Compression Force Values Research Articles

Efficacy of Contrast Medium-assisted Imaging in Diagnosing Cracked Tooth

Introduction: This experimental study aimed to evaluate the efficacy of contrast medium-aided intraoral periapical radiographic imaging in the detection of cracked teeth and to determine optimal in-vitro compression force for crack detection. Methods: 27 extracted human lower premolar teeth were randomly divided into two groups: the control group, which was imaged using the conventional radiography and the experimental group which was imaged using a contrast medium (Iopamidol®). Both group were examined by transillumination to confirm the presence of a crack prior to imaging. A compression test using a Universal Testing Machine was used to induce the crack. Two dental clinicians blinded to the imaging technique evaluated the images and determined the presence or absence of cracks. Results: The force needed to produce a superficial crack ranges from 200N to 500N with a median compression force of 400N. The range of force to produce partial crack was 200N to 550N with the median force slightly higher than superficial crack which is 435N. The force to produce dentinal fracture ranges from 300N to 1100N with the highest median of 525N. The results showed that there were no visible cracks were detected in IOPA with/without contrast medium. Conclusions: The study did not find contrast-enhance IOPA to be effective in detecting cracks, but the study did establish the optimal median compression force values for inducing cracks which is between 400N to 525N. IOPA with contrast medium is not an effective diagnostic tool for cracked teeth compared to transillumination.

Triad resonance of flexural gravity waves in the presence of shear current with constant vorticity

This study examines the formation of triads of flexural gravity wave in a homogeneous fluid within the context of blocking dynamics due to the presence of shear current. This study will enable us to understand the distribution of wave energy on an ice-covered sea surface. New classes of triads for flexural gravity waves are introduced depending on the direction of wave propagation with following and opposing currents. The study reveals that triad formation occurs due to the interaction of flexural gravity waves irrespective of the presence of compression and current, which has not been found in the case of free surface gravity waves. In addition, at most, three triads are formed in the case of flexural gravity waves in the presence of following and opposing currents prior to the threshold of blocking. In contrast, at least three triads are formed for any frequency within the primary and secondary blocking limits for certain values of compressive force and current speed. On the other hand, 11 triads are formed in the presence of uniform current speed as well as in the case of linear shear current with constant vorticity for a certain frequency within the blocking limit for higher values of compressive force and current speed.

Finite Element Simulation of Compressing an Additively Manufactured Mesostructure

Abstract Numerical modeling is a useful approach for answering research questions that are either difficult or inefficient to answer experimentally. The goal of this study was to develop a validated numerical model of a stereolithography (SLA) manufactured mesostructure to predict compression behavior. A three-dimensional (3D) model was created for an 80 × 80 × 20 mm compression block. ANSYS was used to simulate compression testing of this structure. The lower plate of the structure was fixed while a vertical displacement was prescribed on the upper plate. The base material was modeled using a linearly elastic, isotropic material derived from Young's modulus (E), Poisson's ratio, and the ultimate tensile strength. The base material was varied to represent three different SLA polymers from Formlabs (i.e., three different models of the same geometrical structure). The shape of the force–displacement curves and compression force values agreed well between the model and previously collected experimental data. However, this agreement was limited to stiffer materials and only up to 10 mm of compression. This may be where the structure shifts from elastic to plastic behavior and some lattice structures fracture. This simulation tool can be used in the future to predict and optimize the behavior of this lattice structure but only while operating elastically.

Flexural-gravity wave scattering due to a crack in a floating ice sheet in the perspective of wave blocking in a three-layer fluid

Flexural-gravity wave blocking is demonstrated in a three-layer fluid having a floating ice-covered surface in the water of finite depth. The study reveals that wave blocking occurs for higher values of compressive force in either of the modes, which depends on the density ratio and the wave frequency. Two (three) roots of the dispersion relation coalesce at the blocking (saddle) frequencies. Further, within the blocking frequencies, the dispersion relation possesses five propagating wave modes, of which three are affiliated with the layer where blocking occurs, whilst the other two modes are connected with the wave motion propagating in the respective layers. Dead water analogue is established due to the propagation of internal waves along the interface when the thickness of an individual layer is either thin or the density of two consecutive layers is close to each other. Subsequently, the role of blocking dynamics on the flexural-gravity wave scattering by a linear crack in an ice sheet floating in a three-layer fluid is studied. The canonical energy balance relation is generalized to account for multiple propagating wave modes. The velocity potentials are expanded in terms of a scattering matrix to account for the multiple incidents and scattered wave modes within the blocking frequencies. The study depicts the occurrence of removable/jump discontinuities in the scattering coefficients, both at the points where blocking/mode conversion takes place. Irregularities in the ice sheet's deflection and interface elevations are due to the superposition of multiple propagating wave modes within the blocking frequencies.

The Bearing Capacity of Compressed Corrosion-Damaged Reinforced Concrete Elements under Lateral Pulse Loading

This article addresses the relevant problem of the stress–strain behavior of compressed reinforced concrete columns under lateral pulse loading. A simplified engineering method of analyzing the limit value of lateral pulse loading P, depending on longitudinal force N acting on the column, is developed. The proposed method involves the construction of the P-N curve that has three portions. Portion 1 describes the plastic deformation of concrete and rebars of that part of the structure that is mostly in bending. Portion 2 describes the state of the column that can trigger the brittle failure of the concrete along the normal section, and Portion 3 describes the high compression of the column that predominantly triggers its shear failure. For Portions 1 and 2, analytical relationships are obtained using equilibrium equations. Corrosive damage is taken into account in the analytical model as a reduction in the strength and deformability characteristics of the material. A conventional local corrosion spot can be considered; it can be located both in and outside of the area of action of lateral pulse loading. The results obtained using the proposed model were compared with the results of numerical studies and a full-scale experiment. As a result of testing the developed engineering technique, it was found that it provides a safety margin for corrosion-damaged elements of 0.20–0.8 of the ultimate value of horizontal impulse at operational values of compressive force. The spot corrosion damage considered in the paper leads to a 10–60% strength reduction in compressed columns, depending on their location.

Developing a method of accounting for the existence of local surface heat exchange in rods of variable cross-section

The load-bearing elements of a number of strategic equipment are of limited length and variable cross-section. Most of them are exposed to certain types of heat sources. In order to ensure the reliable operation of this equipment, it is necessary to know the temperature field along the length of the variable cross-section rod. In this paper, a computational algorithm and a method for determining the temperature field along the length of a rod with a limited length and variable cross-section are proposed. They are based on the fundamental laws of conservation of energy. The nonlinearity of the process is due to nonlinear dependencies of the areas of the variable cross-section on the coordinate. The radius of the cross-section of the rod decreases linearly along the entire length, starting from the left end. The side surface of the first and third discrete elements of the rod is heat-insulated. Convective heat exchange with the environment takes place on the side surface of the second discrete element of the rod. The cross-sectional area of the left end of the rod is under the heat flow with a constant intensity, and a heat flow with different intensities is supplied to the right end, wherein the heat transfer coefficient is considered constant. For this task, you must first determine the law of temperature distribution along the length of the rod. In addition, if one end is rigidly fixed and the other end is free, the elongation must be calculated depending on the available heat sources, the physical and geometric characteristics of the rod, taking into account the presence of insulation. In case of pinching of both ends of the investigated rod, the value of axial compressive force is calculated taking into account the addition of real factors. The distribution of all components of the strain, stress, and displacement field is also defined

Forecasting supercritical behavior of drill strings in horizontal wells

The determining factor in the current changes in the world energy balance and its structure, as well as the global development of the oil and gas industry, is currently the technological factor. As a result, fundamentally new categories of horizontal and inclined wells appeared and developed. They give a multiple increase in flow rates, as they increase the production area many times over. They are used in the development of offshore projects, in swampy and very difficult areas, to increase oil recovery, restoration of inactive wells.
 New technologies based on the method of horizontal drilling have revolutionized the practice and theory of world oil production, as they have allowed the destruction of offshore oil and gas fields without the construction of expensive offshore foundations and platforms.
 When drilling horizontal wells, as a rule, the main cause of emergencies is the loss of stability of the drill string, its bifurcation protrusion and the maximum frictional interaction with the well wall. The issues of theoretical modeling of the phenomenon of unstable protrusion of columns are associated with significant difficulties, the main of which is due to the need to set the Sturm-Liouville boundary value problem on a large length of drill string. Because for deep wells, the drill string becomes geometrically similar to a human hair, many traditional mathematical methods used to integrate solving equations become poorly convergent in these cases.
 Based on the theory of curvilinear flexible rods, the problem of theoretical modeling of supercritical states of drill strings taking into account their contact interaction with the walls of oil and gas wells is set. Analytical solutions of the problem are constructed, which determine the critical values of external tensile or compressive longitudinal force and torque at a given difference in the diameters of the cavity and the drill string, the zones of supercritical states of drill strings are established.

Compressive forces influence on the vibrations of double beams

Abstract The influence of compressive forces on the lower and upper natural frequencies of the double beams has been studied in this article. Euler–Bernoulli’s hypotheses have been used to derive the natural frequency equations. Two asymmetric beams were assumed in this work, and four different boundary conditions were applied in these equations: Pinned–Pinned, Clamped–Clamped, Clamped–Free, and Clamped–Pinned. When the axial compressive force is increased about 18 times, it is observed that the lower natural frequencies decreased by 19% for PP beam, 8% for CC beam, 81% for CF beam, and 12% for CP beam. However, the greatest effect of the axial force on the higher frequencies is by reducing it in the CC beam by a ratio that does not exceed 2%. A rise in the values of axial compressive force causes a reduction in the lower natural frequencies, mostly for the CF beam, while it has a little effect on the higher natural frequencies. Similarly, when the compressive forces on the upper and lower beams fluctuate simultaneously, their effect is doubled on the frequencies when the axial compressive force on one of the two beams changes only.

Compressive Strength of Temporary Crowns Made from Default design in Two Types of Software.

Various default values in each software can eventually lead to different crown thicknesses and affect their compressive strength. This study aimed to compare the compressive strength of temporary crowns made with the milling machine, designed in Exocad and 3Shape Dental System software. In this in vitro study, 90 temporary crowns were made and evaluated based on each software settings. For this purpose, a sound premolar was first scanned as a pre-operative model by 3Shape laboratory scanner. The standard tooth preparation and scanning were performed, and then the temporary crown files (designed by each software) were transferred to the Imesicore 350i milling machine. A total of 90 temporary crowns (45 based on the file of each software) were made using poly methyl methacrylate (PMMA) vita cad-temp block. The value of compressive force displayed on the monitor was recorded at the first crack and the ultimate failure of the crown. The first crack and the ultimate strength of crowns designed with the Exocad software was 903.5±96N and 1490±139.3N and for crowns designed with 3Shape Dental System software was 1060.4±160.2N and 1691.1±73.9N, respectively. The amount of compressive strength of temporary crowns made with 3Shape Dental System was significantly higher than those made with Exocad software and this difference was statistically significant(p= 0.000). The compressive strength of temporary dental crowns made by both softwares is in a clinically acceptable range, but considering that the average compressive strength in the 3Shape Dental System group was slightly higher than of the other group, it is preferable to design and fabricate with 3Shape Dental System software to increase the compressive strength of these crowns.

Virtual modelling and analysis of manual material handling activities among warehouse workers in the construction industry.

Musculoskeletal risks (MSRs) are a major concern among construction warehouse workers due to the lifting, carrying and lowering of heavy loads. The objective of this study was to reduce MSRs among warehouse workers in the construction industry using virtual modelling and analysis of activities. A preliminary study was carried out using the Standard Nordic Questionnaire. Biomechanical analysis, Ovako Working posture Assessment System (OWAS) and Rapid Upper Limb Assessment (RULA) were used to analyse the material handling activities. Virtual modelling was used develop the manikins with autoclaved aerated concrete (AAC) blocks at different carriage modes and stacking heights for the analysis. The preliminary study results revealed a higher prevalence of risk at their lower back (73.24%) among the construction warehouse workers. Biomechanical analysis showed a higher risk at L4-L5 joint of lumbar spine during overhead and bending postures for stacking the blocks. Posture analysis results of OWAS indicated a lower risk in overhead carriage mode. Detailed analysis with RULA confirms this result. Mean compressive force values at stacking heights were showed a significant difference (p < 0.05) in 8, 13, 18 and 21 kg AAC blocks. However, stacking height with a range of 120-140 cm was found as safer to the workers by considering all block sizes. An ergonomic intervention based on safer stacking heights was developed to reduce MSRs to an acceptable range. It improves productivity of handling the AAC blocks by reducing the cycle time. The intervention can be adapted for handling of similar materials in the construction industry.

Triad resonance of flexural gravity waves in a two-layer fluid within the framework of blocking dynamics

The present study deals with the formation of triads in flexural gravity waves in a two-layer density stratified fluid having a flexible plate-covered surface and an interface within the framework of blocking, which can be used as a mechanism for understanding the spectral distribution of wave energy. The physical model is considered in a two-dimensional Cartesian coordinate system, and the formations of triads are discussed geometrically and validated analytically. The study demonstrates the formation of at most eight triads of three different classes for flexural gravity waves before the threshold of blocking, whereas a maximum of six triads of three different classes have been reported in the case of free-surface gravity waves. However, at least twenty triads are formed for any frequency within the blocking limits for the compressive force lying within the threshold of blocking and buckling limit, irrespective of water depth. On the other hand, 24 triads are formed for a certain frequency in the left neighborhood of the primary blocking point, while thirty triads occur when the frequency is considered in the right neighborhood of the secondary blocking point for specific values of compressive force and density ratio in the case of deep water/short flexural gravity waves in both the layers. In addition, a new class of triad, which is rarely found in the case of surface gravity waves, occurs for a certain frequency within the blocking limits for a suitable choice of compressive force and density ratio in the case of waves in deep/intermediate upper layer depth.

Gravity wave interaction with an articulated submerged plate resting on a Winkler foundation

Surface gravity wave interaction with an articulated flexible submerged plate in the presence of lateral compressive force is investigated within the framework of blocking dynamics, assuming that the submerged plate is resting on a uniform Winkler foundation. The problem is studied considering small-amplitude plate response and linearised water wave theory in finite water depth. The loci of the dispersion relation reveal the occurrence of wave blocking in the submerged plate mode for a range of wave frequency and compressive force when the submerged plate is resting on a Winker foundation. However, in the absence of the Winkler foundation, no wave blocking occurs in the plate mode irrespective of the values of compressive force, and plane wave propagation in plate mode does not happen for particular values of compressive force. Four propagating wavenumbers exist within the blocking frequencies, of which one is in the surface mode, and others are in the submerged plate mode. Thus, to account for the four propagating wave modes, the existing solution approach for a pair of propagating wave modes is modified in an appropriate manner within the limit of blocking frequencies. Consequently, the energy relation is obtained using Green’s identity, in which the reflection and transmission coefficients are a combination of the amplitudes of different reflected and transmitted wave modes and the associated energy transfer rates. The reflection coefficient in the submerged plate mode jumps from one to zero for very small values of frequency due to the introduction of the Winkler foundation in the presence of compressive force. In addition, zero wave reflection occurs for a higher frequency range with an increase in the values of the Winkler constant. Removable discontinuities are observed at the blocking and saddle points, whilst jump discontinuities occur in the reflection and transmission coefficients due to the change of incident wave mode within the blocking frequencies. Linear time-dependent displacements in surface and submerged plate modes are presented prior to the blocking limit.

Analysis of the loss of stability of open profile thin-walled rods, into account the imperfections of the form

It was made the analysis of influence the geometric imperfections to form on the stability of centrally compressed thin - walled rods of open profile with different wall thickness. The software complex of finite element analysis NASTRAN was used to create computer models of rods. Shelves and walls of rods are modeled as a set of quadrangular shell elements with six degrees of freedom in the node. Geometric imperfections are modeled in the form of the first general form of loss the stability of rods with an ideal surface, which are obtained from the linear calculation of stability which is rigidly fixed at the bottom and articulated at the top. With the help of a specially created program, the amplitude of imperfections in the shape of the rods was proportional to the wall thickness. Calculations of the stability of open-profile rods were performed in a linear formulation by the Lanzosch method, and in a nonlinear formulation by the Newton-Rafson method. Was received the values of the critical load and the corresponding forms of deformation of the rods with an ideal surface and taking into account the imperfections of the shape of different amplitude. The research results of stability of open-profile rods compared to experimental, obtained in 2016 in the laboratory of the Faculty of Civil Engineering, University in Zagreb (Croatia), and analytical and numerical calculations obtained using the ABAQUS software in 2020 at the Faculty of Civil Engineering, Brest State Technical University Faculty (Belarus). Comparative analysis showed that the critical values of compressive forces obtained in this work in the calculations of the stability of the rods in a nonlinear formulation using the computational procedures of the software package NASTRAN, was less than analytical and experimental. The critical forces obtained analytically are bigger than the numerical results of all researchers. The coincidence of numerical values of critical forces was detected in the case of an open profile rod with an ideal surface thickness of 0.0011 m and a mismatch in 0.003 m. The stability of rods research, taking into account the simulated imperfections of the form showed that the increase in the amplitude of imperfections had little effect on the critical values of compressive forces. This indicates that the model of geometric imperfections of the rods in the form of a general form of loss of stability is not the most dangerous for the stability of rods with such a profile, mounting and load. Therefore, there is need in further research of stability of the rods to perform modeling of geometric imperfections, for example, as the forms of their deformation in the ultimate state and from the action of operating load, which are obtained in nonlinear formulation.

Experimental investigation on reinforced concrete beams subjected to axial compressive and shear forces

AbstractThis paper presents two experimental campaigns carried out on 36 reinforced concrete (RC) beams (with and without shear reinforcement) subjected to a three‐point bending loading with a shear force on the one hand, an axial compressive load and a negative bending moment applied at each end of the beams on the other hand. Such a loading configuration makes it possible to investigate the influence of both axial compression and negative bending moment on the shear capacity of RC beams. For each campaign, three values of axial compressive force were studied, and the test beams were divided into two series with low and high negative bending moment. During the tests, Digital Image Correlation technique was used to capture the cracking evolution of the specimens. Besides, the experimental shear strengths of the beams are confronted to the predictions of Eurocode 2 in order to assess its practical validity. Finally, a semi‐analytical method proposed by Wahbi et al. 2021 (A failure criterion for RC beams subjected to axial and transverse loadings) for evaluating the resistance domain of RC elements subjected to transverse and axial loads, is extended in this paper to take into account the negative bending moment and compared to the experimental results.

Effect of psyllium husk addition on the instrumental texture and consumer acceptability of high-fiber wheat pan bread and buns

The consumption of recommended amount of dietary fiber is a challenge not only for most consumers but also for the food scientists to design fiber-enriched foods with acceptable eating quality, texture, color and flavor. The addition of psyllium husk (PS) significantly made the bread texture softer with increasing levels, producing the lowest compression force value (2.48 ± 0.37 N) at a 5% level. Addition of coarse wheat bran (at 10 and 20% levels) to white wheat flour (WWF) produced a significantly softer bread texture (4.65 ± 0.61 to 5.27 ± 0.32 N) compared with the harder texture with the fine wheat bran addition (5.04 ± 0.33 to 6.82 ± 0.57 N) for the control samples, respectively. When psyllium at 5% level was added to either the WWF or wholegrain wheat flour (WGF), it produced a significantly softer bread texture. Interestingly, the incorporation of diacetyl tartaric acid esters of mono- and diglyceride (DATEM) emulsifier (0.5%) in the WWF or WGF bread samples containing 5% psyllium did not significantly improve the textural properties of bread samples. When WWF + 5%PS (4.03 ± 0.12 N) buns were compared with WGF + 5%PS, the WGF +5%PS buns (7.37 ± 0.16 N) had a significantly harder texture. The results of compression force (N) and higher consumer acceptability values of these products clearly brought out the superior textural properties of wheat pan bread and buns made by this newer approach, than the common approach of using only the wholegrain wheat flour. Future studies on the effect of various wheat bran treatments, such as steaming or extrusion on the textural properties of pan bread and buns are recommended.

Designing of Steel CHS Columns Showing Maximum Compression Resistance

The paper deals with a shape optimisation procedure of steel, compressed bars. Circular hollow sections (CHS) of variable cross sections and variable wall thickness are taken into account. The proposed procedure for designing of steel rods exhibiting maximum compression resistance is effective and possible to use in engineering practice. The advantage of the proposed shape of the bar is that it allows to increase the value of its load carrying capacity, i.e. it ensures the transfer of a higher value of compressive force than similar, solid struts of the same mass and length. The extent of the increase in the load capacity relative to the load capacity of the reference solid, cylindrical bar depends on the slenderness of the reference bar and ranges from 60% to 170%. Due to this very beneficial fact, it can be used wherever it is required to maintain a certain stiffness and an increased value of compressive force is desired, as well as in constructions where it is necessary to reduce weight while maintaining the adopted mechanical parameters, e.g. values of load bearing capacity. Final results achieved in the research were presented in the form of the flow chart allowing to design the compressed columns of optimum shape.

Compression force variability in mammography in Ghana – A baseline study

IntroductionBreast compression during mammographic examinations improves image quality and patient management. Several studies have been conducted to assess compression force variability among practitioners in order to establish compression guidelines. However, no such study has been conducted in Ghana. This study aims to investigate the compression force variability in mammography in Ghana. MethodsThis retrospective study used data gathered from 1071 screening and diagnostic mammography patients from January, 2018–December, 2019. Data were gathered by seven radiographers at three centers. Compression force, breast thickness and practitioners' years of work experience were recorded. Compression force variability among practitioners and the correlation between compression force and breast thickness were investigated. ResultsMean compression force values recorded for craniocaudal (CC) (17.2 daN) and mediolateral oblique (MLO) (18.2 daN), were within the recommended values used by western countries. Most of the mammograms performed – 80% – were within the National Health Service Breast Screening Programme (NHSBSP) range. However, 65% were above the Norwegian Breast Cancer Screening Programme (NBCSP) range. Compression forces varied significantly (p = 0.0001) among practitioners. Compression forces increased significantly (p = 0.0001) with the years of work experience. A weak negative correlation (r = −0.144) and a weak positive correlation (r = 0.142) were established between compression force and breast thickness for CC and MLO projections respectively. ConclusionThis initial study confirmed that although wide variations in compression force exist among practitioners in Ghana, most practitioners used compression forces broadly within the range set by the NHSBSP. As no national guidelines for compression force currently exist in Ghana, provision of these may help to reduce the range of variations recorded. Implications for practiceConfirmation of variations in compression will guide future practice to minimize image quality disparities and improve quality of care.

Mathematical Model Describing the Influence of Geometrical Parameters of Multichannel Dies on the Limit Force of Dry Ice Extrusion Process.

The article presents a formulated mathematical model that enables the determination of the required compressive force in the extrusion process of dry ice employing multichannel dies. This is the main parameter in the piston-based dry ice extrusion process. The indicated model was developed for the purpose of further improvement of the energy efficiency of this extrusion process. It allows for the determination of the value of compressive force by accounting for 12 variables related to the geometrical parameters of the die and the physical characteristics of dry ice. Furthermore, the paper also provides descriptions of the empirical study methodologies together with the results. These were carried out in order to determine the difference between the results of mathematical modeling and actual measurement results. The final part of the article presents the results of the analysis of the mathematical model’s sensitivity to the change of the physical characteristics of dry ice. The formulated tool may be employed to adapt the geometric parameters of the die in order to obtain the desired compressive force value and dry ice granulation with reduced energy consumption.

Research Note: Texture characteristics of wooden breast fillets deboned at different postmortem times

The study aimed to understand whether deboning time contributes to the altered texture attributes of wooden breast (WB) fillets. To this purpose, 30 unaffected (NORM) and 30 severely affected (WB) carcasses were selected at 15 min postmortem (PM) and allotted into treatments with different deboning times: A (5 NORM + 5 WB; right fillets deboned at 15 min PM), B (5 NORM + 5 WB; right fillets deboned at 3 h PM), and C (5 NORM + 5 WB; right fillets deboned at 6 h PM). Left fillets from each carcass were deboned at 24 h PM. Multiple instrumental texture analyses were performed on the cranial-middle portion of the Pectoralis major muscles. Irrespective of deboning time, all fillets were subjected to a single 30% compression in the raw state at 24 h PM. All fillets were cooked at 24 h PM and subjected to shear force assessments at 48 h PM using blunt Meullenet-Owens razor shear, Meullenet-Owens razor shear, and Warner-Bratzler shear force. Using an ANOVA mixed model, deboning time was evaluated as a fixed effect within muscle condition (sampling session and carcass ID as random effects). Compression force assessment of raw meat at 24 h PM showed that WB fillets exhibited the greatest hardness when they were deboned at 6 h PM (15 min = 35.4 N; 3 h = 30.9 N; 6 h = 48.0 N; 24 h = 30.6 N; P < 0.05). Differently, deboning time had no effect (P > 0.05) on raw compression force values in NORM fillets. In cooked NORM fillets, shear force values were the greatest in fillets deboned at 15 min, and shear force gradually declined with deboning time through 24 h PM. On the contrary, no changes (P > 0.05) in shear values due to different deboning times were observed in cooked WB meat regardless of shear method. These results suggest that early PM changes in breast muscles and their influence on meat texture are different between normal and WB fillets.

MODELING THE TELESCOPIC CONNECTION DEVICE OF RAINBOW MUSCLE PROTESES

The aim: Mathematical modeling and peculiarities of the proposed telescopic connection design. Materials and methods: For the implementation of the mathematical model of telescopic joints of removable dentures, elements of the external and internal parts of such a design having the same nominal angles of cones, or identical nominal cones of these parts are considered. Results: Dependence of retention force is determined from various parameters, equating it with equilibrium values of compressive dynamic force and the total force of friction. Connection is set between the separate geometricalparameters of elements of telescopic cone connection andoperating between them various internal and external efforts.At creation of different individual modifications of theseconnections, gives possibility, attracting the values ofcorresponding geometrical or po wer elements, that isrationed or accepted on results measuring or scanouts, toexpect other parameters that is determined in dependenceon preliminary appointed. Conclusions: The given mathematical dependences can be represented as algorithms of calculation and realized by computer programs.