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Investigations of material parameters within the system Al, Al₂O₃, Ta, Ta₂O₅ and TaO_xN_1‐x are presented. This combination is characteristic when using Al sheet for production of substrates including electronic interconnections, vias and resistive groups. They can serve for MCMs due to the specific features of Al. The technological process includes first electrochemical oxidation of Al‐sheet as base isolation layer Al₂O₃ (50‐70μm). This process is followed by vacuum deposition of relatively thick layers of Al (2‐5μm). Each layer is then processed by lithographic methods followed by selective electro‐chemical oxidation as a help process for structuring. The development of this combined structuring method allows the simultaneous achievement of interconnections (Al) and isolation (Al₂O₃) levels with least size up to 50μm. The importance of the method consists of a vertical combination of several conductive layers of Al structured as described above, “burying” the interconnections in the insulating Al₂O₃ films. All necessary combinations and configurations of different kinds of microstrip lines are possible. The dielectric characteristics of Al₂O₃, achieved through the above mentioned method, can be changed in accordance with the parameters of the technological steps and filling of the porous structure. Thus some interesting high frequency features of microstrips are obtained. Extra advantage is the ability of combination of conductive Al layers with other types of such layers as tantalum (Ta). With Ta can be achieved other permittivity constants of the insulation layers and in combination with TaO_xN_1‐x intermediate planes of resistive groups are developed. The measurement of the stripline parameters is done by microwave technics, because the desired application of the substrates is for high‐speed digital signals in the GHz range.

In this paper we present recent studies on the electrochemical migration processes in Ag thin film parallel microstrip lines in MCM(D) structures. The basic concept is applying accelerated local drop‐test of water solutions onto the surface of two adjacent lines, under a given voltage potential. These operational conditions are often met in the interconnection line buses, placed in the top assembly level of multilayered hybrid structures. The subject of investigations are MCM(D) developed on Al‐sheet carrier with internal conducting and isolating layers, produced through unique selective electrochemical anodization of Al and Ta. This technology process also enables the creation of embedded R and C passive components on the base of TaO_xN_1‐x and Ta₂O₅ (or Al₂O₃) respectively. We propose an electrochemical deposition of Ag/Sb alloys on the surface of Al interconnection lines and contact pads to ease the bondability and solderability in chip mounting procedures. The artificially created silver migrated defects and partial shorts are investigated through the high frequency method of coupled transmission lines in order to eliminate the errors and insufficient validity of DC direct measurements.

The purpose of this paper is to solve the problem of joint bearings that cannot work in high temperature because of their high frictional coefficients.

Two methods of inlaying graphites and liquid spraying of MoS₂ are designed. The arrangement of graphites is shown and its frictional coefficients (COFs) are discussed. MoS₂ coating is deposited by liquid spraying. The ingredients of liquid spraying of MoS₂ are illustrated. Stresses, structure deformations and fatigue life are analyzed by finite element analysis.

Results show that both two designed methods can decrease COFs effectively. All stresses are in the limit of the maximum permissible stresses. The new designed bearings can be safety worked in sealed and high temperature environment which are proved by fatigue analyses.

Two new designs can help joint bearings work in nuclear plants because of their low COFs and litter wear. The new designs can improve bearings life.

Two methods of decreasing COFs of joint bearings are designed in this paper. The technologies are illustrated. The proper scopes of applications of two designed methods are discussed.

Pervasive health-care computing applications in medical field provide better diagnosis of various organs such as brain, spinal card, heart, lungs and so on. The purpose of this study is to find brain tumor diagnosis using Machine learning (ML) and Deep Learning(DL) techniques. The brain diagnosis process is an important task to medical research which is the most prominent step for providing the treatment to patient. Therefore, it is important to have high accuracy of diagnosis rate so that patients easily get treatment from medical consult. There are many earlier investigations on this research work to diagnose brain diseases. Moreover, it is necessary to improve the performance measures using deep and ML approaches.

In this paper, various brain disorders diagnosis applications are differentiated through following implemented techniques. These techniques are computed through segment and classify the brain magnetic resonance imaging or computerized tomography images clearly. The adaptive median, convolution neural network, gradient boosting machine learning (GBML) and improved support vector machine health-care applications are the advance methods used to extract the hidden features and providing the medical information for diagnosis. The proposed design is implemented on Python 3.7.8 software for simulation analysis.

This research is getting more help for investigators, diagnosis centers and doctors. In each and every model, performance measures are to be taken for estimating the application performance. The measures such as accuracy, sensitivity, recall, F1 score, peak-to-signal noise ratio and correlation coefficient have been estimated using proposed methodology. moreover these metrics are providing high improvement compared to earlier models.

The implemented deep and ML designs get outperformance the methodologies and proving good application successive score.

The purpose of this paper is to determine and compare the tribological characteristics (weight wear and friction moment) of a friction couple C45/C330 at running‐in with motor oil SAE 30 and different friction modifiers of copper oleate and zinc oleate.

Friction couples are tested using the model “roller‐sector” and they are lubricated with oil SAE 30 and two other samples of SAE 30 containing 0.6 per cent copper oleate and 0.6 per cent zinc oleate, respectively. Graphic dependencies are drawn for the weight wear of the sectors, rollers and couples; as well as for the running‐in moment, the friction moments at the end of the loading and at the end of the test.

The weight wear, running‐in moment and friction moments are evaluated for friction with SAE 30 as reference and oils containing copper oleate and zinc oleate as friction modifiers. The best performing material is the oil with zinc oleate.

From a practical point of view this paper offers a new idea about a friction modifier – zinc oleate. Data for tribological characteristics and suitable concentration in the oil composition are given in the paper.

The paper aims to present a new friction modifier (mixture of zinc and copper oleates) proper for industrial running-in of repaired engines.

The method of comparison was used for testing the offered friction modifier, a market product “Renom Engine” and a blank sample of motor oil as an etalon. Running-in time has been established. The mechanical losses change and the relevant coefficients have been determined. Data of the bearings wear have been included.

The benefit of the metal oleates and Renom Engine usage as friction modifiers has been proved. Time for industrial cold running-in of repaired engines decreases by around 20 per cent when friction modifiers are used in comparison with the etalon oil. The coefficient of the mechanical losses reduction at running-in with friction modifiers is higher than the coefficient for the etalon oil. The higher coefficient values indicate that the running-in of the working surfaces occurs more intensively and for a shorter period of time. Lower wear of the bearings is combined with smaller roughness of the friction surface, which secures higher quality of the surfaces run-in with the friction modifiers and greater capacity by around 30 per cent.

This study introduces a new friction modifier for industrial running-in of repaired engines. It would be of interest to the customers and manufacturers of oil additives.

To evaluate the efficiency of complex esters as plasticizers in polyvinyl chloride plastisols and plasticates.

Several poly(vinyl chloride) plastisols and plasticates were prepared with standard phthalate plasticizers and complex esters and were characterised using standard and laboratory methods.

The use of mixtures of three new CE with standard phthalate plasticizers increased the physical, mechanical and electric characteristics of the resulting PVCPs and PVCPl.

The use of three new CE, obtained by esterification of dicarboxylic acids (adipic, sebacic, pelargonic), poly(ethylene glycol) and i‐octanole, as plasticizers of poly(vinyl chloride) plastisols and plasticates was investigated. The use of CE based on other organic acids could be explored.

The results confirmed the efficiency of plasticization of PVC by CE. Such a finding has significant industrial implication.

Several findings are original and are of importance to relevant industry. The new CE with high molecular weights were effective plasticizers of PVC. The efficiency of the plasticizers depended on their chemical structure. The molecular weight of the CE had no influence on the compatibility of plasticizers and other components of the PVC plastisols and plasticates.

This paper seeks to investigate the influence of chemical structure of ester basestock (trimethylolpropane pelargonate) on the viscosity characteristics of formulations obtained and the operating mechanism of two widely used viscosity index improvers – poly(butadiene‐styrene) and poly(alkyl methacrylate).

Oil formulations of trimethylolpropane pelargonate and poly(butadiene‐styrene)/poly(alkyl methacrylate) as viscosity index improvers are prepared. Their kinematic viscosity at different temperatures is measured. Relative, intrinsic and characteristic viscosities are calculated from the experimental data.

The thickening ability of linear polymers from butadiene‐styrene and alkyl methacrylate in a synthetic oil of ester type (trimethylolpropane pelargonate) is clarified. The conformation of these polymers is studied. Results of comparative tests about the influence of the type of polymer and solvent on characteristic and intrinsic viscosity are presented. It has been established that with the increasing of temperature the quality of used synthetic oil decreased and the characteristic viscosity decreased for both polymers. At lower temperatures the intermolecular interaction between the polymeric macromolecules becomes bigger than their interaction with the molecules of solvent. Molecule associates have been possibly formed at low temperature. These associates increase the viscosity of solutions and this increase is bigger at low temperatures in comparison with high temperatures.

Viscosity index improvement of poly(butadiene‐styrene) and poly(alkyl methacrylate) is determined. The information about concentrations and viscosity is of practical interest.

The combination of these synthetic basestock and viscosity index improvers is a new one. The data obtained may have value for the oil production.

The aim of this study is the synthesis and characterization of motor and hydraulic oils based on complex esters of dicarboxylic acids and polyol esters. The esters have been prepared by polyesterification of adipic or sebacic acids with polyethylene glycol and by subsequent reaction with 2‐ethylhexanol using a new high active catalyst tetraoktyltitanate (TOT)‐TlCl. The synthesis of pentaerythritol esters of monocarboxylic acids has also been undertaken in the presence of the same catalyst. The catalyst reduces the time and temperature required for the reaction to produce esters with characteristics of standard motor and hydraulic oils.

Recent progress in the investigation of the material parameters of Al/Al₂O₃systems leads to an increase in the possibilities for using embedded TaO_XN_1‐X layers. The use of Al‐sheets as mechanical strength carriers in combination with vacuum‐deposited Al‐layers and electrochemically anodized Al₂O₃ structure requires study. This was found to create a periodic multilayer Al/Al₂O₃ structure. The material qualities of this system allow optimization in order to achieve high speed data processing and signal propagation. The existing studies using Al and Ta combination as well as the high resistance qualities of the modified TaO_XN_1‐X layers have shown satisfactory results. It can be concluded that the development of this new layer combination is possible in the multilayer carrier structures. Some preliminary research studies show a proper adhesion and satisfactory characteristics of the two integrated resistive planes in the multilayer combination Al/Al₂O₃//TaO_XN_1‐X/Ta₂O₅/Al.