91 research outputs found
Research Notes : Poland : Interdependences between some traits in early hybrid genera-tions (F2-F4) of soybean
The existence of an interdependence between some important traits of soy-bean is of great significance for its breeding. In rather cool climate (Poland) interdependences between developmental traits and yield structure elements affect the possibility of fast creation and introduction of new, well-adapted and efficient cultivars into agricul-tural practice. Estimation of phenotypic correlations of 11 traits was the subject of this paper
Research Notes : Poland : Performance of some important characters of hybrid soybean (F1) in a cool climate
Obtaining intervarietal hybrids of Glycine max (L.) Merrill in a cool climate such as in Poland (latitude above 50°N) is one of the most important problems for development and introduction of original cultivars of this species. In 1977, hybrid soybean seeds were obtained for the first time in our Academy through field crossing of various forms (cultivars and PI\u27s). Charac-teristics of some important traits of F1 plants in comparison with their par-ental forms were the subject of this paper
Elastyczny taping – przegląd metod bazujących na oddziaływaniu elastycznego plastra
Methods of physiotherapy based on work with a flexible patch (taping) have became more and more popular in the recent years. Thanks to a wide range of applications and a small number of contraindications, flexible taping quickly found usage in sports and clinical physiotherapy. The most common methods in Poland which are based on work with elastic tapes are: Kinesio Taping, Taping Kinesiology and Medical Taping (medical taping).The purpose of the study is to present methods based on work with the flexible patch and indication of their interrelationships. Due to the fact that all methods based on the work with a flexible patch derive from Kinesio Taping method, many common elements can be observed. All Kinesio Taping, Kinesiology Taping and Medical Taping are supporting patch applications on myofascial chains theory and tensegrity theory. However, the therapy is based on a flexible patch which has the parameters similar to parameters of human skin.Unfortunately, there is still no comprehensive research, supported by clinical studies explaining accurately how the mechanics of effects arose after the treatment works and what its duration is. It is therefore necessary to perform numerous studies using various measuring instruments, which respond to constantly asked questions.W ostatnich latach metody fizjoterapeutyczne bazujące na wykorzystywaniu elastycznego plastra (tapingu) bardzo zyskały na popularności. Dzięki szerokiemu spektrum zastosowań oraz niewielkiej liczbie przeciwwskazań elastyczny taping szybko znalazł zastosowanie w sporcie i fizjoterapii klinicznej. W Polsce najbardziej powszechne metody bazujące na wykorzystaniu elastycznej taśmy to: Kinesio Taping, Kinesiology Taping i Medical Taping (taping medyczny).Celem pracy jest przedstawienie powyższych metod bazujących na wykorzystaniu elastycznego plastra oraz wskazanie ich wzajemnych powiązań.Biorąc pod uwagę fakt, iż wszystkie metody bazujące na pracy z elastycznym plastrem wywodzą się z metody Kinesio Taping, można dopatrzyć się w nich wielu elementów wspólnych. Zarówno Kinesio Taping Kinesiology Taping jak i Medical Taping opierają aplikacje plastra o teorie łańcuchów mięśniowo-powięziowych i teorię tensegracji, a podstawą terapii jest elastyczny plaster o parametrach zbliżonych do parametrów ludzkiej skóry. Niestety w dalszym ciągu brak jest kompleksowych opracowań, popartych badaniami klinicznymi, wyjaśniających dokładny mechanizm działania powstałych efektów po terapii oraz ich czas trwania. Niezbędne są zatem liczne badania z zastosowaniem różnego rodzaju aparatury pomiarowej, które odpowiedzą na wciąż stawiane pytania
Experimental analysis of the state of stress in a steel – titanium perforated plate loaded with concentrated force
The paper presents an experimental analysis of the state of stress, free supported on the edge of a steel – titanium circular perforated plate loaded with a centrally concentrated force, created in the technological process of explosion welding. For this purpose, a special test stand was designed and a methodology for testing the perforated plate was developed. Resistance strain gauges were used to measure the state of strain. The load was applied in the center of the plate to a pressure stamp. As a result of the research, the values of radial, circumferential and equivalent von Mises stress were obtained as a function of the radius of the plate perforation circle and its load. The stress distribution topography revealed the zones of maximum stress of the steel – titanium perforated plate. The proposed method of experimental research can be used by engineers to verify the state of stress, e.g. in the designed tube sheet walls of reactors for ammonia synthesis
Influence of the applied layer on the state of stress in a bimetallic perforated plate under two load variants
The paper presents the results of the analysis of the influence of the applied plate layer on the state of stress in the bimetallic perforated plate. The finite element method ANSYS program was used for numerical calculations. The paper presents the results of stress tests for a single-layer clad plate made of S355J2 steel and a bimetallic perforated plate consisting of layers made of S355J2 steel and titanium. In addition, the study presents the results of the research on the influence of the method of loading, i.e. the concentrated force P in the geometric center of the plate and the external pressure q on the entire surface of the plate, and the method of support, i.e. free support and fixed, on the location of stress concentration zones in the bimetallic circular perforated plate. It has been shown that the presence of a perforated layer in the plate reduces the value of the equivalent von Mises stress by a minimum of approximately 30% in the base (steel) layer
Research of stress distribution in the cross-section of a bimetallic perforated plate perpendicularly loaded with concentrated force
The paper presents the stress distribution along the plate thickness in a bimetallic steel – titanium circular, axially symmetrical perforated plate produced in the technological process of explosion welding. The steel layer is the layer that transfers the load in the plate, while the titanium layer is used to improve the properties of the plate, e.g. corrosion resistance, thermal transmittance, etc. in the plate. Two cases of fastening were considered, i.e. a freely supported and fixed plate. Such plates are used in various engineering structures, e.g. simply supported plates can be used in loose material screens, while plates are fixed in heat exchangers. The load was assumed as a concentrated force applied perpendicularly to the plate surface. The results obtained numerically using the finite element method were compared with the results calculated according to the analytical equations. It has been shown that the difference in the results of equivalent von Mises stress calculations does not exceed 13%. The research results presented in the paper can be used by engineers to design bimetallic perforated plates perpendicularly loaded to their surface
Dynamic model of a harmonic drive in a toothed gear transmission system
The present paper discusses certain aspects of dynamic modeling of the harmonic drive. In particular, a new original dynamic model of a harmonic drive has been proposed for a power transmission system. The model takes account of nonlinear changes in stiffness, as well as damping. The proposed model of a harmonic drive in the power transmission system is investigated in the Matlab-Simulink environment. Utilization of the identified, developed dynamic model will allow to expand the knowledge about torsional vibration which are present in power transmission systems equipped with harmonic drive as well as it will contribute to a reduction of expenses connected with performing costly experimental tests
Non-conventional suspension systems in heavy special-purpose trucks
The paper provides a discussion on various solutions used in suspension systems of special-purpose vehicles. On account of its low cost and design simplicity owing to which it is commonly applied, the mechanical dependent suspension system based on leaf springs has been described. The paper also addresses non-conventional pneumatic and hydropneumatic systems based on gas springs, allowing for selected suspension parameters to be controlled, including clearance
Analysis of the chassis design for a high mobility wheel platform
This paper provides an analysis of a solution proposed for the design of the chassis of a special-purpose vehicle’s mobile platform using an example of the high mobility wheel platform (KPWM) manufactured by the company Szczęśniak Pojazdy Specjalne. The basic requirements pertaining to vehicle chassis are related to requirements concerning mechanical strength and lightness of structures, being difficult to satisfy at the same time. The suspension system used in the high mobility wheel platform in question represents a typical design, comprising a frame made of high-strength steel and based on stringers. The high mobility wheel platform’s suspension system uses reinforced parabolic leaf springs and half-elliptic springs as the elastic elements, whereas shock absorbers and stabilisers as the damping and propelling elements, aimed to reduce tilts of the vehicle body while driving in a curvilinear track. By shifting the front driving axle towards the front vehicle section, a higher approach angle could be obtained. On account of difficult operating conditions and for off-road driving purposes, specific solutions have been applied to protect the vehicle chassis against damage when moving in difficult terrain. Moreover, bearing in mind the vehicle’s intended use in military operations, where unplanned repairs of chassis components must often be conducted in the field, the designers have taken the necessity of using a very limited set of tools into account
Application of the discrete wavelet transform and probabilistic neural networks in IC engine fault diagnostics
Around the world are continued attempts to use the vibroacoustic phenomena for purposes of diagnosis of machine condition. Particularly important becomes non-invasive methods including methods based on vibration and acoustic signals. Vibroacoustic phenomena, which relates to the working of technical objects, includes all necessary information connected with the technical condition. The biggest difficulty is the transformation of registered vibroacoustic signals and creation on their basic measures, which will be non-sensitive to any type of interference occurring during the operation of objects and recording signals. To the group of technical objects, for which are already conducted numerous studies all over the world, connected with use of vibroacoustic phenomena for diagnostic purposes which relates to the automotive drive systems, including combustion engines. Combustion engines during its working generate a whole range of vibroacoustic phenomena bringing information on the proper operation of the engine, as well as on condition of each of its elements. In a combustion engine, there are many sources of vibroacoustic phenomena, which contributes to the disruption of diagnostic information. The development of appropriate methods for vibroacoustic signal processing and complete diagnostic systems may allow future extension of the on-board diagnostics OBD system – currently in used cars. The most interesting would be the development of complex system for diagnosing the condition of the individual elements of the car engine operating by basing on information from vibroacoustic signals. In this article are shown results of research, which aim is to diagnose damages of mechanical elements of car combustion engine using vibration signals and artificial neural networks
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