Weak Region Research Articles

A modeling strategy for the flexural performance prediction of UHPC beams accounting for variability of properties

The Reinforcing Ratio (RR) is a major factor governing the ductility of UHPC beams. Previous works have demonstrated that beams with low RR (less than2.0 %) exhibit a sudden drop in load after the peak. The first part of the present paper reports the results of an experimental program comparing the responses of beams made with conventional concrete and UHPC for two different RR (0.44 % and 1.78 %). The results confirm that UHPC increases the load-carrying capacity by up to 135 %, allowing for multiple cracking with finer cracks. Using the post-peak drift method, it is shown that the ductility of the UHPC beams with RR = 1.78 % was about 2.6 times greater than that for RR = 0.44 %. In the second part of the work, a numerical finite element modeling strategy accounting for the inhomogeneous fiber distribution is developed and validated against the experiments. It is shown that the homogenous models cannot simulate the crack localization associated with weak regions in UHPC and, therefore, overpredict member ductility. Finally, the numerical model is used to design optimized UHPC beams with the same strength as the tested reinforced concrete beams. It is shown that half of the cross-section width is necessary, resulting in greater RR values that ultimately increase the ductility by 275 % and 167 %, respectively, for beams reinforced with RR = 0.44 % and 1.78 %.

Adaptive Backstepping Integral Sliding Mode Control of a MIMO Separately Excited DC Motor

This research proposes a robust nonlinear hybrid control approach to the speed control of a multi-input-and-multi-output separately excited DC motor (SEDCM). The motor that was under consideration experienced parametric uncertainties and load disturbances in the weak field region. The proposed technique aims to merge the benefits of adaptive backstepping (AB) and integral sliding mode control (ISMC) to enhance the overall system’s robustness. The unknown parameters with load disturbances are estimated using an adaptation law. These estimated parameters are incorporated into the controller design, to achieve a highly robust controller. The theoretical stability of the system is proved using the Lyapunov stability criteria. The effectiveness of the proposed AB–ISMC was demonstrated by simulation, to track the reference speed under parametric uncertainties and load disturbances. The control performance of the proposed technique was compared to that of feedback linearization (FBL), conventional sliding mode control (SMC), and AB control laws without and with the adaptation law. Regression parameters, such as integral square error, integral absolute error, and integral time absolute error, were calculated to quantitatively analyze the tracking performance and robustness of the implemented nonlinear control techniques. The simulation results demonstrated that the proposed controller could accurately track the reference speed and exhibited robustness, with steady-state error accuracy. Moreover, AB–ISMC overperformed, compared to the FBL, SMC, AB controller without adaptation law and AB controller with adaptation law, in reducing the settling time by factors of 27%, 67%, 23%, and 21%, respectively, thus highlighting the superior performance of the proposed controller.

Experimental and numerical study on shear behavior of shear pockets between ultra-high-performance and normal concrete for precast girder bridges

Ultra-high-performance concrete (UHPC) has been widely utilized in precast bridge girders as a new material to reduce structural self-weight and improve constructional efficiency. Typically, UHPC and normal concrete (NC) are implemented to construct precast girders and deck, respectively, and cast-in-place shear pockets are used to connect these two. However, these shear pockets are vulnerable components that affect the integrity of UHPC-NC bridge superstructure. Thus, to comprehensively and deeply investigate the shear performance of shear pockets, a push-off test on block specimens and a bending test on a scaled bridge superstructure are conducted in this study. In addition, A refined finite element model (FEM) is proposed for UHPC-NC interface, which incorporates the effects of cohesion, dowel action of reinforcement and frictional force. The accuracy of the proposed FEM is validated against experimental data. Besides, the code equations are evaluated by push-off test results. The push-off test results verify that reinforcement across the interface plays a critical role in enhancing the shear strength between UHPC and NC, and NC is a weak region for the UHPC-NC interface, which should be paid much attention when designing. The experimental and numerical results of the bending specimen indicate that NC deck and UHPC girder connected by shear pockets with shear reinforcement can satisfy the performance requirements of a bridge girder, showing satisfactory integrity for UHPC and NC members under flexure. Furthermore, design equations specified in ACI318R-19, AASHTO, MC-10 and Eurocode 4 can provide a satisfactory prediction of shear strength at UHPC-NC interface, as demonstrated by comparing with experimental results.

Significant Progress for Hot-Deformed Nd-Fe-B Magnets: A Review.

High-performance Nd-Fe-B-based rare-earth permanent magnets play a crucial role in the application of traction motors equipped in new energy automobiles. In particular, the anisotropic hot-deformed (HD) Nd-Fe-B magnets prepared by the hot-press and hot-deformation process show great potential in achieving high coercivity due to their fine grain sizes of 200-400 nm, which are smaller by more than an order of magnitude compared to the traditional sintered Nd-Fe-B magnets. However, the current available coercivity of HD magnets is not as high as expected according to an empirical correlation between coercivity and grain size, only occupying about 25% of its full potential of the anisotropy field of the Nd2Fe14B phase. For the sake of achieving high-coercivity HD magnets, two major routes have been developed, namely the grain boundary diffusion process (GBDP) and the dual alloy diffusion process (DADP). In this review, the fundamentals and development of the HD Nd-Fe-B magnets are comprehensively summarized and discussed based on worldwide scientific research. The advances in the GBDP and DADP are investigated and summarized based on the latest progress and results. Additionally, the mechanisms of coercivity enhancement are discussed based on the numerous results of micromagnetic simulations to understand the structure-property relationships of the HD Nd-Fe-B magnets. Lastly, the magnetization reversal behaviors, based on the observation of magneto-optic Kerr effect microscopy, are analyzed to pinpoint the weak regions in the microstructure of the HD Nd-Fe-B magnets.

The Effect of Working Length, Fracture, and Screw Configuration on Plate Strain in a 3.5-mm LCP Bone Model of Comminuted Fractures

Abstract Introduction This study provides a comprehensive examination of plate strain under realistic fracture configurations. The effect of plate working length, plate contact, fracture length, and position on strain was evaluated using bone surrogates subjected to “load-controlled,” nondestructive conditions. Materials and Methods Five 3.5-mm locking compression plates (LCP) were instrumented with six strain gauges. The gauges were glued between holes in predetermined locations marked by laser engraving. Nine fracture models were created using bone surrogate, each representing a combination of the criteria under study: long versus short working length, degree of plate compression, fracture location, and fracture length. All five plates were tested under each of the nine configurations. The constructs were mounted in an Instron testing machine with a 5-kN load cell. Each specimen was cyclically loaded at a rate of 5 mm/min to 50, 100, and 200 N. Results Decreased plate strain was noted with a short plate working length in all fracture configurations (p < 0.05). Increasing the plate working length increased the strain at higher loads and on the plate adjacent to the fracture gap. The size of the fracture gap and fracture location had minimal effects on plate strain (p < 0.05). Elevation of the plate off the bone (1.5 mm) resulted in increased plate strain under all loading conditions (p < 0.05). Conclusion Our null hypothesis was rejected in that a short plate working length resulted in decreased plate strain in all comminuted fracture configurations. Our secondary hypothesis was validated in that elevation of the plate from the bone resulted in increased strain in all configurations. As plate strain identifies regions of mechanical weakness whereby a construct may prematurely fail by acute overload or cyclic fatigue, identifying factors that may increase plate strain allows the surgeon to reduce these variables as much as possible to reduce the incidence of implant failure and subsequent fracture failure.

Exact Treatment of the Infinite Square Well in One Dimension with λδ^' (x) Potential

Abstract: This work considered the infinite square well in one dimension with a contact potential. The Dirac delta derivative function potential λδ^' where λ is a coupling constant was used to represent the contact potential. Using Green’s function technique, exact implicit expressions of the energy eigenvalues and eigenfunctions were obtained. The energy eigenvalues were expressed using a transcendental equation. The energy eigenfunctions satisfy the Schrödinger equation and the infinite square well boundary conditions. Also, the eigenfunctions and their first derivative were shown to be discontinuous. The values of these discontinuity jumps agreed with the required conditions for a self-adjoint extension Hamiltonian. In the weak coupling region, the energy eigenvalues are close to that of the even parity solution before adding the contact potential. The energy eigenvalues in the strong coupling regime reveal the energy eigenvalues of the odd parity solution. Keywords: Point interactions, Infinite square well, Green’s function technique. PACS numbers: 03.65.-w, 03.65.Db, 03.65.Ge

Design and optimization of an electrostatic fog collection system for water harvesting: Modeling and experimental investigation

Electrostatic fog collection presents a promising solution for addressing water scarcity by recovering water from fog. This study proposed a multi-channel electrostatic fog collector that utilizes multiwire-to-plate electrodes. Through numerical simulations, the charging and migration mechanisms of fog droplets were revealed. Additionally, the influence of electrode structure parameters on the electrostatic fog collection process was analyzed. Results show that during the charging process, droplet charge rapidly approaches saturation near the wire electrodes. Moreover, the fog collection efficiency increases with an increase in working voltage, but the growth rate decreases gradually at high voltage. The wire interval and wire-plate gap determine the electric field distribution, which in turn affects the collection efficiency. The effect of wire interval and wire-plate gap on the electric field distribution could be categorized into three zones: the insensitive region, the weak influence region, and the strong influence region. The simulation results show that the optimal range of the dimensionless wire interval falls in the weak influence region, specifically in the range of 0.8 ≤ S/G ≤ 1.6, where S/G represents the ratio of wire interval to wire-plate gap. The experimental results demonstrate that the electrostatic fog collector within this range can achieve a water collection rate of 123.7 g/min at 20 kV. The corresponding performance coefficient is 388.7 kg/kWh, which exceeds the 200–333.3 kg/kWh performance coefficient of commonly used commercial reverse osmosis desalination technology. These findings provide direction for the practical application of electrostatic fog collection technology.

Harnessing buckling response to design lattice structures with improved buckling strength

Lattice structures (LSs) are suitable for engineering structures because of their exceptional mechanical properties. However, strut based LSs suffer from a low buckling strength that limits their effectiveness in structural applications requiring high stiffness and strength. We propose a novel method for designing buckling-resistant strut-based LS by harnessing the buckling response of the base LS. A simple cubic strut LS with square cross-section struts was investigated with its buckling modes as a guide to design modified stiffened LS while maintaining the same relative density and stiffness. The weak regions in the LS were modified using conventional geometries, such as hollow rectangular, hollow hexagonal and angle designs. Experimental analysis of additively manufactured LS demonstrates increase in the buckling strength of up to 35% can be achieved without compromising the stiffness of the LS. The numerical simulations are further validated with experimental results with discrepancy below 10%. Finally, it was also found that the trends in the buckling strength were consistent for samples based on different relative densities and independent of material type. These results demonstrate that the current methodology can be further extended to other LSs to enhance their buckling resistance without reducing the stiffness of the base LSs.

Study on the Difference of Wavefront Distortion on Beams Caused by Wavelength Differences in Weak Turbulence Region

In dual-wavelength free-space optical communication systems, the wavefront distortion differences caused by the wavelength difference of the signal and beacon lights cannot be completely corrected. In this study, according to the method of geometric optics, the relationship between the wavefront phases of the signal and beacon lights is analyzed by establishing a mathematical model of the cross-correlation ratio of the arrival-angle fluctuation and phase relationship of different Gaussian-beam wavelengths under weak turbulence near the surface. The numerical results show that after Gaussian beams of different wavelengths propagate through the same atmospheric channel, the cross-correlation number of the arrival-angle fluctuation decreases with an increase in the wavelength difference, waist radius, and turbulence intensity, and increases with an increase in propagation distance. The beam-wavefront phase difference increases with an increasing wavelength difference. Finally, a wavefront distortion correction experiment of a dual-wavelength adaptive optical system verified the correctness of the wavefront phase-difference relationship between the signal light and beacon light established in this study.

Predicting hourly electricity consumption of chillers in subway stations: A comparison of support vector machine and different artificial neural networks

It is essential to predicting the electricity consumption of air-conditioning systems. In this study, three models, namely, backpropagation neural network (BPNN), cascade correlation neural network (CCNN), and support vector regression (SVR), were proposed for the prediction of the electricity consumption of chillers in subway stations. For demonstration, historical data from a subway station in Guangzhou were used for training and testing. The simulation results showed that the proposed models could predict the electricity consumption of chillers effectively. In comparison with BPNN, CCNN and SVR showed higher accuracy. For the refrigeration of public spaces (PSs), weak electricity regions (WERs), and comprehensive management regions (CMRs), CCNN exhibited the minimum mean absolute percentage error (MAPE) and root-mean-square error (RMSE) for the test samples, the values of which were 1.56% and 3.15, respectively, followed by those of SVR and BPNN. For the refrigeration of strong electricity regions (SERs), PSs, WERs, and CMRs, SVR presented the smallest error, and its MAPE and RMSE for the test samples were 2.01% and 6.09, respectively, followed by those of CCNN and BPNN. Through the comprehensive consideration of input characteristics, the comparison of different prediction models and the distinction of different operating conditions, the prediction accuracy was improved effectively. Based on the forecasting, the operational parameters of the air-conditioning system can be optimized in advance, which is of great significance for energy saving in subway stations.

Contribution of Processes in SN Electrodes to the Transport Properties of SN-N-NS Josephson Junctions.

In this paper, we present a theoretical study of electronic transport in planar Josephson Superconductor-Normal Metal-Superconductor (SN-N-NS) bridges with arbitrary transparency of the SN interfaces. We formulate and solve the two-dimensional problem of finding the spatial distribution of the supercurrent in the SN electrodes. This allows us to determine the scale of the weak coupling region in the SN-N-NS bridges, i.e., to describe this structure as a serial connection between the Josephson contact and the linear inductance of the current-carrying electrodes. We show that the presence of a two-dimensional spatial current distribution in the SN electrodes leads to a modification of the current-phase relation and the critical current magnitude of the bridges. In particular, the critical current decreases as the overlap area of the SN parts of the electrodes decreases. We show that this is accompanied by a transformation of the SN-N-NS structure from an SNS-type weak link to a double-barrier SINIS contact. In addition, we find the range of interface transparency in order to optimise device performance. The features we have discovered should have a significant impact on the operation of small-scale superconducting electronic devices, and should be taken into account in their design.

Level pinning of anti-PT-symmetric circuits for efficient wireless power transfer.

Wireless power transfer (WPT) technology based on magnetic resonance (a basic physical phenomenon) can directly transfer energy from the source to the load without wires and other physical contacts, and has been successfully applied to implantable medical devices, electric vehicles, robotic arms and other fields. However, due to the frequency splitting of near-field coupling, the resonant WPT system has some unique limitations, such as poor transmission stability and low efficiency. Here, we propose anti-resonance with level pinning for high-performance WPT. By introducing the anti-resonance mode into the basic WPT platform, we uncover the competition between dissipative coupling and coherent coupling to achieve novel level pinning, and construct an effective anti-parity-time (anti-PT)-symmetric non-Hermitian system that is superior to previous PT-symmetric WPT schemes. On the one hand, the eigenvalue of the anti-PT-symmetric system at resonance frequency is always pure real in both strong and weak coupling regions, and can be used to overcome the transmission efficiency decrease caused by weak coupling, as brought about by, for example, a large size ratio of the transmitter to receiver, or a long transmission distance. On the other hand, due to the level pinning effect of the two kinds of coupling mechanisms, the working frequency of the system is guaranteed to be locked, so frequency tracking is not required when the position and size of the receiver change. Even if the system deviates from the matching condition, an efficient WPT can be realized, thereby demonstrating the robustness of the level pinning. The experimental results show that when the size ratio of the transmitter coil to the receiver coil is 4.29 (which is in the weak coupling region), the transfer efficiency of the anti-PT-symmetric system is nearly 4.3 (3.2) times higher than that of the PT-symmetric system when the matching conditions are satisfied (deviated). With the miniaturization and integration of devices in mind, a synthetic anti-PT-symmetric system is used to realize a robust WPT. Anti-PT-symmetric WPT technology based on the synthetic dimension not only provides a good research platform for the study of abundant non-Hermitian physics, but also provides a means of going beyond traditional near-field applications with resonance mechanisms, such as resonance imaging, wireless sensing and photonic routing.

Numerical simulation of wind-induced load on evacuated tube solar water heaters

Solar Water Heater (SWH) has been used as a traditional device in many countries and regions for collecting solar energy. Unfortunately, there are many wind-induced accidents of SWHs, owing to insufficient consideration of wind-resistant design and installation. To better promote the safe use of SWHs, characteristics of wind load acting on them should be clarified thoroughly as far as possible. In this article, a systematic study is carried out by numerical simulation based on computational fluid dynamics (CFD) to analyze the effects of the tilt angle and density of evacuated tube collectors (ETC) as well as wind direction on the aerodynamic characteristics of SWH. Results show that the wind-resistance performance of SWH decreases significantly for wind flows blowing from 0° and 180° due to the influence of aerodynamic characteristics of its main components. When the ETC is located upstream of the water tank, the arrangement form of the tubes will have an impact on the aerodynamic characteristics of the SHW. A lower porosity of ETC can increase wind load on the weak region of water tank and the windward face of vertical supports, it can also increase the bending moment of inclined supports significantly. By contrast, lower tilt angles of ETC are more beneficial to the wind resistance of SHW, although they can result in an increase of the local wind suction on water tank.

Response of Masonry-Infilled Reinforced Concrete Frames Strengthened at Interfaces with Geo-Fabric under In-Plane Loads

The interfaces between masonry infill and reinforced concrete (MI-RC) frames are identified as the weakest regions under lateral loads. Hence, the behavior of such frames under lateral loads can be understood mainly through experimental investigations. The deformation demands induced by horizontal loads on RC frames with infill masonry walls change due to contact losses between the infill masonry and the RC frames. This can be controlled by providing proper reinforcements at the interfaces. In the present experimental investigation, three half-scaled models subjected to reversed cyclic lateral in-plane loads were tested. In detail, the specimens considered are the MI-RC frame model, an MI-RC frame with geo-fabric reinforcement at the interface and an MI-RC frame with geo-fabric reinforcement at interfaces with an open ground story. The models were subjected to reversed cyclic lateral in-plane loads, and the post-yield responses of the models with respect to stiffness degradation, drift, energy dissipation, ductility and failure mode have been discussed.

SINE Insertion in the Pig Carbonic Anhydrase 5B (CA5B) Gene Is Associated with Changes in Gene Expression and Phenotypic Variation.

Transposons are genetic elements that are present in mammalian genomes and occupy a large proportion of the pig genome, with retrotransposons being the most abundant. In a previous study, it was found that a SINE retrotransposon was inserted in the 1st intron of the CA5B gene in pigs, and the present study aimed to investigate the SINE insertion polymorphism in this gene in different pig breeds. Polymerase chain reaction (PCR) was used to confirm the polymorphism in 11 pig breeds and wild boars), and it was found that there was moderate polymorphism information content in 9 of the breeds. Further investigation in cell experiments revealed that the 330 bp SINE insertion in the RIP-CA5B site promoted expression activity in the weak promoter region of this site. Additionally, an enhancer verification vector experiment showed that the 330 bp SINE sequence acted as an enhancer on the core promoter region upstream of the CA5B gene region. The expression of CA5B in adipose tissue (back fat and leaf fat) in individuals with the (SINE+/+) genotype was significantly higher than those with (SINE+/-) and (SINE-/-) genotypes. The association analysis revealed that the (SINE+/+) genotype was significantly associated with a higher back fat thickness than the (SINE-/-) genotype. Moreover, it was observed that the insertion of SINE at the RIP-CA5B site carried ATTT repeats, and three types of (ATTT) repeats were identified among different individuals/breeds (i.e., (ATTT)4, (ATTT)6 and (ATTT)9). Overall, the study provides insights into the genetic basis of adipose tissue development in pigs and highlights the role of a SINE insertion in the CA5B gene in this process.

Robustness of Wireless Power Transfer Systems with Parity-Time Symmetry and Asymmetry

Recently, wireless power transfer (WPT) technology has attracted much attention and shown rapid development. However, a fundamental challenge emerges in practical applications: how to achieve robust power transfer against the variation of operating conditions, such as the fluctuation of transfer distance, as well as the relative orientation of resonant coils. In this article, we theoretically propose and experimentally demonstrate that the robustness of a parity-time (PT) asymmetric system with unbalanced gain-loss working in a weak coupling region can be improved significantly, compared with that of a PT-symmetric system with balanced gain-loss working in a strong coupling region under the premise that the system works at a fixed optimal frequency. A pure real mode known as bound state in the continuum (BIC) in the weak coupling region of the PT-asymmetric system is adopted to ensure the high efficiency and stability of the WPT and break the limitations of balanced gain-loss of the PT-symmetric system. The better robustness performance originates from the orthogonal state with a pure real eigenmode embedded in the weak coupling region. Further experiments also verify that the PT-asymmetric system can achieve higher efficiency than that of the PT-symmetric system. In addition, we discuss the performance of the WPT system based on the theories of coupled mode theory (CMT) and circuit theory (CT); the BIC in the framework of CMT and a perfect impedance matching condition in the framework of CT for efficient power transfer are consistent. We also conducted power experimental verification of 30 watts, and found the efficiency between the coils can reach over 90% in dynamic scenarios, which meets expectations. The presented framework extends the field of non-Hermitian physics, bridges the gap between the non-ideal PT-symmetric system and a practical engineering application, and introduces a novel WPT mechanism for flexible application scenarios. Our results could provide instructive significance for practical applications of the WPT system in the long term.

Enzyme Stability-Activity Trade-Off: New Insights from Protein Stability Weaknesses and Evolutionary Conservation.

A general limitation of the use of enzymes in biotechnological processes under sometimes nonphysiological conditions is the complex interplay between two key quantities, enzyme activity and stability, where the increase of one is often associated with the decrease of the other. A precise stability-activity trade-off is necessary for the enzymes to be fully functional, but its weight in different protein regions and its dependence on environmental conditions is not yet elucidated. To advance this issue, we used the formalism that we have recently developed to effectively identify stability strength and weakness regions in protein structures and applied it to a large set of globular enzymes with known experimental structure and catalytic sites. Our analysis showed a striking oscillatory pattern of free energy compensation centered on the catalytic region. Indeed, catalytic residues are usually nonoptimal with respect to stability, but residues in the first shell around the catalytic site are, on the average, stability strengths and thus compensate for this lack of stability; residues in the second shell are weaker again, and so on. This trend is consistent across all enzyme families. It is accompanied by a similar, but less pronounced, pattern of residue conservation across evolution. In addition, we analyzed cold- and heat-adapted enzymes separately and highlighted different patterns of stability strengths and weaknesses, which provide insight into the longstanding problem of catalytic rate enhancement in cold environments. The successful comparison of our stability and conservation results with experimental fitness data, obtained by deep mutagenesis scanning, led us to propose criteria for improving catalytic activity while maintaining enzyme stability, a key goal in enzyme design.

Giant hail in Poland produced by a supercell merger in extreme instability – A sign of a warming climate?

Severe thunderstorms that occurred on 11 June 2019 over eastern Germany and western Poland caused severe material losses primarily due to large hail. This work documents a detailed inventorization of 79 large hail reports collected in the densely populated area of Gorzów Wielkopolski in Poland, including the largest with a diameter of 12 cm and heaviest with a weight of 380 g. Evaluation of environmental and Doppler radar data indicate that three unique aspects characterize this event. Firstly, the storm benefited from a favorable convective environment including a record-high CAPE exceeding 4000 J kg−1 that was the highest ever measured value at a proximity rawinsonde station of Lindenberg, and the highest for this region according to ERA5 since 1950. Secondly, moisture pooling along the convergence zone led to convective initiation of 3 isolated cells that merged together. Two of them with already embedded rotation. This merger subsequently evolved into a single powerful mesocyclone that was a main cause of giant hail. Subtle differences in the orography within Warta river valley could have played a role in the merging process. Third, a supercell had the biggest intensity over a densely populated area, which led to considerable material losses, but also allowed collection of a large number of hail reports. Distribution of these reports indicates that peak hail size varied significantly on very small distances. Storm has been producing giant hail for around 20-min over a distance of around 10 km and was preceded by a well-developed velocity couplet, bounded weak echo region and hook-echo signatures on the Doppler radar scans.

Analysis of a Soil Structure Interaction Technique Considering Lateral Load Effect Using Analysis Tool: A Review

Presently a day the human existence and the climate have regularly been imperiled by the normal dangers like seismic tremor, wave, flood, tornado and avalanches. As a result of which the human culture and the country's economy get hampered following the event of a catastrophic event. In emerging nations like India, where the populace is extremely enormous and is expanding step by step, the social and financial variables force individuals to reside in weak regions, because of which the impacts of these cataclysmic events are disastrous. Among this large number of dangers, liquefaction of soil can be called attention to as perhaps of the most appalling seismic peril. Consequently assessment of liquefaction vulnerability is a significant part of geotechnical designing. Soil-structure communication impact in the examination and plan of RC outline structures is progressively perceived yet at the same time not entered to the grass root level inferable from different intricacies included. It is deeply grounded reality that the dirt construction collaboration impact significantly impact the plan of multi-story structures exposed to parallel seismic burdens. Key Word: Analysis, Structure, Stress, Soil, Lateral Load.

Transport and recombination properties of doped SiC nanoribbons with different atoms substituted by group-V elements

Based on semiconductor theory and optimization data derived from first-principles, we simulate the conductive and recombination properties of group-V doped zigzag SiCNRs (ZSiCNRs), through in-depth analysis of different substitutional doping models, to unveiling the mechanism of carrier transport in nanodevices. It’s found that though there are two impurity energy levels whether C or Si is substituted in doped ZSiCNRs, the conductivity is significantly larger for Si atom substituted than that of C atom replacement. Besides, different temperature dependent conductivity characters are exhibited in the weak and strong ionization regions, indicating the differences in dominant factor for the transport processes. The temperature-dependent holes trapping rate of carrier recombination increased sharply for C or Si atom substitution, indicating a negative temperature-dependence of lifetime of non-equilibrium minority carrier for doped ZSiCNRs. Further, the non-equilibrium minority carrier lifetime is longer with small injection due to the presence of donor impurities in group-V doped ZSiCNRs.