Resistant Capacities Research Articles

Overturning resistant capacities of rocking frames with supplemental vibration control devices under pulse-type excitations

Rocking structures are vulnerable to overturn under earthquake shaking. It is necessary to reduce the overturning probability of rocking structures. Recently, inerters were proposed to control the vibrations of rocking columns, and it was found that the structure equipped with inerter has reduced probability of overturning. However, inerter does not have capacity to dissipate energy, its control performance is believed able to be enhanced once being used in conjunction with dampers. Therefore, this paper approaches rocking structural vibration control from two directions: by applying supplemental inertia and applying supplemental damping to the structure. To this end, inerter, clutched-inerter and viscous damper are selected as control devices, and two combined scenarios are also considered, with configuration Ⅰ consisting of an inerter and a viscous damper in parallel and configuration Ⅱ consisting of a clutched-inerter and a viscous damper in parallel. The analytical models of a rocking frame with supplemental control devices in variable positions are presented and the equations of motion for each model are derived. In addition, the maximum coefficient of restitution of the rocking frame with supplemental control device is derived based on the angular momentum-impulse theorem. The effects and applicable conditions of the considered devices are evaluated by means of assessing the overturning resistances, maximum responses and fragility curves of rocking frames under different conditions. The results show that, with appropriate damping coefficient and apparent mass of the inerter, the combined configurations Ⅰ and Ⅱ provide better control effectiveness than the cases with inerter, clutched-inerter or viscous damper applied individually.

Evaluation of flexural behavior of steel pile connected with clamp-type mechanical connector

Typically, multi-segment steel piles that support loads are connected with mechanical connections or via the welding of segmented sections to ensure support capacity. Because steel piles are often used in the foundations of structures for which the flexural resistance performance requirements are relatively higher than those of pretensioned spun high strength concrete piles, the flexural resistant behavior and capacities of mechanically connected steel piles must be examined. In this study, to confirm the horizontal flexural resistance behavior of the steel piles connected via mechanical connections, a flexural load test of a steel pile connected with the clamp-type connectors was performed, and the flexural resistance behavior and failure characteristics generated in the flexural load state were evaluated. In addition, the mechanical pile connection and steel pile were modeled by finite element (FE) analysis, and the experimental and structural analysis results were compared. The variation in the flexural resistance performance with the changes in the material properties of the steel pile and mechanical connection was analyzed based on the FE analysis results. Taking into account the change in the material properties of the steel pile and clamp-type connectors, it was found that the maximum load and displacement increased with increasing yield and tensile strengths of the clamp-type connector.

Tests on slip resistant behaviour of aluminium alloy-stainless steel faying surfaces

Aluminium alloy-stainless steel structures combine the benefits of high strength-to-weight ratios of aluminium alloys with the excellent ductility of stainless steels. In order to explore the slip resistant aluminium alloy-stainless steel connections, this paper emphasized the surface characteristics and slip resistance of various surface treatments on aluminium alloy and stainless steel plates. Six applicable treatment methods for aluminium alloy-stainless steel slip resistant faying surfaces were experimentally investigated with specifications for the key parameters explored for the treatment procedures. The feasibility of two novel surface treatment methods on aluminium alloy and stainless steel surfaces was evaluated by material tests and the inspection for coatings. The key characteristics of the treated surfaces were comprehensively tested, including the 3D scanned surface topography, measured hardness and roughness. The relationships between the material type, hardness and roughness values under various surface treatments were discussed, which suggested the specific provisions for slip resistant connections in aluminium alloy-stainless steel structures were required. Friction tests of 18 shear connections were conducted to study the friction coefficients of different materials and surface treatments. The impactions of the surface characteristics on slip resistant behaviours of the treated surfaces were analysed. The roughness of the stainless steel surfaces and the hardness of the aluminium alloy surfaces influence the friction coefficients of the examined connections. Through comparative studies, the arc spraying and supersonic cold spraying, as two novel surface treatments, are suggested for the faying surfaces of aluminium alloy-stainless steel shear connections relying on their remarkably high friction coefficients. While the grit blasting and wire brushing also presented pronounced slip resistant capacities among the four examined mechanical surface treatments.

The Disappearance of Rituals: A Topology of the Present by Byung-Chul Han, translated Daniel Steuer, Polity, Cambridge, 2020, pp. 104, £12.99, pbk

The Disappearance of Rituals: A Topology of the Present by Byung-Chul Han, translated Daniel Steuer, <i>Polity</i>, Cambridge, 2020, pp. 104, £12.99, pbk

Aseismic Optimization of Mega-sub Controlled Structures Based on Gaussian Process Surrogate Model

Due to the complex seismic characteristics of mega-sub controlled structures (MSCS), it is difficult to give full play to their advantages in earthquake resistance by traditional design methods. Meta-heuristic optimization algorithms can be used to improve the seismic performance, but the structural response needs to be calculated repeatedly, which results in high computation cost. To overcome these challenges, an efficient aseismic optimization design procedure for engineering application is developed. In this procedure, the model of optimization problem is established based on time history analysis (THA). Gaussian process regression (GPR) surrogate models are employed to predict the values of the objective and constraint functions. The expected improvement (EI) and constrained expected improvement (CEI) criteria are adopted to update the training sample set and obtain the optimal solution. Then, two examples are presented to validate the effectiveness and efficiency of this method in optimization problems of structures under earthquake loads. Finally, it is applied to optimizations of a MSCS and a mega frame structure (MFS), respectively. The response and cost of the optimized structures are reduced, and the MSCS shows better earthquake resistant capacities.

Disaggregated validation of disaster-resilience indicators using household survey data: A case study of Hong Kong

A disaster resilience index aggregates numerous observed individual indicators into a numeric value, for the purpose of gauging various communities’ disparate disaster resilience capacities as part of decision-making in resilience management. There have been abundant studies on the creation of such indices, but only a few have sought to empirically validate individual indicators’ practical efficacy in explaining disaster-related outcomes. Therefore, this study performs such disaggregated empirical validation of nine disaster-resilience indicators’ efficacy at explaining two outcome measures: the resistant capacity and recovery capacity of households in Hong Kong. It reveals that certain indicators including education, income, and place attachment can be empirically valid, but that their explanatory power varies substantially across the two outcome measures. For instance, place attachment has divergent relationships with households’ resistant and recovery capacities. The robustness of the indicators’ explanatory power is also unequal, due to the disparate effect sizes of the outcome measures and the indicators’ interdependence. Based on these findings, we provide recommendations on indicator selection and index creation that should be useful to those seeking to create parsimonious and robust sets of indicators that are explanatory of the actual resilience capacities of local communities.

Peculiarities of the COVID-19 course and consequences in overweight and obese patients. Lessons from the current pandemic

Treatment difficulties of COVID-19 have determined the need to identify predictive risk factors for the development of a complicated disease course, critical conditions and death. Endocrine and metabolic abnormalities associated with obesity, including impaired insulin sensitivity, chronic inflammation and impaired lipid and fatty acid metabolism, increase immunological dysregulation and make these patients more susceptible to developing infectious diseases. Research data allows us to single out obesity as a risk factor for the aggravated course of COVID-19, as well as a longer period before the virus elimination, and, therefore, the risk of virus transmission. Potentiation of cardiovascular risk factors, an increase in the production of pro-inflammatory cytokines, coagulopathy are factors in the development of unfavorable outcomes in such patients.This review presents literature data on the features of the course and the mechanisms of development of complications in patients with new coronavirus infection and obesity. Taking into account the need to restore metabolic health to increase the adaptive and resistant capacities of the body in the face of the threat of a new increase in the prevalence of COVID-19, the possibilities of treating obesity using a combined preparation containing sibutramine and metformin in one tablet, are discussed.

Evaluation method and key factor analysis for thermal protection performance of multifunctional integrated ablative materials

AbstractThe thermal protection materials of hypersonic aircrafts in near space are subjected to extremely serious aerothermodynamic environment under long heating time, higher enthalpy, larger heat accumulation, and so forth. Proposing new concepts of materials and accurate evaluation of their performance take the dominant roles in developing high‐efficiency thermal protection materials under this severe environment. By introducing the concepts of gradient and fiber hybridization, this study proposes a multifunctional integrated ablative material scheme to replace heritage ones in order to improve the heat insulation, ablation resistant, and weight reduction capacities. Meanwhile, a thermal‐fluid‐ablative coupling mathematical model taking the manufacturing processing parameters reflecting the gradient and fiber hybridization into consideration is established. Furthermore, the sensitivity analysis for the manufacturing processing parameters is carried out. A simulation tool is developed based on writing FORTRAN codes to solve the multi‐field coupling model numerically. The results that the model and code are effective in analyzing the material's performance and the key manufacturing processing parameters influencing on the thermal protection performance of multifunctional integrated ablative material are pointed out. This work helps to design new thermal protection materials for hypersonic vehicles under extreme aerothermodynamic environments.Highlights New scheme of multifunctional integrated ablative material is proposed. Developed multi‐field coupling thermal protection model for new material is established. A bridge between material responses and manufacture processing parameters is built. Key factors influencing on material performance are pointed out by sensitivity analysis.

The Innovative Potential of Antibody Engineering Enhanced the Clinical Value of Immunotherapy

The improvements of counter acting antibody generation systems of various types of immunoglobulins have been created on a vast scale. Miscellaneous scientific tools and skills used to design the most efficient and accurate method. The hybridoma innovation opened a new era in the production of antibodies against target antigens of desirable pathogens, life-threatening infections including immune system issue and various intense poisons. Despite that, these clinical acculturated or chimeric murine antibodies have a few constraints and complexities. The study aims to review and explain the advanced antibody engineering to enhance the innovative potential of antibodies. Therefore, our major effort focusing to defeat the current challenges, late advances in hereditary building methods and phage display system that permitted the creation of exceedingly particular recombinant antibodies. These antibodies have been built in the chase for novel remedial medications furnished with improved immune protective capacities. That will potential connects with the resistant effector's capacities; compel advancement of combination proteins, proficient tumor and tissue entrance and high-liking antibodies coordinated against moderated targets. Propelled counteracting agent designing systems have broad applications in the fields of immunology, biotechnology, diagnostics and helpful prescriptions. Even so, there is constrained learning with respect to element immune response improvement approaches. Along these lines, this study reaches outside of our ability to comprehend traditional polyclonal and monoclonal antibodies. Besides, late advances in immunizer designing systems together with counteracting agent sections, show advances, immunomodulation and expansive utilization of antibodies are examined to upgrade creative neutralizer generation in the expedition for a more advantageous future for people.

Traveling the Soil of Worlds: Haunted Forgettings and Opaque Memories

AbstractThis essay works on the role of trauma and forgetting in the subjective formations of the world-traveler andla nueva mestiza. I investigate how forgetting affects the resistant capacities of these figures. I argue throughout that the memory of the world-traveler is an opaque memory, which is unintelligible for the hegemonic demands of transparency, and which forms the silt upon which the resistant possibilities of the world-traveler rest. The first part elaborates María Lugones's conception of world-traveling in relation to Gloria Anzaldúa's New Mestiza consciousness and Mariana Ortega's multiplicitous self. Here I draw attention to the role of opacity and forgetting in the ways in which one can inhabit a world. The second part develops the notions of trauma and haunting to establish the experiential memory of the world-traveler not as a traumatic rupture, but rather as a haunted memory that accompanies her travels. The last section turns to Édouard Glissant's notion of opacity as a resistant mechanism, which works not through the traumatic rupture of experience but rather through sedimentation of experience.

STUDY ON SEISMIC PERFORMANCE AND COLLAPSE-RESISTANT CAPACITY OF TYPICAL FRAME-CORE TUBE STRUCTURES WITH SINGLE AND DUAL LATERAL-FORCE RESISTING SYSTEM

In the design code system of China, frame-core tube structure should be designed as a dual lateral-force resisting system, and there are strict requirements for the secondary lateral-force resisting system of such structure. In other words, the outer frame of the frame-core tube structure should have sufficient lateral stiffness and strength. However, in the design codes of other countries (e.g., ASCE-7 of the United States), the outer frame of the frame-core tube structure is permitted to only carry the vertical load. Therefore, to compare the seismic performances of the single and dual lateral-force resisting systems of the frame-core tube structure, a dual lateral-force resisting system model was firstly designed following the design codes of China. Subsequently, under the same gravity load (and the same concrete consumption), the single lateral-force resisting system model of the frame-core tube structure was design according to the following procedures:1) the secondary lateral-force resisting system was removed from the dual system, and the shear force adjustment of the frame was ignored; 2) the seismic detailing requirement of the frame was lowered to reduce the sectional size. As a result, the tube beared most of the seismic load, and the frame only resisted the vertical load. The structural responses and component damage of these two systems under SLE (Service Level Earthquake) and MCE (Maximal considered earthquake) were analyzed. Furthermore, the collapse mechanisms of two structures and their collapse-resistances were investigated. Finally, the variation of the shear force and shear distribution of the frame under different levels of earthquake and the corresponding damage of key components were discussed. The research shows that the response of the dual system structure was slightly greater than that of the single system, and their collapse resistant capacities were similar. However, the steel consumption of the single system was less than that of the dual system.

Insight on Rosaceae Family with Genome Sequencing and Functional Genomics Perspective.

Rosaceae is one of the important families possessing a variety of diversified plant species. It includes many economically valuable crops that provide nutritional and health benefits for the human. Whole genome sequences of valuable crop plants were released in recent years. Understanding of genomics helps to decipher the plant physiology and developmental process. With the information of cultivating species and its wild relative genomes, genome sequence-based molecular markers and mapping loci for economically important traits can be used to accelerate the genome assisted breeding. Identification and characterization of disease resistant capacities and abiotic stress tolerance related genes are feasible to study across species with genome information. Further breeding studies based on the identification of gene loci for aesthetic values, flowering molecular circuit controls, fruit firmness, nonacid fruits, etc. is required for producing new cultivars with valuable traits. This review discusses the whole genome sequencing reports of Malus, Pyrus, Fragaria, Prunus, and Rosa and status of functional genomics of representative traits in individual crops.

Optimum seismic design of multi-story buildings for increasing collapse resistant capacity

The distribution patterns of equivalent static seismic lateral forces used in current structural design codes are mostly derived from elastic vibration modes. Such force patterns may not be consistent with actual conditions when structures behave into the inelastic range or even into the collapse stage. In this study, a new design method for multi-story buildings that uses an optimum lateral force pattern is proposed based on the concept of uniform damage distribution at the collapse state of these buildings. To reduce the computational cost of statistical analyses for deriving the optimum lateral force pattern, the non-linear story behaviors are represented by a story shear-deformation model with tri-linear relationships. Systematic parametric analyses are performed to study the influences of various ground motion parameters (site condition, magnitude, distance to rupture, and near-fault effect) and structural parameters (number of stories, fundamental period, damping ratio, post-yielding stiffness, ductility, and degrading stiffness) on the optimum lateral force pattern. Formulas for the optimum lateral force pattern that are applicable for practical seismic designs are provided. The collapse resistant capacities of structures designed using the proposed and conventional methods are compared by fragility analyses. Results show that the proposed method increases the seismic collapse resistant capacity of structures under the same construction cost.

Experimental study on the behavior of precast segmental column with domed shear key and unbonded Post-Tensioning tendon under impact loading

Precast segmental columns have been more and more popularly used in constructions of prefabricated reinforced concrete (RC) structures in recent years. During its servicing life the precast segmental column might be subjected to lateral impact loads from hazards such as falling rock and vehicle collision etc., which however has not been well understood. It is therefore necessary to properly understand the response and vulnerability of segmental column under impact loading. A previous experimental study revealed that the trapezoidal prism shear key on concrete segment could effectively reduce lateral slippage between segments under lateral impact loading, but stress concentration near the shear key led to crushing damage to concrete segment. A new shear key design, i.e., domed shear key with smoothed curvature is proposed in this study. Precast segmental columns with domed shear key are fabricated and tested. This paper presents the test results of scaled segmental columns with this new shear key design. The performance of segmental column with the new dome shear key is compared with previously tested columns with trapezoidal shear key and plain segmental column without shear key. Furthermore, the segmental columns with the new domed shear keys were impacted at different locations along the column including the column mid-span, the segmental joint, and the bottom segment to examine the influences of different impact locations on their impact resistant capacities, and the response and failure modes.

Probiotics and Chronic Liver Diseases

Probiotics and Chronic Liver Diseases

Empirical Fragility Curves of Buildings in Northern Miyagi Prefecture During the 2011 off the Pacific Coast of Tohoku Earthquake

In this study, empirical fragility curves expressed in terms of relationship between damage ratio indices of buildings and ground motion indices were developed in northern Miyagi prefecture located in near-field areas during the 2011 off the Pacific coast of Tohoku Earthquake. The ground motion indices were evaluated from observed ground motions at strong-motion stations and estimated at sites at which no strong-motion accelerometers were deployed during the mainshock. The ground motions at the non-instrumental sites were estimated using the empirical Green’s function method based on bedrock motions inverted from observed records on surfaces from small events that occurred inside the source fault, transfer functions due to underground velocity structures identified from microtremor H/V spectral ratios, and a short-period source model of the mainshock. The findings indicated that the empirical fragility curves as functions of Japan Meteorological Agency (JMA) instrumental seismic intensity during the 2011 Tohoku Earthquake almost corresponded to those during the 1995 Kobe Earthquake and the seven disastrous earthquakes that occurred between 2003 and 2008. However, the empirical fragility curves as functions of peak ground velocity were the lowest. A possible reason for this is that the response spectra of the ground motions in the period ranging from 1.0 s to 1.5 s were small during the 2011 Tohoku Earthquake. Another reason could be the seismic resistant capacities of buildings in the studied districts involved during the 2011 Tohoku Earthquake exceeded those in the cities affected during the 1995 Kobe Earthquake.

Experimental and analytical analysis of reinforced concrete columns strengthened with CFRP

The technology of the Construction Industry is advancing constantly. Every year, new materials, equipment, and building techniques are introduced. In the specific case of reinforced and pre-stressed concrete structures, the innovations have contributed to the improvement of the properties of the concrete and the durability of the structures that incorporate this material. These advances are not restricted to the construction of new structures, however, and it is important to recognize the need to recuperate structural elements or increase their resistance, which has provided incentives for the improvement of techniques of structural reinforcement. In this context, the present study used a combined theoretical and experimental approach for the investigation of the effectiveness of the reinforcement of concrete columns by jacketing them with polymer mantles strengthened with carbon fibers. The analyses aimed to determine the effectiveness of the mantles in terms of the increase in resistance to axial compression and contribute to the understanding of the structural behavior of columns strengthened using this technique. To this end, centered axial compression tests were run on five short reinforced concrete columns, including one control column and four experimental columns with different reinforcement ratios. Numerical simulations were also run in the Abaqus software to determine the distribution of tensions inside the columns. The sum of the evidence was analyzed and it was verified that the strengthening used in the columns increased considerably their resistant capacities, thus the gain in this capacity was directly proportional to the value of the used strengthening rate—the column with the biggest strengthening rate bore a last load 42.8 % bigger than the one borne by the column of reference, with no strengthening. From these data, it was possible to obtain a simple predictive model of the increase in resistance capacity of columns strengthened with carbon fibers.

Sisal Fiber as Steel Bar Replacement of Lightweight Concrete under Flexural Loading

The potential of natural resources such as pumice and sisal fiber for simple housing structural components is investigated in this research. Behavior of sisal fiber reinforcement of lightweight concrete beam under flexural loading was examined. The purpose of this study is to identify the prospect of sisal fiber as a replacement of steel bar reinforcement for structural element. The variations of reinforcement ratios were considered in order to optimize the performance of sisal fiber reinforcement. Twelve beam specimens size 100 x 150 mm with clean span of 1.5 m were examined in this investigation. Four variations of beam reinforcement were explored consist of 3 sisal fiber variation and 1 steel reinforcement as a control; where every variation was presented with three samples. Enerpac hydraulics Jack with 50 ton capacity connected to the load cell was operated as a source of loading. LVDT was fitted in the mid-span to measure vertical deflections during the loading. Test results indicated that the crack moment experiments were higher than the crack moment calculations. The valued were 1.44, 1.52, and 2.72 higher for sisal fiber reinforcement of B-LF, B-MF and B-HF, respectively. Whilst for steel reinforcement of B-LS the valued were 3.32 higher. Observation results also indicated that the moment resistant capacities of the specimens were twice higher compare to the calculated moment capacity. However, The lowest sisal reinforcement (B-LF) has only about 10% different service moment compare to the steel reinforcement (B-LS) where they both have equal ρ = 1.206 %. This indicate that the use of sisal fiber have considered as insignificant different service moment capacity to the steel reinforcement.

Effect of Al2Gd on microstructure and properties of laser clad Mg–Al–Gd coatings

In order to investigate the effects of Gd addition on the microstructures and properties of magnesium coatings, the Mg–7.5Al–xGd (x=0, 2.5, 5.0 and 7.5wt.%) coatings on cast magnesium alloy were fabricated by laser cladding with wire feeding. The results indicated that the gadolinium (Gd) addition led to the formation of a cubic Al2Gd phase as well as suppressed the precipitation of eutectic Mg17Al12 phase. The laser clad coating containing nominally 7.5wt.% Gd presented the highest microhardness, ultimate tensile strength and yield strength at both room temperature and high temperatures. The enhancement of heat resistant capacities was chiefly attributed to the existence of thermally stable Al2Gd particles, which prevented tiny liquation of eutectic phases along the grain boundaries and made great contributions on maintaining high yield ratio during high-temperature deformation.

平面ラチス梁の終局耐震性能に及ぼす静的安全率の効果

Earthquake input energies have been discussed in considering seismic resistant capacities of structures. In the literature, it had been pointed out by the author et al. that potential energies due to self-weight and dead loads would be necessary to be taken into account in order to estimate the seismic resistance capacity in a good accuracy especially for beam type structures. The author presented an estimation method of ultimate seismic resistance capacity with the static absorbed energies considering potential energies. The method presented utilizes the two strain energies at an initial yield and a limit state, and a pseudo velocity response spectrum of seismic waves. Although it is based on an extrapolation method, it shows a good accuracy in the estimation of maximum input acceleration of seismic waves. The method includes a modification equation to improve the accuracy, considering the properties of elastic and plastic strain energies of structures during a pushover analysis. Then in this paper, the effect of static safety factors is investigated to make clear the meanings of coefficient in the modification equation, for lattice beams of two types, cross web type and warren type. As the results, a further modified estimation method is presented to predict the dynamic collapse level under excessive seismic motions with the information of pushover and free vibration analyses.