes in the moment of friction in the double-row ball bearing were estimated. The experimental data indicated the presence of significant differences between the average values of the moment of friction in the whole spectrum of the rotational speeds that were examined. At the same time it was observed that there exist certain characteristic rotational speeds at which the given bearing is informed by a greater working resistance. It may indicate the presence of both optimal and unfavourable working conditions for these bearings; the conditions during which there occur minimal or, respectively, maximal resistances (in a given situation). The results of the examination were analyzed statistically; the after-examination samples were closely observed and this further visual scrutiny proved that during the work of the bearing, the lubricant was displaced.
Diagnostics Problems and Decisions of Low Rotation Speed Rotors with Antifriction Bearings
Authors: Barzdaitis Vytautas , Mažeika Pranas , Barzdaitis Vytautas V.
Published: March 2013

The essence of the paper was to design technical condition monitoring and failure diagnostic evaluation method of low rotation speed rotors with self-aligning antifriction roller bearings. The technical condition of bearings and failures of the cylindrical rollers and cylindrical wheels surfaces were tested in situ using mechanical vibration parameters measurement method. The theoretical part of the paper was constrained to the modeling of two cylinders in the case of different damages levels of the spherical roller bearings.
Temperature and Adhesion Influence on the Microbearings Operating Parameters
Authors: Wierzcholski Krzysztof , Miszczak Andrzej
Published: March 2013

In presented paper are elaborated the preliminary problems of thermo-hydrodynamic theory of lubrication for dependences between temperature, adhesive forces, and oil dynamic viscosity, in micro-scale inside super thin cylindrical boundary layer arising between two cooperating grooved cylindrical surfaces. In cylindrical micro-bearings are visible the large gradients of temperature changes and adhesion changes in very thin gap height direction. Hence the oil dynamic viscosity changes significantly in gap height direction. This fact implies the visible oil flow velocity changes and friction forces and the hydrodynamic pressure changes during the micro-bearing exploitation. Up to now the influence of adhesion forces simultaneously with temperature on oil viscosity changes and next on hydrodynamic pressure and load carrying capacity changes in cylindrical micro-bearing gap were not considered in analytical and numerical way.
The Influence of Temperature and Shear Rate on the Viscosity of Selected Motor Oils
Authors: Czaban Adam
Published: March 2013

One of the most important physical quantities which has an influence on bearings and micro-bearings functioning is the viscosity of a lubricant. The data about a viscosity value dependence on temperature and shear rate are essential for designing sliding friction pairs. In design calculations usually there is assumed that a lubricant is a Newtonian fluid, therefore viscosity is constant over the full range of shear rates. During operation of friction pairs the contamination particles get into a lubricant and this causes that the lubricant becomes a non-Newtonian pseudoplastic or viscoelastic fluid. A similar effect on lubricating oil properties have combustion products or special performance additives. Furthermore, a lubricating oil ages and wears out, i.e. during its operating the initial structure of a particles is destroyed which can cause the change of the oil viscosity and lubricity values. The aim of this work is to determine the dynamic viscosity values in dependence on temperature and shear rate for selected new and used lubricating oils. In this research motor oils for passenger vehicles and tractors were investigated. This paper presents the results of measurements of the viscosity changes, in dependence on shear rate and temperature, made for the new and used oils. One of the investigated oils is Superol CC-40, which was used in four-stroke 4562 cm3 diesel engine for twenty months, which corresponds to 250 hours of operating. The second of investigated oils is Shell Helix Ultra AV-L which was used in four-stroke 2000 cm3 diesel engine for ten months at a distance of 15 000 kilometers. The viscosity measurements for the new and used lubricating oils were made with the Thermo Scientific Haake Mars III rheometer, in the range of temperatures from 10°C to 120°C and of shear rates to 51000 1/s. Moreover, the analysis of wear products, contaminants and additives in the investigated new and used lubricating oils was made with the rotating disc electrode atomic emission spectrometer Spectro Incorporated Spectroil Q100, which gives possibility to determine 22 most common elements which occur in motor, turbine and gear oils. The obtained information will be used in future studies related to hydrodynamic lubrication of slide bearings and micro-bearings. It also may be useful for designing bearings and sliding friction pairs.
Tribological Behavior of Aerosol Particles in Acoustic Field
Authors: Vekteris Vladas , Tetsman Ina , Striška Vytautas , Mokšin Vadim
Published: March 2013

This work investigates agglomeration process of aerosol particles in presence of acoustic field. It is shown that besides orthokinetic and hydrodynamic interaction mechanisms, tribological interaction occurs in presence of acoustic field. This interaction depends on dynamic viscosity of the gas mixture above the liquid surface. The influence of acoustic field on tribological interaction between the aerosol particles was investigated both numerically and experimentally. The obtained results show the positive influence of acoustic field on agglomeration of aerosol particles.
Tribological Characteristics of Anodic Oxide Coat (AOC) Modified - Sealed up the Polymer
Authors: Służałek Grzegorz , Duda Piotr Jan , Wistuba Henryk
Published: March 2013

The paper represents the results of investigations conducted on the tribological test for the conditions of the friction of technically dry. Analysis stereological counter-specimen was subjected from AOC and AOC modified sealed up the polymers that is composites coats. Polymerization occurred at a temperature below the recrystallization temperature of the alloy EN AW 5251. The values of the coefficient of the friction, and the results of investigations AFM (atomic force microscopy) and the parameters of the roughness were compared. The tribological properties composites are investigated by using the pin-on-disk type rotational wear tester T-01 M. This paper shows models 3D of the AOC modified polymer and the mechanism of wearing. Tribological measurements show reduced wear and friction of the composite coatings as compared with the pure anodic oxide
Filtering Algorithms for 3D Range Image Analysis
Authors: Sioma Andrzej
Published: March 2013

This article is devoted to the methods of image analysis used in three-dimensional vision systems. Based on a sample set of 3D images, their defects resulting from the adopted three-dimensional image construction technique are discussed. Those defects are discussed in relation to the following parameters: speed of the vision system, power of the laser, laser mode, laser arrangement relative to the vision system sensor and relative to the tested surface. To illustrate the cases discussed, images showing the effects of selected parameters on the quality of mapping of the tested object onto a three-dimensional image were presented. The next part of the article discusses methods of range image filtering that removes or reduces the importance of defects of the adopted method in any control and measuring tasks. Particular attention is given to methods of removing data described as missing data.
Finding Bearing in Robot Navigation with the Use of the Kalman Filter
Authors: Sioma Andrzej , Blok Sławomir
Published: March 2013

In robotic systems navigation, it is necessary to determine the direction, in which the local coordinate system of a robot is to be turned in regards to the reference, global system. That direction from mathematical point of view is the rotation along one axis of the reference system, such that the reference system coincides with the local system associated with the body, which direction is defined. There is an assumption that the rotations along two other axes do not exist or they were taken into account in the calculations. A question appears: what is the measurement of the direction based on? The answer to that question is provided by nature [1, , because it has already solved this problem long ago. In migratory species such as birds, bees and fish, evolved magnetoreception abilities which allow an animal to detect the magnetic field of Earth. These abilities enable such organisms to navigate in space. In many devices magnetic field sensors called magnetometers are already used. However, magnetic measurements are subject to many kinds of distortions and errors. This paper shows a practical approach to a robot navigation problem.
Control Curves Method of Airframe Geometry Modeling
Authors: Kachel Stanisław
Published: March 2013

The paper presents the methodological approach to development of curves by selection of driving parameters with the application of the method to designing and reproduction of aircraft surfaces on the examples of both newly designed aircrafts and the ones that are already in service. The major assumptions are outlined that are necessary to develop the mathematical model of driving curves and surfaces, these assumptions served as the basis to draw up the relevant algorithms and to convert them to routines of the GRIP (Graphics Interactive Programming) language that is a part of the CAD/CAM/CAE Unigraphics system. These algorithms include the newly developed tool dedicated to design aircraft components and provided with inputs to the multi-criteria synthesis of the aerodynamic profiles of aircrafts. The study comprises also the assumptions to the newly developed algorithms dedicated to modelling of components incorporated into aircraft structures, these algorithms have been successfully implemented by the author.
An Induced Shaft Deflection for Rotating Shaft Crack Detection
Authors: Kulesza Zbigniew
Published: March 2013

Over the years various techniques have been developed to extract information on the dynamic state of the rotating machinery. This paper introduces a new method based on the phase data of the shaft rotation angle. Usually the phase data is omitted and only the frequency components of the vibration spectrum are taken into consideration. However, the transverse shaft crack has a specific angular location about the shaft axis. Therefore, it is supposed that by measuring the vibration response of the rotor deflected by an additional constant force applied perpendicularly to the shaft axis at different angular locations, different vibration signatures can be obtained. Such signatures can then be used to detect the crack. The method utilizes also the coupling phenomenon between the lateral/torsional vibrations of the cracked rotor, since the shaft is additionally excited by an external harmonic torque. The computer simulation study is based on the uncracked and cracked rotor models obtained by using the finite element (FE) approach. The results of the numerical analysis demonstrate the potential of the suggested method for the effective shaft crack detection.
Force Sensor for Laparoscopic Tool of RobIn Heart Robot
Authors: Kobierska Agnieszka
Published: March 2013

The design of a force sensor prototype as an equipment of a control system with force feedback to be used in the RobInHeart [1,2, telemanipulator system is presented. The main problems with placing the sensor on the laparoscopic tool are discussed. The method of decoupling impact of the gripper actuation force from the measurement is described. Also, the results of computer FEM simulations are shown.
Influence of CNC Machine Tool Technical Condition on the Geometrical Accuracy of Freeform Surfaces
Authors: Czerech Łukasz , Kaczyński Roman
Published: March 2013

The paper presents results of diagnostic tests for a CNC machine tool used for manufacturing elements with restricted freeform surfaces. Some selected errors possible to identify and estimate in numerically controlled machine tools using a QC20-W Ballbar were described and analyzed. The following parameters were subjected to thorough analysis: roundness deviation, perpendicularity and straightness deviation, cyclic error, backlash and reversal spike. The tests made it possible to carry out a correction of selected components of total tool positioning error and their influence on the process of geometric deviations of curvilinear surfaces produced with CNC machine tools.
Surface Structure of Components Created by Stereolitography
Authors: Dzionk Stefan
Published: March 2013

Stereolithography is an additive rapid prototyping method. This method is based on the principle of solidifying a liquid photopolymer (resin) by laser radiation. Models obtained with this method are characterized by a specific surface structure called stairstep effect. It causes that, the surface should be processed by additional finishing (postprocessing). To minimize the additional machining process, the model should be set in the relation to incremental layers so that the roughness of significant surfaces be optimal.
The Computer Simulation of Digital Measurement
Authors: Dzierżek Kazimierz
Published: March 2013

In the paper there is shown the way of increasing the accuracy of the Digital System of Position Measurement with the method of extrapolation.
The Digital Pre-Operative Planning of Hip Surgical Interventions
Authors: Michalíková Monika , Tóth Teodor , Rajťúková Viktória , Živčák Jozef
Published: March 2013

Computer technology has many applications in different fields of industry, health care and medicine. This encompasses paper-based information processing as well as data processing machines (Hospital information system or Clinical information system) and image digitalization of a large variety of medical diagnostic equipment (e.g. computer images of X-ray, MR, CT). The aim of the computer technology in medicine is to achieve the best possible support of patient care, preoperative surgery planning and administration by electronic data processing. At the present time in many countries of the worlds preoperative planning of interventions for lumbar joint is realized with caliper, protractor, plastic templates and x-ray images. Orthopaedic surgeons use transparent template radiographs as part of pre-operative planning in order to gauge the suitability and correct size of an implant. The newly developed CoXaM software offers a simple solution of the problems by using the digital x-ray images and handmade transparent plastic templates. The CoXaM software was developed in Visual Studio 2005 in the Visual C++ programming language at the Department of Biomedical Engineering and Measurement at the Faculty of Mechanical Engineering, Technical University of Kosice. The software was designed for pre-operative planning and helps to determine on the X-ray image a length dimensions, a center of rotation, an angle values. It enables the digitalization of plastic templates from several producers, which will assess the suitability of the type of implant.
Laboratory Tests of Shape Memory Alloy Wires
Authors: Rączka Waldemar , Konieczny Jarosław , Sibielak Marek
Published: March 2013

In this paper, tests on Shape Memory Alloy (SMA) wires for use in controlled actuators have been discussed. Selected static and dynamic characteristic curves being the result of experiments were presented in the article. Experiments were conducted at the Dynamics and Control of Structures Laboratory of the AGH University of Science and Technology. Laboratory tests of SMA wires used as actuators have been presented in the paper. Actuators made from the wires contract by about 4-5% of their length when heated, like small muscles, and loosen when cooled. SMA wires used as drives are significantly smaller than traditional solutions using motors or electromagnet to execute work. However, these actuators have flaws, such as strongly non-linear hysteresis. These are main problems in designing actuators, which is why SMA wires are often used in the construction of two-state actuators working as on-off actuators. The problems with SMA wires in their applications as drives are their static and dynamic properties, sensitivity to the environment, poor repeatability of production, non-linearity and hysteresis loop. The tested wires were made from a nickel and titanium alloy; this is an alloy which is often used in drive systems.
Ballizing Process Impact on the Geometric Structure of the Steel Tubes
Authors: Dyl Tomasz Cyryl
Published: March 2013

The paper presents effect of burnishing broaching process on the geometric structure of the steel tubes. Burnishing is a plastic surface treatment. Processing tools are hard and smooth surface. Burnishing elements of are ball, roll and disk. Burnishing be flat surfaces, and cylindrical shape. Burnished surfaces are cylindrical outer and inner. Because of the type of the force can be divided into static and dynamic burnishing. Due to the kinematics can be divided into sliding and roller burnishing. Occurrence of moving parts in direct contact with the material qualifies for the group process of burnishing rolling. The sliding burnishing design element property is part of the work surface burnished permanently attached to the handle. Burnishing is used as a finishing strengthens and smoothness, can be realized on the universal machine tools and machining centers, effectively replaces the machining operations such as grinding, reaming, honing and lapping.
Numerical Modelling of the Cooling Ability of Device for the Plates Accelerated Cooling Process
Authors: Laber Konrad Błażej , Knapiński Marcin , Kawałek Anna , Kwapisz Marcin
Published: March 2013

The paper presents results of the numerical modelling of the plates accelerated cooling process after the rolling process. Research were carried out for one of the plate rolling mill technological conditions. Presented in the paper research were done for a few variants for X70 steel grade. As a result of the carried out research temperature distribution on the cross section of the cooled plates for the analyzed variants of the accelerated cooling process were obtain.
The Analysis of Al-Cu Bimetallic Bars Bond Layers Joined by the Explosive Method
Authors: Wąsek Seweryn , Mróz Sebastian , Stradomski Grzegorz , Laber Konrad Błażej
Published: March 2013

The paper presents investigation results for obtaining a semi-finished product in the form of round Al-Cu bimetallic bars by the explosion method. The systems and technological parameters of explosion welding were selected in such a manner as to obtain finished bimetallic bars of an outer diameter of approx. 22 mm and a copper area fraction of the bimetal cross-section of approx. 15 and 30%. In this work was made an analysis of microstructure changes and the microhardness distribution on the cross-sections of the stock materials. There were also made tests of layers connections quality by determining the maximum shear stress on the joint boundary. The results show that the explosive cladding method guarantee a permanent connection of copper layers and aluminum core.
The Analysis of the Impact Relative Rolling Reduction at the Area Connector Bimetallic Plate after the Rolling Process
Authors: Rydz Dariusz , Krakowiak Marlena , Bajor Teresa , Stradomski Grzegorz
Published: March 2013

As part of this work the analysis of the impact relative rolling reduction at the connection area of bimetallic plate after the rolling process was carried out. The rolling process was conducted on samples that have been joined by explosive welding method [1-. The scheme of joining bimetallic plates with use of explosive welding method is shown in fig. 1 [. Geometric and structural design of explosively welded connections depends on the type of welded metal, welding process parameters and the thickness of welded components, the geometry of collision, the type of substrate and surface preparation. Regardless of the type of welded metal, there are three basic types of connections obtained with different parameters of welded plates: flat connections without an intermediate layer of the symmetric deformation of grains, wavy connections and the last one with continuous intermediate layer. This paper presents the analysis of sheet metal connection area after direct double-layer combining by explosive welding method and the next stage of their production - the rolling process. Bimetal plates Al99.8-M1E were rolled with relative rolling reduction ε = 10%, 15% and 20%. The analysis of structural changes was made for both kinds of the samples: after the direct connection and after the annealing operations. In addition to analyzing the results of optical microscopy to present a complete picture of changes in the joints the Vickers micro hardness testing were carried out. Fig. 1. Scheme mergers bimetal plate explosive welding method [5]
The Mechanical Properties and Structure Evolution for High-Manganese TWIP Steel Wires
Authors: Muskalski Zbigniew , Wiewiórowska Sylwia , Pełka Marcin
Published: March 2013

The increasing demand by the automotive industry has resulted in a search for materials of increasingly high mechanical properties and, at the same time, plastic deformability. These requirements are met by AHSS (Advanced High-Strength Steels) multiphase steels. The group of AHSS type steels may include: diphase (DP), TRIP-effect, hot formed (HF) martensitic, plastic formed heat treated (PFHT), and TWIP-effect steels.
Changes in UHMWPE Morphology and Structure after Irradiation with an Electron Beam and Thermal Treatment
Authors: Maszybrocka Joanna , Cybo Jerzy , Barylski Adrian , Czaja Piotr
Published: March 2013

The paper presents changes in UHMWPE morphology and structure induced by exposure to a beam of electrons and thermal processing applied after the modification through irradiation. Two groups of samples were tested: those that underwent modification through irradiation only and those that underwent a sequential process which consisted of radiation modification and thermal processing. The obtained variants were subjected to comprehensive morphological and structural tests, which made it possible to: document changes in the lamellar structure (SEM); determine the content of crystalline phase (DSC); determine the degree and density of crosslinking; state the degree of polymer oxidation (FTIR); examine the influence of the irradiation dose on the intensity of free radicals occurrence (EPR) and to determine the effectiveness of their elimination using recrystallisation in an oxygen-free environment.
Modular System for Testing the Stability and Safety of Specialised Height Rescue Vehicles
Authors: Kozioł Stanisław , Matras Eugeniusz , Zbrowski Andrzej
Published: March 2013

The article describes the structure and the principles of operation of the test system for the investigation of safety of height rescue equipment used by rescue services. The system is composed of a portable computer, data acquisition block and measurement modules equipped with own power supply sources and radio transmission modules. Some of the modules constitute original, mechatronic measurement devices with specific metrological properties. The system is intended particularly for accreditation tests for height rescue equipment used by Fire Brigades.
Destruction of Epoxy Coatings under the Influence of Climatic Factors
Authors: Kotnarowska Danuta
Published: March 2013

The paper presents investigation results of climatic as well as environmental factors influence on surface state of three-layer epoxy coatings. A three-year investigation documented substantial destruction of coating surface layers. In particular, a significant increase of aged coating surface roughness, evaluated on the basis of Ra and Rz parameters, was observed. Studies made with SEM corroborated a delamination as well as pigment and filler crumbling from surface layers of coatings. In the final period of ageing craters and superficial cracks appeared in the coating structure. Destruction of aged coating surfaces contributed to their gloss loss by over 98% (for light incidence angle α = 60o) decreasing in this way coating decorative properties.
Testing of Fibreglass-Metal Laminates in Epoxy Warp Connected by Means of the Adhesive Layer
Authors: Zolkiewski Sławomir
Published: March 2013

The fibre-metal laminate specimens were connected with steel plates by means of the glue joints. The influence of the type of connection on composite mechanical properties (displacement vs. force characteristics) was analyzed. The glue joint between the laminate and the steel plate guarantees even distribution of the displacement during tests. The method of connecting laminates by means of glue joints leads to the connection with the smallest overall dimensions and weight. In the initial research the samples connected by means of different glues were tested.
Generation of Protective Low-Friction Layers in Tribological Processes
Authors: Kotnarowski Andrzej
Published: March 2013

The paper concerns application of tribology achievements in operation of machines kinematic joints. The method of protective layers constituting on rubbing surfaces of kinematic joints elements were presented which minimize adverse effects of friction like motion resistance and wear. A method of protective antiwear and anti friction layers forming on rubbing surfaces of kinematic joints elements at the beginning of exploitation process is proposed.
Studies of the Modelling Accuracy of Steam Turbine Control Systems for Diagnostic Tests of Automatic Synchronizers
Authors: Redlarski Grzegorz , Piechocki Janusz , Dąbkowski Mariusz
Published: March 2013

One of the important factors that affect the reliable operation of the power system and the rapid restitution after disaster is a quick and effective combining synchronous electric power facilities to operate in parallel [. Hence, diagnostics of automatic synchronizers at every stage of their life, from building a prototype, through the whole life, until removing such devices from the operation, is an extremely important and responsible activity. In ordinary practice, this action is performed by dedicated test of mechatronics systems, called simulators [2, , in close to real - or even more restricted - conditions. One of the major limitations in the relevant field undoubtedly concerns the selection of an appropriate structure and implementation of models of the angular velocity control systems involved in the process of connection. These models must be simple enough to allow computation with a frequency of kHz, and, at the same time, developed enough to be able to form diverse and close to real working conditions. For these reasons, classical approach is not possible, allowing the use of well-known Parks model [ of the synchronous generator and the complex - and often nonlinear [. Hence, considered above-mentioned requirements and indicated constraints, to test the automatic synchronizer the designers of mechatronics systems use a number of simplifications during modeling of the angular speed control systems [. However, models are not detailed enough to study the impact of changes in the shape of relevant characteristics under the influence of changes the angle of phase discrepancy in the process of connecting. Hence, this paper presents the results of the research of the currently used method of modeling the most commonly used control systems of angular velocity, in the respective systems.
Wear of Electroplated Tools Used for Flat Grinding of Ceramics
Authors: Deja Mariusz
Published: March 2013

Two methods for the abrasive properties evaluation, based on the image processing, are presented in the paper. Image processing analysis was developed to evaluate quickly the abrasive properties as the tool wears down. The coefficient based on the image brightness was calculated and additional analysis was based on the number of grains located on the active surface of the tool before and after machining. The second method is slower but gives better results especially for reflecting metallic surfaces. The active surfaces of electroplated CBN and diamond tools were analyzed. The practical time of electroplated tools' usage can be predicted with proposed methods.
Teaching in Automatic Control and Robotics Discipline in Terms of Changes in Higher Education System: Experiences and Suggestions
Authors: Podsędkowski Leszek , Kobierska Agnieszka , Sikora Małgorzata , Fracczak Lukasz , Niewola Adam , Zawierucha Marcin , Żak Paweł
Published: March 2013

This paper is an attempt to outline certain phenomena conditioning tertiary education: mental changes of the youth, legal changes in higher education and changes in demands and profile of the industry. In the paper the experiences of making changes in the studies program of Automatic Control and Robotics discipline at Faculty of Mechanical Engineering of Technical University of Lodz were presented. Particular emphasis has been placed on demonstrating how to use the laboratory background in order to meet the needs of the industry. A proposal showing a better method of implementing the studies program in the new reality has been presented. The authors have also presented their own reflections on the advantages and disadvantages coming from the new system.
The Influence of Diagnostic Signal Measurement Period on Blades Technical Condition Images Determined from Phase Shift Difference
Authors: Grądzki Rafał
Published: March 2013

In the article, new method of monitoring of rotor machine blades technical condition is presented. This method is based on diagnostic model φT12T01 [ which uses phase shift difference of signal fragments resulting from blade operation y (t) during blade recession from sensor and during approach of blade tip towards the sensor as well as signal of its environment x (t) described using proper distribution. The assumed diagnostic model also indirectly includes actual blade environment x (t) without necessity of its measurement [3,. Contactless inductive sensor constantly measures the signal of operating blade transition below the sensor. However, several difficulties with determination of last sample of blade receding from the sensor with first sample of blade approaching the sensor exist. Additionally the problem occurs with measurement of space between blades. So far, the case was solved by use 90% of this space range (in order to eliminate the overlapping of adjacent blades signals). Hence the problem of assessment of measurement period breadth on obtained models (images) of blades. The possibility of blade damage detection by analysis of less than 90% signal course was tested.
Evaluation of Speech Intelligibility and Sound Localization Abilities With Hearing Aids Using Binaural Wireless Technology
Authors: Ibrahim Iman , Parsa Vijay , Macpherson Ewan , Cheesman Margaret
Published: March 2013

Wireless synchronization of the digital signal processing (DSP) features between two hearing aids in a bilateral hearing aid fitting is a fairly new technology. This technology is expected to preserve the differences in time and intensity between the two ears by co-ordinating the bilateral DSP features such as multichannel compression, noise reduction, and adaptive directionality. The purpose of this study was to evaluate the benefits of wireless communication as implemented in two commercially available hearing aids. More specifically, this study measured speech intelligibility and sound localization abilities of normal hearing and hearing impaired listeners using bilateral hearing aids with wireless synchronization of multichannel Wide Dynamic Range Compression (WDRC). Twenty subjects participated; 8 had normal hearing and 12 had bilaterally symmetrical sensorineural hearing loss. Each individual completed the Hearing in Noise Test (HINT) and a sound localization test with two types of stimuli. No specific benefit from wireless WDRC synchronization was observed for the HINT; however, hearing impaired listeners had better localization with the wireless synchronization. Binaural wireless technology in hearing aids may improve localization abilities although the possible effect appears to be small at the initial fitting. With adaptation, the hearing aids with synchronized signal processing may lead to an improvement in localization and speech intelligibility. Further research is required to demonstrate the effect of adaptation to the hearing aids with synchronized signal processing on different aspects of auditory performance.
Invasive Pneumococcal Infection Despite 7-Valent Conjugated Vaccine
Authors: Joye Sebastien , Gao Anja , Kayemba-Kay's Simon , Cotting Jacques , Perez Marie-Hélène
Published: March 2013

Despite good cover with 7-valent vaccination, invasive pneumococcal infections may still be misdiagnosed and may lead to lifethreatening situations or death in young children. New serotypes are emerging and, therefore, clinicians must keep a high level of suspicion in young children regardless of their vaccination status. We report three cases of invasive pneumococcal infection due to new serotypes not covered by the 7-valent conjugated vaccine, two of which led children to death.
Retropancreatic Teratoma with Intra-Thoracic Extension
Authors: Bakhshi Girish , Wankhede Kishor , Bhandarwar Ajay , Tayde Mukund , Shenoy Sachin , Gore Sandeep
Published: March 2013

Primary retroperitoneal teratoma is a rare entity in adults. We present a case of 23-yearsold female who presented with complaint of abdominal pain in left upper quadrant. Computed tomography scan revealed a retroperitoneal retropancreatic teratoma near celiac axis with intra thoracic extension. Laparotomy with tumor resection was done. The case report is interesting for intra thoracic extension of retropancreatic teratoma.
Elucidating potentially significant genomic regions involved in the initiation and progression of undifferentiated pleomorphic sarcoma
Authors: Kurywchak Paul , Kiefer Jeff , Lenkiewicz Elizabeth , Evers Lisa , Holley Tara , Barrett Michael , Weiss Glen J.
Published: March 2013

Sarcomas are cancers that arise in soft tissues or bone and make up a small percentage of malignancies. In an effort to identify potential genetic targets for therapy, this study explores the genomic landscape of a metastatic undifferentiated pleomorphic sarcoma (UPS) with spindle cell morphology. Thick sections (50 µm) of formalin-fixed, paraffin-embedded tissue from a primary, recurrent, and metastatic tumor were collected and processed from a single patient for DNA content-based flow-sorting and analyses. Nuclei of diploid and aneuploid populations were sorted from the malignant tissues and their genomes interrogated with array comparative genomic hybridization. The third sample was highly degraded and did not contain any intact ploidy peaks in our flow assays. A 2.5N aneuploid population was identified in the primary and recurrent sample. We detected a series of shared and unique genomic aberrations in the sorted aneuploid populations. The patterns of aberrations suggest that two similar but independent clonal populations arose during the clinical history of this rare tumor. None of these aberrations were detected in the matching sorted diploid samples. The targeted regions of interest might play a role in UPS and may lead to clinical significance with further investigation.
Early Clinical Outcomes in Midline Sinonasal Cancers treated with Helical Tomotherapy-based Image-guided Intensity-modulated Radiation Therapy
Authors: Nair Deepa , Murthy Vedang , Budrukkar Ashwini , Agarwal Jaiprakash , Tejpal Gupta , Ghosh-Laskar Sarbani , Pai Prathamesh , Wadasadawala Tabassum , Phurailatpam Reena , Paul Siji Nojin
Published: March 2013

Introduction

Sinonasal cancers have variable biological behavior and outcomes. The physical proximity of several critical structures renders radiotherapy challenging for these cancers.

Purpose

To report our early experience of helical tomotherapy (HT)-based image-guided intensity-modulated radiation therapy (IMRT) in midline sinonasal cancers.

Materials and methods

Patients with midline sinonasal cancers were accrued on a prospective generic protocol of HT-based IMRT. HT plans were evaluated using standardized indices. All patients were followed up clinicoradiologically. Local control was defined as absence of failure (recurrence/ progression) in the tumor bed, whereas distant disease control was defined as absence of distant metastases. All time-to-event data was analyzed using Kaplan-Meier methods.

Results

Ten patients with a median age of 42 years (range: 29-62 years) were included. HT was able to achieve excellent target volume coverage, good high-dose conformality with exquisite sparing of organs at risk. The acute toxicity of HT was generally mild and self-limiting. Seven patients experienced acute grade I-II ocular toxicity that responded to topical steroids, while one patient developed grade III conjunctivitis. The same patient later developed bilateral cataract necessitating extraction (late grade III ocular toxicity). No patient experienced dry-eye syndrome, corneal opacity or blindness. With a median follow-up of 27 months (interquartile range: 13-35 months), the 3-year Kaplan-Meier estimate of local progression-free survival, distant metastases-free survival, disease-free survival and overall survival was 59.3, 90, 53.3 and 90% respectively.

Conclusion

HT-based image-guided IMRT for midline sinonasal cancers achieves good high-dose conformality and is associated with mild, self-limiting acute ocular toxicity, minimal late morbidity with acceptable disease control.

How to cite this article

Gupta T, Wadasadawala T, Phurailatpam R, Paul SN, Murthy V, Budrukkar A, Ghosh-Laskar S, Nair D, Pai P, Chaturvedi P, Agarwal JP. Early Clinical Outcomes in Midline Sinonasal Cancers treated with Helical Tomotherapy-based Image-guided Intensity-modulated Radiation Therapy. Int J Head and Neck Surg 2013;4(1): 6-12.
Head and Neck Cancer Burden in India
Authors: Kulkarni Manik Rao
Published: March 2013

Introduction

Head and neck cancer in India has distinct demographic profile, risks factors, food habits, and personal and family history. They are emerging as major public health problems in India, which are lifestyle related, have a lengthy latent period and need dedicated infrastructure and human resource for treatment. Need based and coordinated research for understanding the threats to the nation from chronic diseases such as head and neck cancers and ways to defy such threats will assume increasing importance.

Magnitude of problem in India

Overall, 57.5% of global head and neck cancers occur in Asia especially in India. Head and neck cancers in India accounted for 30% of all cancers. In India, 60 to 80% of patients present with advanced disease as compared to 40% in developed countries. A slow decline in the incidence of most of head and neck cancers has been documented in India.

Management of head and neck cancers in India

The problem of managing head and neck cancers in India is somewhat different, as compared to the west. The major shortcoming is to cope up, with the loss to follow-up, which makes the task of conducting and reporting the end results of clinical trials awfully difficult.

Conclusion

The highest priority for cancer control should be given to the burden of head and neck cancer in India. The emphasis should be on preventing the onset and detecting the disease at an early stage. In developing countries like India, implementing cancer control activities has to be prioritized, making optimal use of limited resources to deliver the utmost benefit to the largest number of people.

How to cite this article

Kulkarni MR. Head and Neck Cancer Burden in India. Int J Head and Neck Surg 2013;4(1):29-35.
Advanced Case of Invasive Basal Cell Carcinoma with Extensive Ocular Myiasis
Authors: Gupta Sumit , Naik Sudhir , Halkud Rajshekar , Nanjundappa A
Published: March 2013

Background

Ocular myiasis or ophthalmomyiasis means the infestation of the eye on a background of foul smelling skin infection or advanced case of skin cancers. Older people, immunocompromised patients with orbital carcinomas, diabetics and patients on immunosuppressive therapy, poor environmental sanitation and personal hygiene are prone for this infestation.

Case report

A 72-year-old female reported to us with extensive myiasis of the right eye. Lesion of 4 × 4 cm at the medial canthus and the right maxillary region with the right nasal dorsum was infested with maggots. All the larvae were removed with forceps and the wound debrided.

Intervention

The larvae were present for a week and on healing the wound was evaluated with computed tomographic (CT) scan paranasal sinuses with axial and coronal section. As no bony erosion and intracranial extension was noted hence considering the age and diabetic status surgery was not contemplated and the lesion was irradiated.

Conclusion

Ocular myiasis is a rare disease, accompanied by marked inflammatory reactions and secondary bacterial infections with massive destruction and life-threatening consequences, such as intracranial invasion. Prompt management with debridement and radical antibacterial therapy is essential.

How to cite this article

Naik SM, Nanjundappa A, Halkud R, Gupta S. Advanced Case of Invasive Basal Cell Carcinoma with Extensive Ocular Myiasis. Int J Head and Neck Surg 2013;4(1):36-40.
Metastatic Nasopharyngeal Carcinoma Simulating a Schwannoma of the Vagus Nerve
Authors: Pascual-Gallego Maria , Moreno-Gutierrez Angela , Gutierrez-Gonzalez Raquel , Rodriguez-Boto Gregorio
Published: March 2013

Schwannomas of the vagus nerve are extremely rare neoplasms of difficult diagnosis and with a challenging surgical excision. We report a patient with a parapharyngeal mass radiologically indistinguishable from a schwannoma that was finally diagnosed as metastatic nasopharyngeal carcinoma.

How to cite this article

Pascual-Gallego M, Moreno-Gutierrez A, Gutierrez-Gonzalez R, Rodriguez-Boto G. Metastatic Nasopharyngeal Carcinoma Simulating a Schwannoma of the Vagus Nerve. Int J Head and Neck Surg 2013;4(1):44-46.
Regional Grafts for Closure of Postsurgical Defect in Anterior Maxilla: Versatility of Chin Graft and Local Rotational Flap
Authors: Manekar Varsha Sunil
Published: March 2013

The management of postsurgical defect is a challenge for the maxillofacial surgeon. With the success of various autogenous grafts and surgical flaps the reconstruction surgery creates definitive results. This article is a case report of reconstruction of osseous defect and closure of soft tissue fenestration in the right anterior maxilla. An autogenous corticocancellous graft from the mandibular symphysis is used for reconstruction of the osseous defect of around 15 × 15 mm. The mucosal fenestration of around 10 × 10 mm is closed by rotational flap based in the labial sulcus. The defect and the donor site healed uneventfully. Both osseous and mucosal defect healed with esthetic results. Thus, the regional flaps prove the versatility by convenience of graft taking, no donor site morbidity and biological resemblance of tissues.

How to cite this article

Manekar VS. Regional Grafts for Closure of Postsurgical Defect in Anterior Maxilla: Versatility of Chin Graft and Local Rotational Flap. Int J Head and Neck Surg 2013;4(1):47-50.
Comparing the Efficacy of Urinary hCG vs Recombinant hCG for Final Maturation of Oocyte in GnRH Antagonist IVF/ICSI Cycle
Authors: Srinivas MS , Sidhmalswamy G Ashwini , Dipika K , Anu K , Mekhala D
Published: March 2013

Aims and objectives

To compare the efficacy of urinary human chorionic gonadotropin (uhCG)vsrecombinant human chorionic gonadotropin (rhCG) for triggering ovulation in gonadotropinreleasing hormone (GnRH) antagonistin vitrofertilization (IVF) cycle.

Materials and methods

Two hundred patients who underwent GnRH antagonist IVF/ICSI cycles were analyzed, 100 of them received recombinant hCG 250 μg (injection overtrelle) and another group of 100 received urinary hCG (injection ovutrig) either 5000 IU or 10,000 IU for final oocyte maturation and ovulation trigger. The primary outcome measured was total oocytes retrieved and the secondary outcome measured 09 was the maturity rate fertilization rate, cleavage rate and clinical pregnancy rates were also compared.

Results

Age, day 2 follicle stimulating hormone (FSH) and total dose of rFSH were comparable between the groups. There were no significant differences between the groups in terms of the mean number of oocytes retrieved per follicle (uhCG; 12.5, rhCG; 12.09, p-value-0.6698). Similarly, there was statistically no difference in any of the other parameters studied between the two groups. That is number of mature oocytes, number of fertilized oocytes and number of cleaved oocytes, as the p-value was not significant. The clinical pregnancy rate was somewhat higher in the uhCG group but was not statistically significant. Both treatments were well tolerated and there was no significant side effects for either drug.

Conclusion

There is no difference in clinical outcomes between urinary and recombinant hCG for induction of final oocyte maturation. Additional factors, including the cost, drug availability and ease of administration, should be considered, when choosing gonadotropin type.

How to cite this article

Sidhmalswamy GA, Srinivas MS, Dipika K, Anu K, Rao KA, Mekhala D. Comparing the Efficacy of Urinary hCG vs Recombinant hCG for Final Maturation of Oocyte in GnRH Antagonist IVF/ICSI Cycle. Int J Infertility Fetal Med 2012;3(3):92-96.