Technical design and stability analysis procedure for horizontal stability construction of roads and railways

Unstable sections of predominantly vertical roads and railways are usually stabilized by viaducts, while predominantly horizontal unstable sections of the same structures are regularly stabilized by special structures which have a common feature of spaciousness or massiveness, and which proportionally also require peculiarity in all aspects of the construction. The goal of the new solution is to avoid the highlighted structural peculiarity, that is, to apply a solution that will be more of a constructive element of roads and railways, like a viaduct in an approximate sense. There is such a solution, and that is the low-rise stable structure, which in a naturally appropriate way counteracts horizontal instabilities on low-rise objects. The horizontal effect on the object is converted to a vertical direction via this construction by means of pile coupling, while this effect is greatly reduced due to the effect of static interaction between the components of the coupling. If, instead of various vertical structures with horizontal anchors or mass structure retaining walls, we apply the slope-pile coupling at an optimal angle in the range of 15 to 20 degrees, then, by activating the external horizontal effect, i.e. instability, the primary axial resistance in the oblique pile is simultaneously activated through circumferential friction. The vertical component of this resistance decreases the active horizontal component, while the horizontal does the same, provided that the pile has a transverse static EI feature. This approach has not been used thus far in engineering practice and therefore represents a novelty. Therefore, it can be argued that by constructing a low-rise stable structure, we can achieve at least approximately the same structural impression that we enjoy regarding the viaduct construction for predominantly vertical instabilities.

ANALYSIS ON INCLINATION MONITORING OF ONLINE AGRICULTURAL MACHINERY EQUIPMENT BASED ON WSN (WIRELESS SENSOR NETWORK)

The shell of inclined conveyor of combine often has the defect of serious vibration. In order to solve this problem, this study uses the dynamic signal test and analysis system and control the electromagnetic directional valve to realize the horizontal stability control of agricultural machinery. In order to improve the bearing accuracy, this paper designs a bearing tilt detection device. When the tilt reaches its set point, an alarm can be issued to initiate an emergency response. Taking tractor as the object, the application of real-time tilt angle measurement algorithm on three-axis multifunctional turntable is tested. At the same time, the automatic leveling system of agricultural machinery was tested in the field, and the minimum inclination angle of the chute conveying all kinds of grain and oil materials was obtained. The image collected by AGV has the characteristics of high speed, high efficiency and small resolution error. It can also correct the tilt image in real time. This study is helpful to adapt to the new requirements of modern agricultural large-scale agricultural machinery or production facilities. The monitoring system has practical guiding significance in the construction process, and has a certain promotion value.

Anatomical versus non-anatomical configuration of double coraco-clavicular tunnel technique in acromioclavicular joint reconstruction

Purpose Horizontal instability is a common problem after acromioclavicular joint injuries. The aim of this study was to evaluate if there is a difference regarding horizontal stability between an anatomical and a non-anatomical configuration of the double tunnel coraco-clavicular ligament reconstruction of the acromioclavicular joint. Methods Thirteen acromioclavicular joints of human cadaveric shoulders in ethanol-glycerin fixation were included in the study and underwent cyclic anterior and posterior translational testing at a load of 70 N using an electromechanical uniaxial testing machine. The shoulders were randomly assigned to the following groups: double coraco-clavicular tunnel technique in an anatomical configuration (DCTa) and double coraco-clavicular tunnel technique in an inverse configuration of the anatomical position (DCTb). The dislocation was recorded with a 3D optical measuring system. Results The total horizontal displacement (p10 = 0.0221; p5000 = 0.082) was significantly higher for the non-anatomical reconstruction (DCTb) compared to the anatomical reconstruction (DCTa) after every measured amount of cycles. The increase in displacement for DCTb group was overall higher than the increase in displacement for DCTa group but without significance. Conclusion Reconstruction of the CC ligaments in an anatomical configuration with two suture devices results in a significantly higher stability of the AC joint in the horizontal plane than reconstruction of the CC ligaments in a non-anatomical configuration. Based on the results of this biomechanical in vitro study, the use of a double coraco-clavicular reconstruction should focus on an anatomically correct position of the suture devices.

Quantitative and Qualitative Surgical Anatomy of the Acromioclavicular Joint Capsule and Ligament: A Cadaveric Study

Background: The acromioclavicular (AC) capsule and ligament have been found to play a major role in maintaining horizontal stability. To reconstruct the AC capsule and ligament, precise knowledge of their anatomy is essential. Purpose/Hypothesis: The purposes of this study were (1) to determine the angle of the posterosuperior ligament in regard to the axis of the clavicle, (2) to determine the width of the attachment (footprint) of the AC capsule and ligament on the acromion and clavicle, (3) to determine the distance to the AC capsule from the cartilage border of the acromion and clavicle, and (4) to develop a clockface model of the insertion of the posterosuperior ligament on the acromion and clavicle. It was hypothesized that consistent angles, attachment areas, distances, and insertion sites would be identified. Study Design: Descriptive laboratory study. Methods: A total of 12 fresh-frozen shoulders were used (mean age, 55 years [range, 41-64 years]). All soft tissue was removed, leaving only the AC capsule and ligament intact. After a qualitative inspection, a quantitative assessment was performed. The AC joint was fixed in an anatomic position, and the attachment angle of the posterosuperior ligament was measured using a digital protractor. The capsule and ligament were removed, and a coordinate measuring device was utilized to assess the width of the AC capsule footprint and the distance from the footprint to the cartilage border of the acromion and clavicle. The AC joint was then disarticulated, and the previously marked posterosuperior ligament insertion was transferred into a clockface model. The mean values across the 12 specimens were demonstrated with 95% CIs. Results: The mean attachment angle of the posterosuperior ligament was 51.4° (95% CI, 45.2°-57.6°) in relation to the long axis of the entire clavicle and 41.5° (95% CI, 33.8°-49.1°) in relation to the long axis of the distal third of the clavicle. The mean clavicular footprint width of the AC capsule was 6.4 mm (95% CI, 5.8-6.9 mm) at the superior clavicle and 4.4 mm (95% CI, 3.9-4.8 mm) at the inferior clavicle. The mean acromial footprint width of the AC capsule was 4.6 mm (95% CI, 4.2-4.9 mm) at the superior side and 4.0 mm (95% CI, 3.6-4.4 mm) at the inferior side. The mean distance from the lateral clavicular attachment of the AC capsule to the clavicular cartilage border was 4.3 mm (95% CI, 4.0-4.6 mm), and the mean distance from the medial acromial attachment of the AC capsule to the acromial cartilage border was 3.1 mm (95% CI, 2.9-3.4 mm). On the clockface model of the right shoulder, the clavicular attachment of the posterosuperior ligament ranged from the 9:05 (range, 8:00-9:30) to 11:20 (range, 10:00-12:30) position, and the acromial attachment ranged from the 12:20 (range, 11:00-1:30) to 2:10 (range, 13:30-14:40) position. Conclusion: The finding that the posterosuperior ligament did not course perpendicular to the AC joint but rather was oriented obliquely to the long axis of the clavicle, in combination with the newly developed clockface model, may help surgeons to optimally reconstruct this ligament. Clinical Relevance: Our results of a narrow inferior footprint and a short distance from the inferior AC capsule to cartilage suggest that proposed reconstruction of the AC joint capsule should focus primarily on its superior portion.

BiPOD arthroscopically assisted bidirectional stabilisation technique for high-grade acromioclavicular joint injury: two-year clinical and radiological outcomes

Purpose The purpose of this study was to evaluate the intermediate-term clinical and radiological outcomes for acute, unstable acromioclavicular joint (ACJ) injuries treated with the arthroscopically assisted BiPOD stabilisation technique. Methods Twenty-three patients who sustained acute, unstable ACJ injuries were included in this prospective study. We recorded demographics, injury classification, time to surgery, clinical scores, radiological outcomes and complications; each patient completed a minimum of 2 years post-operative observation. Results Mean follow-up was 26 months (range, 24—34). Clinical outcomes scores demonstrated good 2-year results: relative Constant score, 97.9/100; ACJ Index, 89.4/100; Subjective Shoulder Value, 92.4/100 and Taft = 11.1/12. Final C–C distance showed a mean of 0.7 mm (SD ± 1.8 mm) at 2 years. Complication rate was 9%. Conclusion The BiPOD technique shows excellent, reliable intermediate-term results with a favourable complication rate compared to existing techniques; it provides a comprehensive surgical option for the stabilisation of acute ACJ injuries restoring both vertical and horizontal stability.

The Role of the Acromioclavicular Ligament in Acromioclavicular Joint Stability: A Cadaveric Biomechanical Study

Background: Acromioclavicular (AC) joint dislocation is evaluated using the radiologically based Rockwood classification. The relationship between ligamentous injury and radiological assessment is still controversial. Purpose/Hypothesis: To investigate how the AC ligament and trapezoid ligament biomechanically contribute to the stability of the AC joint using cadaveric specimens. The hypothesis was that isolated sectioning of the AC ligament would result in increased instability in the superior direction and that displacement >50% of the AC joint would occur. Study Design: Controlled laboratory study. Methods: Six shoulders from 6 fresh-frozen cadavers were used in this study. Both the scapula and sternum were solidly fixed on a customized wooden jig with an external fixator. We simulated distal clavicular dislocation with sequential sectioning of the AC and coracoclavicular (CC) ligaments. Sectioning stages were defined as follows: stage 0, the AC ligament, CC ligament, and AC joint capsule were left intact; stage 1, the anteroinferior bundle of the AC ligament, joint capsule, and disk were sectioned; stage 2, the superoposterior bundle of the AC ligament was sectioned; and stage 3, the trapezoid ligament was sectioned. The distal clavicle was loaded with 70 N in the superior and posterior directions, and the magnitudes of displacement were measured. Results: The amounts of superior displacement averaged 3.7 mm (stage 0), 3.8 mm (stage 1), 8.3 mm (stage 2), and 9.5 mm (stage 3). Superior displacement >50% of the AC joint was observed in stage 2 (4/6; 67%) and stage 3 (6/6; 100%). The magnitudes of posterior displacement were 3.7 mm (stage 0), 3.7 mm (stage 1), 5.6 mm (stage 2), and 9.8 mm (stage 3). Posterior displacement >50% of the AC joint was observed in stage 3 (1/6; 17%). Conclusion: We found that the AC ligaments contribute significantly to AC joint stability, and superior displacement >50% of the AC joint can occur with AC ligament tears alone. Clinical Relevance: The AC ligament plays an important role not only in horizontal stability but also in vertical stability of the AC joint.

Study of the contribution of horizontal stability in the probability model of the “hostpathogen” interaction system on the basis of millet varieties susceptible to smut

Digital control of breeding process, creation of mathematical models of living objects and management of plant life cycle is an urgent problem of modern times. Сreation of technologies that ensure implementation of the concept of advanced digital "smart" agriculture is impossible without basic mathematical models of "mass interactions" of natural living objects. This primarily affects the spread of certain diseases in populations. In the plant world, such a convenient model object is the well-studied "host-pathogen" system by the example of the interaction of millet and its smut disease. At present, the knowledge of the patterns of development of this disease in the millet plant is of a qualitative nature (virulence), and the quantitative characteristics (aggressiveness) are approximate. Only mathematical modeling of this process can accurately describe the development of the disease. This paper examines a probabilistic model and certain aspects of mathematical modeling using the example of identifying the laws of horizontal resistance to smut in susceptible millet genotypes.

Palatal Fracture Fixation on Severe Panfacial Fracture: Is There Any Clinical Significance?

Background: Fractures of the hard palate are infrequent. They are found in less then 10% of patients with midfacial fractures. They practically never occur in isolation and are usually part of alveolar process fractures or more complex midfacial fractures of the Le Fort type. Treatment of palatal fractures is planned and performed with the goal of restoring the transverse width of the palate, the anteroposterior projection of the maxillary arch, and the patient’s pretraumatic occlusal plane, as well as maintaining horizontal stability of the midface.Case Presentation: Reporting patient female 17 years old with panfacial fracture due to traffic accident. There was slight epidural haemorrhage on frontal area. The fractures are on upper face, midface, and lower face including the hard palate. We performed open reduction internal fixation on palate to correct the arch of the upper jaw. The other fracture site can be corrected easier. The approaches that we done are bicoronal, subsilier, and intraoral. The patient was successfully treated using bottom-up and outside-in sequence by accessing all facial injuries. Postoperatively, radiograph examination revealed good reduction and fixation of titanium plates, and physical examination revealed good functional and aesthetic outcomes.Conclusion: Palate fractures are relatively uncommon and are associated with significant rates of malocclusion and wound complications. These injuries are typically managed with plate fixation of the alveolar ridge with variable approaches to the palatal vault

Two-Dimensional Numerical Model for Stability Analysis of Tunnel Face Based on Particle Flow Code

In this paper, numerical simulations of face stability of shallow tunnels are carried out by using the particle discrete element codes PFC2D from the microscopic view. Progressive instability of the tunnel face is achieved through the withdrawal of the baffle used to simulate the tunnel face. Under different retreating displacement of the tunnel face, the evolution laws of support pressure on the tunnel face, the ground deformation, ground surface settlement and contact force chain in front of the tunnel face are studied. The results show that with the withdrawal of the tunnel face, the support pressure on the tunnel face can be divided into four stages, namely, the rapid decline stage, the minimum stage, the slow rising stage, and the horizontal stability stage. Moreover, based on the simulation results of the particle contact force chain, discriminated methods of failure zones are proposed. The research results obtained from this paper will provide theoretical support for the reasonable value of support pressure of a tunnel face in practical engineering.