Local Strengthening Research Articles

СПОРТ ЯК ПОЛЕ РЕАЛІЗАЦІЇ СОЦІАЛЬНО-ПОЛІТИЧНИХ ЗАПИТІВ МІЖНАРОДНОЇ СПІЛЬНОТИ

The importance of sport and sports entities as active factors of the international agenda formation is proven in this article. The arguments for replacing the classic actors of the world arena with non-standard units, such as individual athletes and sports teams and organizations are given in this context. While emphasizing the fact that they are becoming mouthpieces and lobbyists for specific demands of society more and more often, the analysis of such a phenomenon of politicization and socialization of actors as well as the actors’ tools in such activities as symbols, narratives and physical space is carried out as well. The main research topics of most scholars who focus on the mentioned relationship between politics and sports are nationalism, propaganda, the struggle of ideologies and power through the prism of politics in sport whereas this article also highlights the use of sport as a tool of communication and local identity strengthening. Some of the analyzed sources concern the fixation of events and personalities (Guillem Balague, Dave Zirin, Franklin Foer), while others tackle with philosophical and anthropological issues (Zygmunt Bauman, Erin Tarver, Christopher Gaffney), thanks to which a sufficient level of this phenomena is supplied (especially these are American and British researchers) as well as the need for a multidisciplinary approach to the choice of methodology and areas of analysis is outspoken. The aim of the article is not only to study the sources that shed the light on this issue, but also to give the international (Olympic Games, Mohammed Ali, Marcus Rashford, etc.) and Ukrainian examples (FC «Karpaty») from history and the present. The importance of analyzing fans’ narratives (banners, songs, perception of themselves and others, etc.) and symbolic objects of the urban landscape (stadiums and sports infrastructure in general) is emphasized in order to understand the trends in society that fans and objects represent.

Sustained Release of VEGF to Promote Angiogenesis and Osteointegration of Three-Dimensional Printed Biomimetic Titanium Alloy Implants.

Tumor resection and treatment of trauma-related regional large bone defects have major challenges in the field of orthopedics. Scaffolds that treat bone defects are the focus of bone tissue engineering. 3D printing porous titanium alloy scaffolds, prepared via electron beam melting technology, possess customized structure and strength. The addition of a growth factor coating to the scaffold introduces a specific form of biological activation. Vascular endothelial growth factor (VEGF) is key to angiogenesis and osteogenesis in vivo. We designed a porous titanium alloy scaffold/thermosensitive collagen hydrogel system, equipped with VEGF, to promote local osseointegration and angiogenesis. We also verified the VEGF release via thermosensitive collagen and proliferation and induction of the human umbilical vein endothelial cells (HUVECs) via the composite system in vitro. In vivo, using microscopic computed tomography (Micro-CT), histology, and immunohistochemistry analysis, we confirmed that the composite scaffold aids in angiogenesis-mediated bone regeneration, and promotes significantly more bone integration. We also discovered that the composite scaffold has excellent biocompatibility, provides bioactive VEGF for angiogenesis and osteointegration, and provides an important theoretical basis for the restoration of local blood supply and strengthening of bone integration.

THE IMPACT OF ICT IN ADULT AND NON FORMAL EDUCATION IN NIGERIA: A REVIEW

This article is attempting to comprehend the effects of Information and Communication Technology in the exercises of Adult and Non-Formal and Education. It diagrams various techniques to confer training by using Information and Communication Technology (ICT) apparatuses, developments, and arising patterns. Simultaneously, this text features the benefits accumulated by the utilization of Information and Communication Technologies (ICTs) in teaching and learning processes. The effect of Information and Communication Technology on all schooling areas raises difficulties for legislatures, educators and learners. There is a more noteworthy interest for and reception of innovation in training in adult and non-formal education. The realization of the potential of ICTs to improve educational practices is a series of pedagogical and practical challenges. This article considers the issues starting with the basic motivation behind instruction and closes by raising a progression of difficulties that instructive foundations should confront in case they are to effectively coordinate ICT into educating and learning rehearses. The inescapable utilization of ICTs for long-lasting learning just as local area strengthening is a huge pattern in realizing in the current century.

Utilizing local phase transformation strengthening for nickel-base superalloys

Almost 75 years of research has been devoted to producing superalloys capable of higher operating temperatures in jet turbine engines, and there is an ongoing need to increase operating temperature further. Here, a new disk Nickel-base superalloy is designed to take advantage of strengthening atomic-scale dynamic complexions. This local phase transformation strengthening provides the alloy with a three times improvement in creep strength over similar disk superalloys and comparable strength to a single crystal blade alloy at 760 °C. Ultra-high-resolution chemical mapping reveals that the improvement in creep strength is a result of atomic-scale η (D024) and χ (D019) formation along superlattice stacking faults. To understand these results, the energy differences between the L12 and competing D024 and D019 stacking fault structures and their dependence on composition are computed by density functional theory. This study can help guide researchers to further optimize local phase transformation strengthening mechanisms for alloy development.

Analysis of technical measures for controlling instability of surrounding rock in jointed rock masses

The development and utilization of underground space is an inevitable choice for the development of human society, economic construction, and national security strategy. The failure mechanism of the chamber in underground rock mass engineering is extremely complex, and its stability analysis and control have always been the key problems in the field of rock mechanics. In practical engineering, due to the complexity of the structural plane shape, unreasonable layout, increasing buried depth, and great disturbance of underground rock engineering, the stress concentration in the surrounding rock is intensified, the surrounding rock is extremely sensitive to the change of external load, and the stability state is prone to mutation, resulting in the instability and failure of the chamber structure. In this article, based on the previous theoretical research results and engineering practice experience, the instability control theory of surrounding rock of jointed rock masses on the bases of four basic principles of “consolidating surrounding rock joints, improving surrounding rock strength, restoring and improving stress state, and weakening dynamic disturbance source strength” was proposed. On this basis, to maintain the stability of the surrounding rock of the chamber, the chamber support form of “grouting reinforcement + full-face bolt (mesh) shotcrete combined support + local strengthening support + constructing impact buffer structure + reducing engineering blasting disturbance” was put forward. Moreover, the technical measures for controlling the instability of the surrounding rock of the chamber in jointed rock masses were established, and the technical scheme of joint application and step-by-step implementation was suggested. In addition, the principle of considering the safety and economy of support and the necessity of establishing a multi-parameter real-time joint monitoring and early warning system were discussed. The research results can provide a certain reference for the stability control of surrounding rock in jointed rock masses in similar projects.

Global Contraction and Local Strengthening of Firms’ Supply and Sales Logistics Networks in the Context of COVID-19: Evidence from the Development Zones in Weifang, China

The stagnation of multinational and cross-regional goods circulation has created significant disruptions to manufacturing supply chains due to the outbreak of the COVID-19 pandemic. To explore the impact of COVID-19 on the circulation of manufacturing industry products at different geographical scales, we drew upon a case study of development zones in the city of Weifang in China to analyze the characteristics of firms’ logistics networks in these development zones, and how these characteristics have changed since the outbreak of the COVID-19 pandemic. The data used in this study were collected from fieldwork conducted between 26 August 2020 and 15 October 2020, and included the supply originations of firms’ manufacturing sources and the sales destinations of their goods. We chose the two-mode network analysis method as our study methodology, which separates the logistics networks into supply networks and sales networks. The results show the following: First, the overall structure of firms’ logistics networks in Weifang’s development zones is characterized by localization. In the context of the COVID-19 pandemic, the local network links have further strengthened, whereas the global links have seriously declined. Moreover, the average path length of both the supply and sales logistics networks has slightly decreased, indicating the increased connectivity of the logistics networks. Second, in terms of the network node centrality, the core nodes of the supply logistics networks are the development zones and the city in which the firms are located, whereas the core nodes of the sales logistics networks are the core companies in the development zones. However, since the outbreak of the COVID-19 pandemic, the centrality of supply originations and sales destinations at the local scale has increased, whereas the centrality of supply originations and sales destinations at the global scale has decreased significantly. Third, the influencing factors of such changes include controlling personnel and goods circulation based on national boundaries and administrative boundaries, forcing the logistics networks in the development zones to shrink to the local scale. Moreover, there are differences in the scope of spatial contraction between supply logistics networks and the sales logistics networks.

Using Continuum-Discontinuum Element Method to Model the Foliation-Affected Fracturing in Rock Brazilian Test

In this study, the continuum-discontinuum element method (CDEM) was used to investigate the tensile fracture mechanism of rock materials. An isotropic rock disk model and models considering different foliation inclinations were established, and three schemes were used to simulate the rock fracturing in Brazilian test. Then, the influences of the rock matrix and foliation strengths on anisotropy rock fracturing were investigated. Furtherly, simulation results were verified, and the rock fracture mechanisms were discussed. The results show that the rock fracturing in Brazilian test can be accurately simulated by CDEM, which is in accordance with the experimental results. For isotropic and horizontal foliation rock, the stress concentration in loading positions causes a local fracture of rock sample, and application of a local strengthening scheme can simulate the integral tension fracture of sample middle. As the foliation angle varies from 15° to 45°, the rock fracturing is affected by the stress concentration and foliation distribution. In splitting simulation, a strengthening scheme should be adopted to overcome this influence. As a result, the rock sample generates the sliding and compression-shear fracture. As the foliation angle changes from 45° to 75°, the foliation, rather than the matrix, dominates the fracture behavior of rock sample. For vertical foliations’ rock, as the middle foliation thickness is appropriately broadened, the simulation results are reasonable. In general, the tensile strength of anisotropic rock entirely decreases with an increase of foliation angle, and the effect of foliation strength on the tensile strength rock sample is larger than that of the rock matrix.

Bending behavior of a hot stamped complex phase steel with tailored properties by local carburization

Concerning lightweight design, hot stamping of boron-manganese steels has developed to a state-of-the-art process for manufacturing safety-relevant car body parts in the last two decades. To further improve passenger safety, the idea of components with tailored properties has become even more important. Normally, these process variants aim to bring in so-called soft zones, where a fully martensitic microstructure is prevented to significantly improve ductility. The growing importance of battery electric vehicles and their special requirements call for alternative processes. Especially the battery and its housing are often referred to as a no deformation zone. Concerning this matter, the new process of tailored carburization can be advantageous, since it aims to locally improve strength rather than ductility. Regarding the field of application as a safety-relevant component, the crash behavior is of high interest. In recent years, the three-point bending test has prevailed as a suitable comparative test to estimate crash performance. Within this work, the influence of various carburization parameters on the bending behavior is analyzed. The results reveal that the additional carburization improves punch force at the cost of the bending angle. By analyzing locally carburized samples it is shown, that especially the carburization of the tensile loaded side within the deformation zone is crucial for local strengthening under bending load.

Seismic Evaluation and Retrofit of Reinforced Concrete Buildings with Masonry Infills Based on Material Strain Limit Approach

The seismic evaluation and retrofit of reinforced concrete (RC) structures considering masonry infills is the correct methodology because the infill walls are an essential part of RC structures and increase the stiffness and strength of structures in seismically active areas. A three-dimensional four-storey building with masonry infills has been analyzed with nonlinear static adaptive pushover analysis by using the SeismoStruct software. Two models have been considered in this study: the first model is a full RC-infilled frame and the second model is an open ground storey RC-infilled frame. The infill walls have been modeled as a double strut nonlinear cyclic model. In this study, the “material strain limit approach” is first time used for the seismic evaluation of RC buildings with masonry infills. This method is based on the threshold strain limit of concrete and steel to identify the actual damage scenarios of the structural members of RC structures. The two models of the four-storey RC building have been retrofitted with local and global strengthening techniques (RC-jacketing method and incorporation of infills) as per the requirements of the structure to evaluate their effect on the response reduction factor (R) because the R-factor is an important design tool that shows the level of inelasticity in a structure. A significant increase in the response reduction factor (R) and structural plan density (SPD) has been observed in the case of the open ground storey RC-infilled frame after the retrofit. Thus, this paper aims to present a most effective way for the seismic evaluation and retrofit of any reinforced concrete structure through the material strain limit approach.

Seismic Rehabilitation of Steel Arch Bridges Using Nonlinear Viscous Dampers: Application to a Case Study

AbstractOld steel arch bridges commonly need rehabilitation interventions because of their insufficient lateral resisting capacity against seismic loads. A localized strengthening method is not alw...

Design method for the relocation of plastic hinges in prefabricated steel beams with corrugated webs.

The plastic hinge is a key factor in the ductile and plastic design of structures and an important basis for the seismic strengthening of structures. The formation and behavior of plastic hinges is critical for the seismic performance of an entire structure. The relocation of plastic hinges away from the beam end is an effective way of addressing brittle failure. In this paper, the cause of the shear buckling failure of prefabricated steel beams with corrugated webs and the strain variation at the flanges of steel beams are theoretically analyzed through structural tests. Based on the analysis results, a local strengthening method is proposed, and the effects of the beam sizes and the strengthening steel plate on the plastic hinges are obtained. In addition, a calculation method for determining the size of the strengthening steel plate that promotes the relocation of the plastic zone away from the beam end is given, a design method for plastic hinge relocation is proposed based on the test data, and its validity is verified.

Localization Property for Regular Solutions of the Cauchy Problem for a Fractal Equation of the Integral Form

We consider a fractal equation of the integral form with Bessel fractional integrodifferential operator and a positive parameter. In a part of the initial hyperplane, where the limit value has good properties, we establish the property of local strengthening of the convergence of regular solutions with generalized limit values.

Effect of laser patterning on axial crushing performance of cylindrical 22MnB5 tubes

This paper describes the effects of various laser patterns on as-received 22MnB5 tubes for selective local strengthening. It has been confirmed that strengthened cross-sectional areas, perpendicular to the axial direction by laser patterning, and uniform strength distributions between the as-received and strengthened area can induce the concertina mode under axial crushing. The auxetic and helical laser patterns demonstrated the highest first peaks in the reaction force and substantial energy absorption due to progressive folding, followed by the concertina mode. Considering the fabrication efficiency, the helical pattern is recommended because it can be easily implemented. To optimize the helical pattern design, the specific pitch size should be based on the line length of a single fold along the neutral surface when the as-received tube collapses. Depending on the geometrical dimensions of the tube, this can increase the number of folds and maximise energy absorption by up to 32.2% during axial crushing.

Lateral resistance of OSB sheathed cold-formed steel shear walls

This study experimentally investigated the mechanical properties, failure modes, and lateral resistance of oriented strand board (OSB) sheathed cold-formed steel (CFS) shear walls under monotonic loading and reversed-cyclic loading. The influences of the loading mode, vertical load, ratio and local strengthening of openings, sheathing panel, and diagonal rigid bracing on the lateral resistance of the CFS shear walls were also analyzed. The experimental results demonstrated that the loading mode exerted a significant influence on the performance of the wall panels; the shear resistance of the specimens under monotonic loading was 13% greater than that of the specimens under reversed-cyclic loading. For specimens with the identical configuration, the shear resistance decreased with the opening ratio increasing and local strengthening of openings could reduce the adverse effect. The shear bearing capacity of the single-sided (OSB) panel wall was much greater than that of the non-paneled wall. The vertical load had little influence on the wall's shear bearing capacity. Compared with ordinary CFS shear walls, the walls with V-shaped diagonal rigid bracings demonstrated greater shear bearing capacity and lateral stiffness, whereas the ductility and energy dissipation capacity were comparatively less encouraging.

Effects of exercise training on autonomic modulation and mood symptoms in patients with obstructive sleep apnea.

We evaluated the effects of exercise training (ET) on the profile of mood states (POMS), heart rate variability, spontaneous baroreflex sensitivity (BRS), and sleep disturbance severity in patients with obstructive sleep apnea (OSA). Forty-four patients were randomized into 2 groups, 18 patients completed the untrained period and 16 patients completed the exercise training (ET). Beat-to-beat heart rate and blood pressure were simultaneously collected for 5 min at rest. Heart rate variability (RR interval) was assessed in time domain and frequency domain (FFT spectral analysis). BRS was analyzed with the sequence method, and POMS was analyzed across the 6 categories (tension, depression, hostility, vigor, fatigue, and confusion). ET consisted of 3 weekly sessions of aerobic exercise, local strengthening, and stretching exercises (72 sessions, achieved in 40±3.9 weeks). Baseline parameters were similar between groups. The comparisons between groups showed that the changes in apnea-hypopnea index, arousal index, and O2 desaturation in the exercise group were significantly greater than in the untrained group (P<0.05). The heart rate variability and BRS were significantly higher in the exercise group compared with the untrained group (P<0.05). ET increased peak oxygen uptake (P<0.05) and reduced POMS fatigue (P<0.05). A positive correlation (r=0.60, P<0.02) occurred between changes in the fatigue item and OSA severity. ET improved heart rate variability, BRS, fatigue, and sleep parameters in patients with OSA. These effects were associated with improved sleep parameters, fatigue, and cardiac autonomic modulation, with ET being a possible protective factor against the deleterious effects of hypoxia on these components in patients with OSA.

Triggering mechanism and possible evolution process of the ancient Qingshi landslide in the Three Gorges Reservoir

The Qingshi landslide in the Three Gorges Reservoir was selected as a case study of ancient landslides. The detailed on-site surveys and long-term monitoring data were analysed to classify the triggering mechanism and possible evolution process of the Qingshi landslide. The results show that the ancient Qingshi landslide was triggered by the water storage in 2010. The leading edge slipped first, and the trailing edge underwent large-scale deformation after losing the resistance provided by the leading edge. In early 2011, the compaction of the leading edge of the landslide provided a certain resisting force, which controlled the overall downward movement of the landslide. In 2014, the integrity of the landslide was strengthened by emergency treatment measures, which caused the stabilization of the landslide and further reduced the displacement rate of the landslide. The local strengthening of the leading edge may act as a locking segment that could provide direct support to the sections in the middle and upper parts of the landslide. However, abnormal water-level regulation and heavy rainfall may cause the landslide to collapse again. The entire evolution process of the Qingshi landslide can provide an important reference for ancient landslides located on reservoir banks.

Determination of the parameters of local reinforced zones under the protection means

In order to develop effective measures to ensure the operational condition of the development workings behind the face in the conditions of soft footwall rocks, the construction of local reinforced zones under the protection means has been proposed. The presence of such zones allows transferring the current load deep into the massif and creating a stable foundation under the protective structure. The results of researches concerning establishment of rational parameters of local reinforced zones with application of the method of finite elements, the method of experiment planning and the method of statistical processing of these results have been presented. The empirical dependence of the subsidence of the local reinforced footwall under the protection means on their load, deformation characteristics of the local reinforced zone and host rocks, width of protection means, strength of soft underlying rocks and geometric dimensions of the zone has been determined. The relative indicator of efficiency of local strengthening of a footwall which is used for determining of rational parameters of a locally reinforced zone has been offered.

Structural Behaviors of Integrally-Jointed Plywood Columns with Knot Defects

Modern factory automation is enabling the economic production of timber building components with sophisticated integral mechanical joints. This paper investigates the governing compressive failure mechanisms of full-length integrally-jointed plywood box columns, and in particular seeks to understand the interaction between localized material knot defects, integral box joint capacity, and column strength. A new critical failure mechanism is identified based on experimental observations and numerical analysis of sections with varying sizes of knot defect, with column capacity governed by defect-induced transverse loading of integral box joints. Column capacity was shown to improve with localized joint strengthening in knot-defective regions, or with a defect-adaptive fabrication procedure that avoids identified defects during component plate machining. The new failure mechanism was also combined with prior understanding of plate buckling and pop-off failure mechanisms to propose an overall failure process for integrally-jointed plywood columns. Results from this paper can also inform development of other types of integrally-jointed thin-walled structures.

The estimation of efficiency from application the local strengthening of strip foundations by short piles

Currently many multi-populated Russian cities have an acute shortage of usable space in the central part. The superstructure of one or several floors can become a solution, but it entails a danger of overloading the foundations and the occurrence of uneven precipitation. In this connection, the authors proposed a new model for strengthening the foundations of reconstructed buildings: short piles are pressed or stuffed in local areas, the pile heads are tied with a grillage with the existing foundation. The article discusses the practical and theoretical solution of this problem. Two design models were produced on a 1: 5 scale: a strip foundation model and a strip foundation model locally strengthening with short piles. The experimental results are obtained. A sand base was also calculated using the finite element method by PC PLAXIS. The calculated and experimental data have sufficient convergence of the results. Based on the calculation and experiment, it was found that the draft of the strengthening foundation is 1.875 times less than the draft of the strip foundation, which proves the effectiveness of this method of strengthening with an increase in the load on the foundation by 1.5-2 times.

The Simulation of Aircraft Ditching Based on ALE Method

Ditching is an emergency measure for landing on the water when the aircraft cannot continue to fly in an accident. In order to verify the performance of the aircraft ditching, this paper carry out a simulation study on ditching of fixed-wing aircraft on the water. First determine the simulation method, material model and constitutive equation, and then analyze the influence of the sinking speed and attitude changes on the ditching of the aircraft. The simulation method adopts arbitrary Lagrange-Euler method (ALE). The results show that as the sinking speed increases, the load will increase accordingly. As the initial attitude angle increases, the vertical acceleration gradually decreases, and the longitudinal acceleration is basically the same, the pressure acting area gradually moves backward, and the pressure area gradually decreases. It is necessary to take appropriate local strengthening measures on the dangerous region.