scholarly journals ОСОБЛИВОСТІ ЗАСТОСУВАННЯ МЕТОДІВ ФІЗИЧНОГО МОДЕЛЮВАННЯ ДЛЯ АНАЛІЗУ ПРОЦЕСУ ПРИЗЕМЛЕННЯ ПАРАШУТНИХ ПЛАТФОРМ НА НАДУВНІ ПОВІТРЯНІ АМОРТИЗАТОРИ

2021 ◽  
pp. 112-124
Author(s):  
А. В. Бетин ◽  
Д. А. Бетин ◽  
И. В. Калужинов
Keyword(s):  
Soft Tissue ◽  
Physical Modeling ◽  
Gas Dynamics ◽  
Physical Modelling ◽  
Object Modeling ◽  
Similar Model ◽  
Theoretical Substantiation ◽  
Modeling Methods ◽  
Shock Absorbers ◽  
The Impact

Research has been carried out aimed at developing the theoretical bases of physical modelling of landing processes of parachute platforms on inflatable air shock absorbers. At the same time, the features of the application of physical modeling methods for solving this task are considered. The conditions, landing features and operation of parachute platform devices at landing on inflatable air shock absorbers are determined. It is shown that presently parachute-depreciation systems have become widespread, in which soft tissue shells are used, filled through the inlet openings with atmospheric or air injected from gas bottles air. The operation of these devices is based on the compression of air in the shell and expiration of him through exit holes (valves). At the same time, air inflatable shells absorb the kinetic energy of the impact, controlling the release of air through exit holes.It has been established that the most effective method for studying the behavior of a dropped vehicle is physical modelling, which uses a free-flying dynamically similar model (FDSM) or stand dynamically similar model (DSM) of a dropped object as an research object. Modeling of landing processes of parachute platforms on inflatable air shock absorbers is not related to the dynamics of the flight and air flow around surfaces. Therefore, for this task, the existing developments in physical modelling of dynamics flight cannot be applied, and for the theoretical substantiation of the dynamic similarity to modeling motion, it makes sense to use the laws of gas dynamics in regard to air shock absorbers.

The impact of the digital economy on the development of Russian industry

2018 ◽  
Vol 34 (1) ◽  
pp. 3-9
Author(s):  
M. S. Abrashkin ◽  
A. A. Vershinin
Keyword(s):  
Automotive Industry ◽  
Industrial Production ◽  
Industrial Development ◽  
Digital Economy ◽  
Domestic Economy ◽  
Theoretical Substantiation ◽  
Russian Industry ◽  
Technological Structure ◽  
The Impact ◽  
Technological Paradigms

The article analyzes the market of computer technologies. The theoretical substantiation of the scientific category «digital economy» and its economic components was given. Identified patterns of development of the domestic economy on the basis of informatization, the change of technological paradigms and the dynamics of industrial production. Based on the materials of the automotive industry, the influence of the digital economy on the internal industrial and technological structure of the industry and the results of its activities was proved. Also, the paper presents the main problems of sustainable industrial development in the context of socio-technical and economic means of developing science and technology in Russia.

Modeling the impact of soft tissue on axial transmission measurements of ultrasonic guided waves in human radius

2008 ◽  
Vol 124 (4) ◽  
pp. 2364-2373 ◽  
Author(s):  
Petro Moilanen ◽  
Maryline Talmant ◽  
Vantte Kilappa ◽  
Patrick Nicholson ◽  
Sulin Cheng ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Guided Waves ◽  
Ultrasonic Guided Waves ◽  
Transmission Measurements ◽  
The Impact ◽  
Axial Transmission

scholarly journals Retrospective analysis of the impact of symptom duration on prognosis in soft tissue sarcoma

2007 ◽  
Vol 32 (3) ◽  
pp. 381-384 ◽  
Author(s):  
A. Saithna ◽  
P. B. Pynsent ◽  
R. J. Grimer
Keyword(s):  
Soft Tissue ◽  
Soft Tissue Sarcoma ◽  
Retrospective Analysis ◽  
Symptom Duration ◽  
The Impact

COL1A1 GENE POLYMORPHISM IN MATERNITY PATIENTS WITH SOFT TISSUE INJURIES

2021 ◽  
pp. 54-58
Author(s):  
Kh.M. Laypanova ◽  
N.A. Zharkin ◽  
Yu.A. Shatilova
Keyword(s):  
Soft Tissue ◽  
Gene Polymorphism ◽  
Gene Mutation ◽  
Pelvic Floor Muscle ◽  
Soft Tissue Injuries ◽  
Birth Trauma ◽  
Homozygous Mutation ◽  
Col1a1 Gene ◽  
Tissue Injuries ◽  
The Impact

The aim of the paper is to determine the impact of COL1A1 gene polymorphism on soft tissue injuries in maternity patients. Materials and Methods. The study involved 62 maternity patients who were divided into 2 groups. The first group included 45 patients (72.5 %) without type 1 collagen mutation, alpha 1 Sp1-polymorphism (G2046T) G/G. The second group consisted of 16 patients (27.5 %) with mutation in COL1A1 gene, Sp1-polymorphism (G2046T) G/T. During the study, a homozygous mutation, Sp1-polymorphism (G2046T) T/T was observed in one patient. Age, parity and mean fetal weight of women were comparable. Results. In patients with the COL1A1 mutation, Sp1-polymorphism (G2046T), the incidence of soft tissue birth injuries was 2.3 times higher than in those without such a mutation. Thus, it was confirmed that COL1A1 gene mutation contributes to the soft tissue trauma of the birth canal. It can be regarded as a prognostic criterion and as a basis for preventive measures during pregnancy. Conclusion. Birth trauma risks remain a controversial issue. One of the factors may be COL1A1 gene mutation. Key words: birth trauma, pelvic floor muscle insufficiency, collagen 1 gene polymorphism (COL1A1). Цель работы – определить роль полиморфизма гена COL1A1 у женщин с родовыми травмами мягких тканей родовых путей. Материалы и методы. В исследовании приняло участие 62 родильницы, которые были разделены на 2 группы. В первую группу включены 45 (72,5 %) родильниц, у которых мутация коллагена типа 1, альфа 1 Sp1-polymorphism (G2046T) G/G не обнаружена. Во второй группе, состоящей из 16 (27,5 %) родильниц, обнаружена мутация гена COL1A1 Sp1-polymorphism (G2046T) G/T. В процессе проведения исследования у одной пациентки обнаружена гомозиготная мутация Sp1-polymorphism (G2046T) T/T. Пациентки были сопоставимы по возрасту, паритету и средней массе плода. Результаты. У пациенток с мутацией COL1A1 Sp1-polymorphism (G2046T) частота родовых травм мягких тканей оказалась в 2,3 раза выше, чем у пациенток без мутации. Таким образом, подтверждено, что мутация данного гена имеет определенное значение в реализации риска травм мягких тканей родовых путей, что может послужить прогностическим критерием и основанием для проведения профилактических мероприятий в период беременности. Выводы. Вопрос о рисках родового травматизма остается спорным. Одним их факторов может явиться мутация гена COL1A1. Ключевые слова: родовой травматизм, недостаточность мышц тазового дна, полиморфизм гена коллагена 1 (COL1A1).

The Ligamentary System and the Segmental Musculature of Nephtys

1960 ◽  
Vol s3-101 (54) ◽  
pp. 149-176
Author(s):  
R. B. CLARK ◽  
M. E. CLARK
Keyword(s):  
Body Wall ◽  
The Body ◽  
Power Stroke ◽  
Coelomic Fluid ◽  
Unusual Structure ◽  
Shock Absorbers ◽  
Proximal Half ◽  
Unique System ◽  
Body Wall Muscles ◽  
The Impact

Nephtys lacks circular body-wall muscles. The chief antagonists of the longitudinal muscles are the dorso-ventral muscles of the intersegmental body-wall. The worm is restrained from widening when either set of muscles contracts by the combined influence of the ligaments, some of the extrinsic parapodial muscles, and possibly, to a limited extent, by the septal muscles. Although the septa are incomplete, they can and do form a barrier to the transmission of coelomic fluid from one segment to the next under certain conditions, particularly during eversion of the proboscis. Swimming is by undulatory movements of the body but the distal part of the parapodia execute a power-stroke produced chiefly by the contraction of the acicular muscles. It is suspected that the extrinsic parapodial muscles, all of which are inserted in the proximal half of the parapodium, serve to anchor the parapodial wall at the insertion of the acicular muscles and help to provide a rigid point of insertion for them. Burrowing is a cyclical process involving the violent eversion of the proboscis which makes a cavity in the sand. The worm is prevented from slipping backwards by the grip the widest segments have on the sides of the burrow. The proboscis is retracted and the worm crawls forward into the cavity it has made. The cycle is then repeated. Nephtys possesses a unique system of elastic ligaments of unusual structure. The anatomy of the system is described. The function of the ligaments appears to be to restrain the body-wall and parapodia from unnecessary and disadvantageous dilatations during changes of body-shape, and to serve as shock-absorbers against the high, transient, fluid pressures in the coelom, which are thought to accompany the impact of the proboscis against the sand when the worm is burrowing. From what is known of its habits, Nephtys is likely to undertake more burrowing than most other polychaetes.

Management of trauma to the anterior segment of the maxilla: alveolar fracture and primary incisors crown and root fracture

2021 ◽  
Vol 33 (2) ◽  
pp. 16-20
Author(s):  
Muna S Khalaf ◽  
Bayan S Khalaf ◽  
Shorouq M Abass
Keyword(s):  
Soft Tissue ◽  
Primary Teeth ◽  
Alveolar Bone ◽  
Anterior Segment ◽  
Dental Trauma ◽  
Permanent Tooth ◽  
Permanent Teeth ◽  
Normal Position ◽  
Anterior Teeth ◽  
The Impact

Background: An injury to both the primary and permanent teeth and the supporting structures is one of the most common dental problems seen in children. Splinting is usually difficult or impossible to perform in the primary dentition (due to diminutive room size and lack of patient cooperation). Healing must, therefore, occur despite mobility at the fracture line, usually resulting in interposition of connective tissue. In some instances, infection will occur in the coronal pulp. The present study reported a case of trauma to the anterior primary teeth and alveolar bone in a four year old child. The trauma has caused fracture to the crowns and roots of the primary anterior teeth. The following case was managed in a procedure that may provide primary teeth subjected to trauma a better chance than extraction with a better prognosis. Case presentation: a 4 and a half year old child was subjected to trauma in anterior segment of maxilla. Suturing of the torn soft tissue was the first step followed by pulpotomy for the left primary lateral incisor. Fixation of the right primary central and lateral incisors was done by acid etch wire fixation. Both clinical and radiographic follow up was carried out for 6.4 years. Results: healing of the soft tissue was observed after one week and completed after two months. Fixation of the teeth continued for ten months. The fracture lines in the roots remained in position. Clinically there was no sign of any pulpal inflammation or necrosis. Radiographically, no signs of infection to the surrounding tissues could be seen, no resorption in the alveolar bone, external or internal resorption of the root did not happen also. After ten months fixation ended and the wire was removed. At that time there was normal resorption of the roots of the primary incisors in relation with the normal development of the permanent incisors. After 3 years both permanent central incisors erupted in their normal position. After 6.4 years all four permanent incisors erupted into occlusion in their normal position. Conclusion: primary teeth with root fractures and severely mobile coronal fragments can be treated by a conservative approach. The severity of the sequels is directly related to the degree of permanent tooth formation (child’s age), type of dental trauma and extent of the impact. Key words: trauma, primary incisors, fractured crown and root

Quantifying Variability in Lumbar L4-L5 Soft Tissue Properties for Use in Finite-Element Analysis

2016 ◽  
Vol 1 (3) ◽  
Author(s):  
Dana J. Coombs ◽  
Paul J. Rullkoetter ◽  
Peter J. Laz
Keyword(s):  
Finite Element ◽  
Soft Tissue ◽  
Experimental Testing ◽  
Intersubject Variability ◽  
Probabilistic Representation ◽  
Posterior Portion ◽  
Annulus Fibrosis ◽  
Interspinous Ligament ◽  
Constitutive Material Model ◽  
The Impact

Soft tissue structures of the L4-L5 level of the human lumbar spine are represented in finite-element (FE) models, which are used to evaluate spine biomechanics and implant performance. These models typically use average properties; however, experimental testing reports variation up to 40% in ligament stiffness and even greater variability for annulus fibrosis (AF) properties. Probabilistic approaches enable consideration of the impact of intersubject variability on model outputs. However, there are challenges in directly applying the variability in measured load–displacement response of structures to a finite-element model. Accordingly, the objectives of this study were to perform a comprehensive review of the properties of the L4-L5 structures and to develop a probabilistic representation to characterize variability in the stiffness of spinal ligaments and parameters of a Holzapfel–Gasser–Ogden constitutive material model of the disk. The probabilistic representation was determined based on direct mechanical test data as found in the literature. Monte Carlo simulations were used to determine the uncertainty of the Holzapfel–Gasser–Ogden constitutive model. A single stiffness parameter was defined to characterize each ligament, with the anterior longitudinal ligament (ALL) being the stiffest, while the posterior longitudinal ligament and interspinous ligament (ISL) had the greatest variation. The posterior portion of the annulus fibrosis had the greatest stiffness and greatest variation up to 300% in circumferential loading. The resulting probabilistic representation can be utilized to include intersubject variability in biomechanics evaluations.

scholarly journals Do Prophylactic Knee Braces Protect the Knee Against Impacts or Tibial Moments? An In Vitro Multisensory Study

2018 ◽  
Vol 6 (11) ◽  
pp. 232596711880539 ◽  
Author(s):  
Steffen Paul Hacker ◽  
Florian Schall ◽  
Frank Niemeyer ◽  
Nicolas Wolf ◽  
Anita Ignatius ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Cruciate Ligament ◽  
Joint Line ◽  
Strain Change ◽  
Posterior Direction ◽  
Knee Braces ◽  
Anterior Cruciate ◽  
The Impact ◽  
Joint Acceleration

Background: Knee braces are prescribed by physicians to protect the knee from various loading conditions during sports or after surgery, even though the effect of bracing for various loading scenarios remains unclear. Purpose: To extensively investigate whether bracing protects the knee against impacts from the lateral, medial, anterior, or posterior directions at different heights as well as against tibial moments. Study Design: Controlled laboratory study. Methods: Eight limb specimens were exposed to (1) subcritical impacts from the medial, lateral, anterior, and posterior directions at 3 heights (center of the joint line and 100 mm inferior and superior) and (2) internal/external torques. Using a prophylactic brace, both scenarios were conducted under braced and unbraced conditions with moderate muscle loads and intact soft tissue. The change in anterior cruciate ligament (ACL) strain, joint acceleration in the tibial and femoral bones (for impacts only), and joint kinematics were recorded and analyzed. Results: Bracing reduced joint acceleration for medial and lateral center impacts. The ACL strain change was decreased for medial superior impacts and increased for anterior inferior impacts. Impacts from the posterior direction had substantially less effect on the ACL strain change and joint acceleration than anterior impacts. Bracing had no effect on the ACL strain change or kinematics under internal or external moments. Conclusion: Our results indicate that the effect of bracing during impacts depends on the direction and height of the impact and is partly positive, negative, or neutral and that soft tissue absorbs impact energy. An effect during internal or external torque was not detected. Clinical Relevance: Bracing in contact sports with many lateral or medial impacts might be beneficial, whereas athletes who play sports with rotational moments on the knee or anterior impacts may be safer without a brace.

The Effect of Explosion in a Tunnel Tube on its Damage

2018 ◽  
Vol 774 ◽  
pp. 265-270
Author(s):  
Petr P. Prochazka ◽  
Martin J. Válek
Keyword(s):  
Gas Dynamics ◽  
Solid Phase ◽  
Fiber Reinforced Concrete ◽  
Reinforced Concrete Structure ◽  
Air Velocity ◽  
Shell Elements ◽  
Final Volume ◽  
Flat Shell ◽  
The Impact ◽  
Geometric Compatibility

The aim of the work is to study the impact of an explosion in a tube on its damage. The theory of Landau-Liftschitz gas dynamics and the damage criterion by the Hoek-Brown in the structure are applied. If the charge is placed centrically in the tube, it is fairly easy to predict both the locations and damage levels. Therefore, the paper is oriented to the case where the charge is placed eccentrically. Air movement is described by the solution of non-linear Euler’s equations by final volume element method, while the response of the fiber reinforced concrete structure of the tube to impact waves is described by the time dependent 20-nodes flat shell elements. In order to ensure the geometric compatibility along the interface between the two media (structure, air), gas dynamics in the air is described by block elements, while the shell is approximated by the finite element. In this way, the problem solved is divided into a description of the air velocity and pressure and the velocity and stress in the solid phase, separately; interaction of the effects caused by the explosion initiated inside of the tube and its impact on the solid phase is concentrated along the interface between these two media. The calculation focuses on the early stages of interaction development when most likely damage is assumed.

scholarly journals ENHANCED MASS LOSS RATES IN RED SUPERGIANTS AND THEIR IMPACT ON THE CIRCUMSTELLAR MEDIUM

2019 ◽  
Vol 55 (2) ◽  
pp. 161-175
Author(s):  
L. Hernández-Cervantes ◽  
B. Pérez-Rendón ◽  
A. Santillán ◽  
G. García-Segura ◽  
C. Rodríguez-Ibarra
Keyword(s):  
Mass Loss ◽  
Stellar Evolution ◽  
Gas Dynamics ◽  
Numerical Experiments ◽  
Evolutionary Models ◽  
Solar Composition ◽  
Red Supergiants ◽  
The Impact ◽  
Circumstellar Medium ◽  
Loss Rates

In this work, we present models of massive stars between 15 and 23 M⊙ , with enhanced mass loss rates during the red supergiant phase. Our aim is to explore the impact of extreme red supergiant mass-loss on stellar evolution and on their circumstellar medium. We computed a set of numerical experiments, on the evolution of single stars with initial masses of 15, 18, 20 and, 23 M⊙ , and solar composition (Z = 0.014), using the numerical stellar code BEC. From these evolutionary models, we obtained time-dependent stellar wind parameters, that were used explicitly as inner boundary conditions in the hydrodynamical code ZEUS-3D, which simulates the gas dynamics in the circumstellar medium (CSM), thus coupling the stellar evolution to the dynamics of the CSM. We found that stars with extreme mass loss in the RSG phase behave as a larger mass stars.

Sign in / Sign up

Export Citation Format

Share Document