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This paper presents the results of an investigation of dynamic behaviours of strengthened adobe structures. These structures were strengthened using two different schemes which were inexpensive and simple to apply. The dynamic testing was carried out on a shaking table which applied the loading corresponding to the 1995 Kobe earthquake record sequentially in increments of 25%. The structural damage to a model was divided into different damage grades using a quantitative measure of vulnerability. Although some differences were observed in the stiffness of the models in their undamaged state, the stiffness of both of them became similar in the damaged state. The changes in the fundamental frequency of the structure corresponded to the changes in the stiffness. The difference in the base shear demand of both models did not exceed more than 15%. The hysteresis loops of the tested structures turned non-symmetric at a peak ground acceleration of nearly 1.10 g. The models exhibited higher lateral load capacities in one direction of loading as compared to the other direction. The ductility and energy dissipation were also higher in one direction of loading. The performance of the tested structures was categorised into four performance levels and the data of drift, ductility, damping and period corresponding to each level have been reported. [ABSTRACT FROM AUTHOR]

This paper discusses the iteration of a seismic retrofit solution for shear-deficient end regions of 19 reinforced concrete (RC) moment-resisting frame (MRF) T-beams located in a 12-story RC MRF building in downtown Los Angeles, California. Local strengthening with externally bonded (EB) fiber-reinforced polymer (FRP) fabric was chosen as the preferred retrofit strategy due to its cost-effectiveness and proven performance. The FRP-shear-strengthening scheme for the deficient end-hinging regions of the MRF beams was designed and evaluated through large-scale cyclic testing of three replica specimens. The specimens were constructed at 4/5 scale and cantilever T-beam configurations with lengths of 3.40 m or 3.17 m. The cross-sectional geometry was 0.98 × 0.61 m with a top slab of 1.59 m in width and 0.12 m in thickness. Applied to these specimens were three different retrofit configurations, tested sequentially, namely: (a) unanchored continuous U-wrap; (b) anchored continuous U-wrap with conventional FRP-embedded anchors at the ends; and (c) fully closed external FRP hoops made of discrete FRP U-wrap strips and FRP through-anchors that penetrate the top slab and connect both ends of the FRP strips, combined with intermediate crack-control joints. The strengthening concept with FRP hoops precluded the premature debonding and anchor pullout issues of the two more conventional retrofit solutions and, despite a more challenging and labor-intensive installation, was selected for the in-situ implementation. The proposed hooplike EB-FRP shear-strengthening scheme enabled the deficient MRF beams to overcome a 30% shear overstress at the end-yielding region and to develop high-end rotations (e.g., 0.034 rad [3.4% drift] at peak and 0.038 rad [3.8% drift]) at strength loss for a beam that, otherwise, would have prematurely failed in shear. These values are about 30% larger than the ASCE 41 prescriptive value for the Life Safety (LS) performance objective. Energy dissipation achieved with the fully closed scheme was 108% higher than that of the unanchored FRP U-wrap and 45% higher than that of the FRP U-wrap with traditional embedded anchors. The intermediate saw-cut grooves successfully attracted crack formation between the strips and away from the FRP reinforcement, which contributed to not having any discernable debonding of the strips up to 3% drift. This paper presents the experimental evaluation of the three large-scale laboratory specimens that were used as the design basis for the final retrofit solution. [ABSTRACT FROM AUTHOR]

Soft soil sites can amplify the peak acceleration by a factor of 1.5 to 3.5 and exhibit the filtering effect on seismic waves. This effect results in the attenuation of high frequencies, amplification of low frequencies, and extension of the predominant period of ground motion. Consequently, soft soil sites have a more pronounced impact on isolation buildings constructed on them. The seismic isolation structure design typically involves assuming rigid foundation for calculations. However, the soil properties can significantly impact the dynamic response of the structure, affecting factors such as input ground motion, changes in vibration characteristics, radiation energy dissipation, and material damping energy dissipation. Therefore, neglecting these influences and relying solely on the rigid foundation assumption for calculations can lead to significant errors in the final seismic response analysis of the structure. Currently, there are numerous LNG storage tanks, museums, and other isolation buildings constructed on soft soil sites. Therefore, research on seismic isolation measures for soft soil sites holds significant practical importance. In light of this, this paper, firstly, provides a systematic summary of seismic isolation strategies and engineering applications for soft soil sites. Secondly, it further discusses advancements in research on the dynamic interactions of soil–isolated structures, covering analytical methods, numerical investigations, and experimental studies on soft soil sites. Lastly, the paper concludes with insights on current research progress and prospects for further studies. [ABSTRACT FROM AUTHOR]

As the use of electrochemical batteries, especially lithium–ion (Li-Ion) batteries, increases due to emerging applications and expanding markets, the accurate and fast estimation of their state of health (SOH) is becoming increasingly important. The accuracy of the SOH estimation is highly dependent on the correlation strength between the used indicator and SOH and the accuracy of the SOH indicator measurement. This paper presents a new differential indicator which has a strong and consistent correlation with the SOH of Li-Ion batteries, based on a new Electrochemical Impedance Spectrum (EIS) Phase–Magnitude relationship. It is shown in this paper that the EIS Phase–Magnitude relationship exhibits a phase-based differential impedance magnitude SOH indicator between a first-phase peak point and a last-phase valley point. Because of the differential nature of this SOH indicator and because the two impedance values are measured at a phase peak point and a valley phase point regardless of the phase absolute values, the effect of impedance measurement shift/offset (error) on SOH estimation is reduced. This supports the future development of more accurate and faster online and offline SOH estimation algorithms and systems that have a higher immunity to impedance measurement shift/offset (error). Furthermore, in this work, the EIS was measured for a lithium–ion battery that was down to a ~15% SOH, which was not only used to support the conclusions of this paper, but also helped in filling a gap in the literature for EIS data under deep/high degradation levels. [ABSTRACT FROM AUTHOR]

Currently, the energy dissipation efficiency of intermediate column dampers is extremely low, and traditional lever amplification damping systems occupy a large space in buildings. Aiming at solving these problems, this paper puts forward a new intermediate column–lever negative stiffness viscous damper (CLNVD), which has the characteristics of small impact on building space and significant amplification of the damper displacement. The CLNVD consists of the following four parts: the viscous damper, the negative stiffness device, the lever, and the intermediate column. This paper introduces the displacement amplification coefficient (fd) to assess the CLNVD's displacement amplification effect and introduces the energy dissipation coefficient (fE) to assess the CLNVD's energy dissipation effect. The expressions for fd and fE are derived according to the geometric magnification coefficient and effective displacement factor. Moreover, the impacts of multiple factors including the CLNVD's position, the lever's amplification coefficient, the bending line stiffness of beam, the negative stiffness, the damping coefficient, the damping index, and the inter-story displacement on the CLNVD's fd and fE are elaborated. The analysis results reveal the following: when the CLNVD is located in the middle of the span, the fd and fE of the CLNVD will be maximized, and fE will increase first and then decrease as the beam's bending line stiffness increases. Meanwhile, the amplification capability of the CLNVD increases as the lever's amplification coefficient χ rises. When the negative stiffness does not exist, there exists an optimum lever's amplification coefficient χ that maximizes fE. When the combination of damping coefficient c and index α satisfies a specific relationship, fE of the CLNVD reaches its largest value. When the negative stiffness and the loss stiffness of VD are within the region proposed in this paper, the CLNVD will achieve a higher fd and avoid providing significant negative stiffness. Subsequently, this paper proposes an optimization design method of the CLNVD. Finally, the amplification effect of CLNVD as well as the effectiveness of its optimization design method are verified through examples. In the case study, the CLNVD offers a larger damping ratio under the circumstance of fortification earthquakes. Under fortification and rare earthquakes, the inter-story displacement of Scheme 1 has been decreased by half roughly. According to the above-mentioned results, the CLNVD provides a brand-new approach for designers in the seismic design of buildings. Furthermore, this paper will provide beneficial reference for the damping design of other amplification devices equipped with negative stiffness dampers. [ABSTRACT FROM AUTHOR]

It is of paramount importance to ensure the safe operation of energy pipelines for pipeline owners and operators. Therefore, effective condition assessment of pipelines is imperative. For this purpose, there are a great number of models developed using various techniques. How to select a modeling approach and associated techniques to get the most of the effectiveness of the model under a condition with limited monitoring data and experience remains a big concern to pipeline operators. This paper provides a comprehensive review of the developed approaches and techniques for energy pipeline degradation condition assessment. The primary motivation behind this review is the pivotal role of condition assessment in energy pipeline integrity management and the proliferation of models and techniques, including statistical modeling, stochastic processes, machine learning, and deep learning, used for assessing pipeline degradation. This work aims to identify and assess the challenges and gaps inherent in the utilization of these condition modeling approaches. By systematically analyzing the current state of research and practice, this review not only highlights the strengths and limitations of various modeling approaches but also offers insights into future opportunities for enhancing the research and management practice in the field of pipeline integrity management. Our analysis offers valuable insights for researchers, practitioners, and policymakers in the domain of pipeline integrity management. It facilitates a better understanding of the complexities and intricacies of condition assessment, ultimately contributing to the development of more robust and effective strategies for safeguarding the integrity of energy pipelines. [ABSTRACT FROM AUTHOR]

Some challenges when implementing the optimized link state routing (OLSR) protocol on real-life devices and simulators are unmanageable: link quality, rapid energy depletion, and high processor loads. The causes of these challenges are link state processing, unsuitable multipoint relay (MPR) nodes, and information base maintenance. This paper proposes a structured, energy-efficient link sensing and database maintenance technique. The improved OLSR in the paper replaces the OLSRv2's HELLO, HELLO, and Topology Control (TC) message sequence with a new sequence. MPR nodes are not mandated to broadcast TC messages if the number of nodes and their OLSRv2 addresses remain unchanged after subsequent broadcasts or if no node reported 2-hop symmetric connections. The paper further proposes an MPR selection technique that considers four parameters: node battery level, mobility speed, node degree, and connection to the base station for optimum relay selection. It combines the four parameters into one metric to reduce energy dissipation and control routing overhead. The modifications were implemented in NS-3, and the simulation results show that our improved OLSR outperforms the existing OLSR, OLSRv2 and other improved routing protocols in energy consumption, routing overhead, the packet delivery ratio and end-to-end delay, as compared to the related literature. [ABSTRACT FROM AUTHOR]

The article highlights the research study related to the analysis of electroluminescence in powder devices with a paper substrate and inclusion of a receptive layer. Topics include the process of electroluminescence (EL) in powder EL devices; the mechanism by which light emission is enhanced was probed by measurements of the frequency dependence of the current, luminance and loss tangent.

With the development of modern fluid machinery, the energy density of pumps is gradually being improved, and at the same time, higher demands are being placed on the cavitation performance, hence the introduction of the inducer and centrifugal impeller to form a dynamic–dynamic series structure. However, there are strict constraints on the axial size of pumps in fields such as firefighting and aerospace. The traditional empirical formula no longer satisfies the need to fit the axial dimensions between the induced wheel and the impeller at high velocities. Therefore, based on the wave-piercing theory, the drag reduction coefficient is introduced to explore the optimal axial fit size from the perspective of energy characteristics. This paper focuses on the influence of the inducer's wake on the energy characteristics of downstream impellers, and conducts the following research: by adjusting the axial matching dimensions between the upstream inducer and the centrifugal impeller in the initial model, ten sets of axial distance models with matching dimensions of KD are designed, and the drag reduction coefficient is embedded to determine the optimal axial distance. The results show that the optimal axial distance is 0.2D, which is far lower than the axial distance value of 0.42D obtained from the traditional empirical formula for axial matching dimensions. Meanwhile, this paper uses tangential velocity, the inlet flow angle of the impeller, entropy production theory, and other indicators to analyze the internal energy loss of the high-speed vehicular fire pumps one by one. All of them confirm that the impeller in the high-speed vehicular fire pump has the lowest energy loss and optimal performance at an axial distance of 0.2D. Specifically, at this axial distance, the head can reach 259 m, and the hydraulic efficiency is as high as 83.62%. Thus, the feasibility of determining the axial placement of the impeller using the drag coefficient is validated. This research provides new insights into determining the axial coordination dimensions between the inducer and the impeller. [ABSTRACT FROM AUTHOR]

With the development of smart grids and new power systems, the combination of non-intrusive load identification technology and smart home technology can provide users with the operating conditions of home appliances and equipment, thus reducing home energy loss and improving users' ability to demand a response. This paper proposes a non-intrusive load decomposition model with a parallel multiscale attention mechanism (PMAM). The model can extract both local and global feature information and fuse it through a parallel multiscale network. This improves the attention mechanism's ability to capture feature information over long time periods. To validate the model's decomposition ability, we combined the PMAM model with four benchmark models: the Long Short-Term Memory (LSTM) recurrent neural network model, the Time Pooling-based Load Disaggregation Model (TPNILM), the Extreme Learning Machine (ELM), and the Load Disaggregation Model without Parallel Multi-scalar Attention Mechanisms (UNPMAM). The model was trained on the publicly available UK-DALE dataset and tested. The models' test results were quantitatively evaluated using a confusion matrix. This involved calculating the F1 score of the load decomposition. A higher F1 score indicates better model decomposition performance. The results indicate that the PMAM model proposed in this paper maintains an F1 score above 0.9 for the decomposition of three types of electrical equipment under the same household user, which is 3% higher than that of the other benchmark models on average. In the cross-household test, the PMAM also demonstrated a better decomposition ability, with the F1 score maintained above 0.85, and the mean absolute error (MAE) decreased by 5.3% on average compared with that of the UNPMAM. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) are mostly used for monitoring the environment; however, they are usually powered by non-rechargeable batteries with limited energy. Solar energy harvesting is an attractive solution to the limit by charging the sensor nodes; however, the harvested solar energy is easily affected by weather conditions. Based on the characteristics of uncertainty and intermittency of solar energy, this paper proposes a plus-profile solar energy prediction algorithm. This algorithm makes the prediction of future available solar energy by finding the data in the dataset that is most similar to the data of the day and combining it with recent weather trend. According to the predicted result, the paper further proposes an adaptive energy management scheme to suit the harvested energy. In the scheme, sensor nodes can adaptively adjust task scheduling to achieve energy neutrality. The simulation results show that compared with other algorithms, the prediction accuracy of the proposed prediction algorithm is improved by 17.7 and 22.4%, respectively, and the proposed energy management scheme reduced energy loss by 6.2 and 46.8%, respectively. [ABSTRACT FROM AUTHOR]

The Fibre reinforced concrete (FRC) has become popular in construction industry in last few decades. Various natural and artificial fibres are added in concrete to enhance the crack resistance property by developing some bonding between fibre and concrete. FRC is not only performs better than conventional concrete but also the fibre reinforced concrete (FRC) has become popular in construction industry in last few decades. FRC is not only performs better than conventional concrete but also it reduces environmental pollution. Actually in many rural area, people are not concerned about the pollution and hygiene. The unused portion of sugarcane fibre, banana fibre, jute fibre are thrown into pond/ lake. After few days they decompose and rotten, that causes pollution in waterbody and disturb the ecosystem. The fibres can be used as additive in concrete to enhance their overall performance as well as to reduce environmental pollution. In this paper, a state-of-art review has been investigated on FRC and its different benefits. Different fibres such as jute fibre, coconut fibre, polypropylene, basalt, areca leaf, glass, mask, plastic, carbon and steel fibre were incorporated in concrete by several researchers in the past decades that have been highlighted in detail in this paper. The performance has been evaluated in terms of load displacement hysteretic pattern, stiffness, ductility, energy dissipation, crack resistance, durability and workability of FRC. The virtue and limitations of FRC have also been discussed. From the existing literature, it is found that the performance of FRC under dynamic load, Damage assessment, Time dependent assessment of damage, Effect of fibre in high-performance concrete (HPFRC) and Life cycle assessment are found as major literature gap that needs to be fulfilled. A case study on damage assessment of FRC has also been conducted in this paper. From the result it is found that the Carbon fibre reinforced concrete (CFRC), Steel fibre reinforced concrete (SFRC) and Areca leaf sheath fibre reinforced concrete (ALSFRC) are experiencing lesser damage in compared to normal concrete without fibre. Based on the existing literature the future scope and probable direction of research of FRC have also been highlighted. [ABSTRACT FROM AUTHOR]

Backgrounds: In this paper, a kind of mining MR damper with shear and valve working mode is designed. Compared with the traditional damper, this MR damper has better energy dissipation characteristics and can provide greater damping force in a short time. Its damping can be adjusted with the excitation current. Purposes: The aim of the present paper is to analyze and study the performance of this novel mining MR damper and test the working performance and feasibility of this MR damper. Methods: Optimizing and establishing a Simulink dynamic simulation model based on Bingham model and testing the performance parameters of the MR damper. The vibration mitigation experiment of mining vibrating screen based on spring damper is designed. Results: This paper compares the experimental and simulation results and found that the error of the maximum damping force shall not exceed 3%.Compared with traditional metal spring and ROSTA spring, the MR damper can reduce the downtime of the vibrating screen by more than 80%. Conclusions: From the results, the present paper provides theoretical basis for the performance test of the damper. The excitation current is the main factor affecting the maximum damping force of the MR damper. The correlation between the excitation current and the maximum damping force is more than 90%. MR damper can not only effectively avoid the resonance of the vibrating screen, but also will not affect the stable amplitude of the vibrating screen when it works, and can also greatly reduce the downtime of the vibrating screen. [ABSTRACT FROM AUTHOR]

In order to solve the problem of the lack of maneuverability of the conventional underwater glider, this paper proposes a hybrid-driven underwater glider equipped with a Kappel tip rake propeller, analyzes the propulsion performance of different types of Kappel tip rake propellers in the wake field of the hybrid-driven underwater glider, optimizes the overall propulsion performance of the hybrid-driven underwater glider, and realizes self-propulsion and gliding with high efficiency and low energy consumption. In the research process, the Schnerr–Sauer cavitation model and the cavitation simulation strategy of VOF two-phase flow were adopted, coupled with the SST k-ω and γ transition turbulence model, and the control calculation error was not more than 3%. Based on the hydrodynamic performance study of the Kappel tip rake propeller, the self-propelled simulation was carried out under the working conditions of 6 kn, 5 kn, 4 kn, and 3 kn, and the gliding simulation was carried out under the working conditions of 1 kn, 0.5 kn, and a glide angle of 12°. The propulsion performance of the hybrid-driven underwater glider with different models of Kappel tip rake propellers was analyzed. It was found that the maximum open water propulsion efficiency of the propeller Kap05 had the largest improvement, which was 3.07% higher than that of the reference base propeller. Under the self-propelled condition, the hybrid-driven underwater glider with the propeller Kap05 had the lowest wake fraction, and the propellers Kap04 and Kap05 had the best propulsion performance in the wake field of the hybrid-driven underwater glider. In the gliding condition, the form of the folding paddle can reduce the gliding resistance generated by the propeller by more than 45% and the gliding negative lift by more than 68%. A moderate tip rake can effectively improve the propulsion efficiency of the Kappel tip rake propeller in the wake field of the hybrid-driven underwater glider, reduce energy loss, and improve the overall performance of the hybrid-driven underwater glider. [ABSTRACT FROM AUTHOR]

This paper reviews sintered silver (s-Ag) die-attach materials for wide band gap (WBG) semiconductor packaging. WBG devices that die-attach with s-Ag have attracted a lot of attention owing to their low energy loss and high temperature operation capabilities. For their practical operation, a reliability design should be established based on the failure of physics of the s-Ag die layer. This paper first focuses on the material characteristics of the s-Ag and tensile mechanical properties. Then, the s-Ag die-attach reliability is assessed with high-temperature storage, power cycling, and thermal shock tests. Each fracture mode was discussed by considering both the fracture surface analysis results and its mechanical properties. Finally, the effective reliability design parameters of the s-Ag die layer are introduced. [ABSTRACT FROM AUTHOR]

Recently, a new type of lighting source, deep ultraviolet light-emitting diode (LED), has appeared in the markets of space purification and surface sterilization. In this paper, a new type of electronic lighting driver for supplying a deep-ultraviolet LED sterilization lamp is proposed and developed. The main circuit combines a buck converter and a flyback converter into a single-stage single-switch buck-flyback AC-DC power converter with power factor correction. In addition, the proposed electronic lighting driver leverages a wide bandgap SiC Schottky diode as the output diode to lower the power diode losses and recycles the energy stored in the leakage inductance of the transformer in order to improve the circuit efficiency. The magnetizing inductor inside the presented AC-DC power converter is designed to operate in discontinuous conduction mode (DCM), which naturally enables power factor correction (PFC). A single-stage prototype driver with a power rating of 3.6 W (90 V/40 mA) was developed and implemented for providing a deep ultraviolet LED disinfection and sterilization lamp. Experimental results show that the measured power factor (PF) is greater than 0.9 and the measured total harmonic distortion (THD) of the input current is less than 18% at an input utility voltage of 110 V. Furthermore, the measured output voltage ripple factor is less than 1% and the output current ripple factor is less than 4%. In addition, the proposed single-stage electronic lighting driver for supplying a deep ultraviolet LED disinfection and sterilization lamp achieves high circuit efficiency (greater than 90%), low circuit component count, and low circuit cost. [ABSTRACT FROM AUTHOR]

Bolted joints play a more and more important role in the structure with lighter weight and heavier load. This paper aims to provide an overview of different experimental approaches for the dynamic behavior of structures in the presence of bolted joints, especially the energy dissipation or damping at frictional interfaces. The comprehension of energy dissipation mechanisms due to friction is provided first, while the key parameters and the measurement techniques, such as the excitation force, the preload of the bolt, or the pressure at the interfaces, are briefly introduced. Secondly, the round-robin systems aim to measure the hysteresis parameters of the frictional joints under tangential loads are reviewed, summarizing the basic theory and the strategies to apply the excitation force or acquire the response in different testing systems. Followed by parameter identification strategies for bolted structures, the test rigs with one or more simplified bolted joints are summarized to give an insight into the understanding of typical characteristics of bolted structures, which are affected by the presence of friction. More complex test rigs hosting real-like or actual engineering structures with bolted lap or flange joints are also introduced to show the identification process of the dynamic characteristics of bolted connections employed in specific applications. Based on the review paper, researchers can get the basic knowledge about the experimental systems of the bolted structures, especially several classical round robin systems, such as the Gaul resonator and widely used Brake-Reuß beam system. Readers can take advantage of this background for more creative and effective future studies, make more progress on the study of assembled structures and understand the influence of bolting frictional connections on the dynamic response better. [ABSTRACT FROM AUTHOR]

In the field of handling, storage and transportation, chutes are used to transfer bulk solids between conveyors and warehouses. In these systems, traditional analytical methods based on the principles of continuum mechanics approximate an accelerated flow that contains the physical body solid properties obtained from standardized tests. Because it is difficult to physically observe the flow inside the transfer structure, there have been few studies to validate the method at full scale. In contrast, discrete element modeling (DEM) allows flow visualization through a transfer chute and qualitative and quantitative analysis if accurate simulation parameters are selected. In order to adapt to the needs of modern intelligent warehousing, we reduced the grain crushing and damage in the process of grain storage. To design and investigate the motion performance of grain particles in a sliding dustpan, this paper utilizes rocky simulation technology, combined with the corresponding bench experiments, to study the impact of the angle arrangement of the dustpan, and to verify the results of the simulation analysis based on the stress–strain analysis of the particle impact. It was found that when the angle of the dustpan arrangement was 40 degrees, the flow of all particles had a better performance in terms of pass ability and energy loss. In the continuous cycle obtained from the simulation, the particle group state at each moment is almost the same as the particle characteristics in the experiment, indicating that the angle of the bucket has an effect on the particle permeability. In this paper, the results of the study on the state of the grain group on the silo device will provide a useful reference for the design of a grain silo device. [ABSTRACT FROM AUTHOR]

Energy saving is an important measure to promote social green transformation. The traditional energy-saving ideas usually only focus on a specific loss, and seldom consider the possible relationship and influence among various losses. In relatively complex energy-using systems, there are often many kinds of losses, and each loss may have many influencing factors. There may be some relationship between these losses and the influencing factors. To solve this problem, this paper presents an analysis method of the variable association in multi-variable systems. First, the basic relationships between variables and the representation methods are discussed. The basic concept of a path between variables is given, and the analysis method of variable association based on path statistics is provided. This paper focuses on the analysis of the influencing factors and paths of the observed variables, as well as which observed variables will be affected by a control variable. Then, based on the correlation matrix, the quantitative analysis method of the influence between variables is given. Variable correlation analysis is innovatively applied in the field of energy saving to determine the correlation of losses through variable associations, guiding the preliminary screening of energy-saving measures and analyzing the collateral effects of these measures. Based on the correlations between energy losses, a scientific process for formulating energy-saving measures is proposed. The variable correlation analysis method proposed in this paper is a generalized method, which can judge the correlation between variables from the perspective of theoretical analysis and avoid the dependence on data. In addition to good applications in the field of energy conservation, it can also be widely used in construction, transportation, climate change, and other fields. The proposed energy-saving ideas take into account the intensity of influencing factors on loss and the correlation between loss, which improves the effectiveness of energy saving measures. [ABSTRACT FROM AUTHOR]

This research paper introduces an optimization methodology for the strategic electric sources' placement at multiple positions in a DC islanded microgrid characterized by a mesh network, aiming to minimize line losses while considering minimal cable weight. The DC microgrid studied in this paper is composed of PV panels, batteries, a diesel generator, and 20 residential loads. Employing Dijkstra's algorithm, a graph algorithm used in Google Maps, the study identifies the shortest path (resistance) between potential source nodes and various variable loads within a predefined electric distribution mesh network topology. This study focuses on active power considerations and offers valuable insights into the placement optimization of multiple sources' positions in DC microgrid mesh networks. A key contribution of this paper lies in the ranking of source node positions based on minimal to maximal line losses, taking into consideration optimal cable weights, while using MATPOWER to validate sources' ranking based on Dijkstra's hypothesis. The research further includes a techno-economic study to assess the viability of sources' placement at multiple positions within the mesh network, comparing it with the optimal placement scenario involving a single position for all sources. This methodology serves as a valuable resource for system designers and operators aiming to minimize line losses and optimize energy distribution in DC microgrids in a mesh topology. [ABSTRACT FROM AUTHOR]

In Europe, it is estimated that 14% of existing buildings were built before 1919, whereas 26% were built before 1945. In Romania, about 31% of the buildings date from before 1961, contributing to the current stock of old buildings with historic and architectural value in the country. This paper illustrates the current state of buildings with historic and architectural value in Romania, alongside a case study of a representative administrative building in Câmpulung, Romania. The analysis of the Town Hall building in Câmpulung, Romania, demonstrates that potential energy savings of up to 47.53% can be achieved by implementing interventions such as upgrading windows, insulating the attic, and installing photovoltaic panels. The highest energy reduction is obtained by replacing the window glass with a value of 18.16% with attic insulation with a value of 16.1%. This paper also presents indoor measurements of temperature and humidity in different offices positioned in the north and the south. The study conducted on the south façade office revealed consistent temperatures ranging from 21.7 °C to 24.4 °C, with an average of 23.31 °C. However, the humidity levels fluctuated considerably, ranging from 17.1% to 39.1%, with an average of 26.89%. The sun-exposed section of the building saw relatively stable temperature conditions, but the varying humidity levels could have a detrimental impact on the quality of the indoor atmosphere and potentially decrease the effectiveness of the workforce. By contrast, the north façade office exhibited lower and more fluctuating temperatures, ranging from 19.8 °C to 23.6 °C, with an average of 21.74 °C. Additionally, it had higher and more stable humidity levels, ranging between 19.5% and 41.7%, with an average of 29.83%. A thermographic analysis was performed on the north façade of the Câmpulung Town Hall, utilizing thermal imaging technology to detect areas of heat loss, and thus identifying the energy inefficiency problems of the building's exterior. The investigation found notable variations in temperature, especially around the windows, where temperatures could be as high as 14.1 °C, highlighting the insufficiency of the building's antiquated timber-framed windows in preventing energy loss. [ABSTRACT FROM AUTHOR]

Once there is a velocity gradient in a viscous fluid-flow, such as that across a shock wave, a viscous force and viscous energy loss exist inside the flow according to the Navier-Stokes equation, which may confuse the relative contribution of compressibility and viscosity. In this paper, a viscous shear vector is defined as the component of gradient vector of local velocity magnitude perpendicular to the velocity vector. Then, a local viscous energy flux vector is defined from the viscous shear vector after being multiplied by the viscosity and the velocity magnitude. The divergence of the viscous energy flux vector results in new expressions for viscous force and loss of viscous energy, in which all the square terms of derivative of velocity components correspond to irreversible energy loss. The rest part can be taken as a kind of mechanical energy transfer done by the viscous force, from which the viscous force components can be got based on the assumption that the viscous force vector is parallel to the velocity vector. The new equations are different from and more complex than those in the traditional Navier-Stokes equation. By the new theory, it is shown that there is no shear viscous force and shear viscous energy loss in the flow across a normal shock wave without velocity gradient perpendicular to the flow direction. [ABSTRACT FROM AUTHOR]

Due to its simplicity, the one-diode model is commonly used for modeling the operation of photovoltaic (PV) modules at standard test conditions (STC). However, its inherent implicit nature often presents challenges in modeling PV energy production. In this paper, the innovative explicit one-diode model developed by us over time is adapted for estimating PV power production under real weather conditions. Simple yet accurate equations for calculating the energy output of a PV generator equipped with a maximum power point tracking (MPPT) system are proposed. The model's performance is assessed under various normal and harsh operating conditions against measured data collected from the experimental setup located at the Solar Platform at West University of Timisoara, Romania. As an application of the new equation for maximum power, this paper presents a case study where the energy loss in the absence of an MPPT system is evaluated based on atmospheric and sky conditions. [ABSTRACT FROM AUTHOR]

This research paper explores the intricate connections between dematerialization, the expanded field, and expanded cinema, drawing insights from cybernetics and trans-aesthetics. Its objective is to investigate the thematic and aesthetic concerns embedded within these concepts and their manifestation in Michelangelo Antonioni's trilogy: Blow-Up (1966), Zabriskie Point (1970), and The Passengers (1975). The study examines Antonioni's inquisition of reality, perception, and play-with images within the expanded field and his politics of dematerialization. The investigation delves into the profligacy and fragmentation of traditional material forms into abstract, conceptual realms, known as dematerialization, which aligns with the expanded field's expansion of artistic expressions and media. Drawing upon cybernetics and maneuvering within queer computational history, the research establishes a theoretical framework for understanding the interconnectedness of these concepts and, furthermore, explores the configuration of autopoiesis and its interplay between systems and environment. The paper attempts to illustrate the impact of universal brain inception, Total AI, and expanded cinema. Moving forward, this study strives to emphasize the structure of the trans-individual, who transcends the consternation of obliteration. So essentially, there's an expansion of consciousness in the realm of expanded reality. The paper is divided into 4 sections that move from one part to another through a comprehensive analysis of Antonioni's Post-World War II films via their obstreperous electronic and abstraction aesthetics, identifying underlying motifs, aesthetic choices, and narrative techniques encrypted in these motion pictures that lie more and more beyond their surface reality. It explores how Antonioni's images embody the dematerialization of history-signs-counterculture-computational networks. Additionally, the murdering of space and expansion rhetoric is methodically disseminated through visual and subtextual symbolism. The research paper takes on a network-driven approach in its investigation, connecting these concepts to unravel their significance in cinema and their metamorphosis since the reverberated effect of the mushroom cloud, its maleficent dematerialization of humanity in Hiroshima. It sheds light on the transformative impact of technology on cinematic expression, the enfolding of temporal structures, the evolution of artistic possibilities, and the blurring of boundaries between art forms. The basal hypothesis of entropy, the second law of thermodynamics predicting energy dissipation and organizational dissolution, serves as a connecting thread. It underscores the transient and ephemeral nature of artistic expressions within the expanded field, expanded cinema, and dematerialization, all moving towards surging entropy. [ABSTRACT FROM AUTHOR]

The dynamic response and operational reliability of high-speed solenoid valve (HSV) for diesel engine injector are the main indicators to measure their performance. At high-frequency, the eddy current energy and Joule energy generated by the HSV will be converted into heat, which has a significant impact on the service life of HSV. The optimization of HSV involves the interaction between energy loss and the dynamic response of HSV. To optimize the HSV dynamic response time considering energy loss, the HSV work process simulation model was established in this paper, and the model was verified based on armature lift experimental data. Without changing the structural parameters of the HSV, the four parameters of electroconductibility, spring stiffness, damping coefficient, and coil resistance were selected as the key parameters affecting the dynamic response and energy loss. The response surface models (RSMs) of opening response time, closing response time, eddy current energy and Joule energy of the HSV were constructed by using the smoothing spline-analysis of variance method. The multi-objective cooperation optimization of HSV under the interaction of dynamic response characteristics and energy loss was completed by using non-dominated sorting genetic algorithms. After optimization, the opening and closing response times of HSV were reduced by 15.1% and 16.6% respectively, while the eddy current energy and Joule energy were reduced by 5.2% and 48.4% respectively. In this paper, the dynamic response and energy loss were jointly optimized. The presented results provide theory instruction for multi-objective cooperative optimization of HSV. [ABSTRACT FROM AUTHOR]

A novel dual-plane dye laser PIV technique used to analyze helicity and energy dissipation in an unexcited turbulent swirling jet of pressurized cold air has established that regions within the flow field of the jet exhibiting high helicity are correlated with regions of high turbulent kinetic energy dissipation. This PIV configuration provides estimates of all components of the velocity gradient tensor, facilitating calculation of the helicity from the vorticity components. Application of this novel dual-plane PIV technique is extended in this study to investigate helical structures in a turbulent swirling jet where the underlying shear flow is subjected to external acoustic sinusoidal forcing in a plane perpendicular to the central axis of the jet. It was found that acoustic excitation had a significant effect on the mean velocity profile parallel to the direction of the jet. The horizontal forcing resulted in the generation of vorticity that was skewed with a pitch that favored a distribution of angles around 90° with respect to the velocity vector. The distribution of the time-averaged helicity angle indicated organized helical activity, but such activity is not dominated by large-scale coherent structures of maximal helicity. [ABSTRACT FROM AUTHOR]

Recently, we published two papers in this journal. One of the papers dealt with the action of the radiation fields generated by a traveling-wave element and the other dealt with the momentum transferred by the same radiation fields and their connection to the time energy uncertainty principle. The traveling-wave element is defined as a conductor through which a current pulse propagates with the speed of light in free space from one end of the conductor to the other without attenuation. The goal of this letter is to combine the information provided in these two papers together and make conclusive statements concerning the connection between the energy dissipated by the radiation fields, the time energy uncertainty principle and the elementary charge. As we will show here, the results presented in these two papers, when combined together, show that the time energy uncertainty principle can be applied to the classical radiation emitted by a traveling-wave element and it results in the prediction that the smallest charge associated with the current that can be detected using radiated energy as a vehicle is on the order of the elementary charge. Based on the results, an expression for the fine structure constant is obtained. This is the first time that an order of magnitude estimation of the elementary charge based on electromagnetic radiation fields is obtained. Even though the results obtained in this paper have to be considered as order of magnitude estimations, a strict interpretation of the derived equations shows that the fine structure constant or the elementary charge may change as the size or the age of the universe increases. [ABSTRACT FROM AUTHOR]

Using a two-dimensional empirical sea wave spectral model at full development, this paper performs an assessment of the compatibility of the energy and momentum budgets of sea waves over the whole spectral range. Among the various combinations f model functions for wave breaking and wind source terms tested, no one fulfilled simultaneously the energy and momentum balance of the transfer equation. Based on experimental and theoretical grounds, wave breaking is known to contribute to frequency downshift of a narrow-banded wave spectrum, when the modulational instability is combined with wave breaking. On those grounds, it is assumed that, in addition to dissipation, wave breaking produces a spectral energy flux directed toward low wavenumbers. I show that it is then possible to remove the energy and momentum budget inconsistency, and correlatively the required strength of this spectral flux is estimated. Assuming such a downward spectral flux permits to fulfill both energy and momentum balance conditions, while slightly reducing the consistency between source terms and empirical spectra, as estimated by a cost function K. Other tests were performed in which it was further assumed that wave breaking would also be associated with azimuthal diffusion of the spectral energy. This could allow a slight improvement of the cost function K, and might correlatively reduce the required downward spectral flux by a factor of 4, although it would not be able to remove it entirely. [ABSTRACT FROM AUTHOR]

Aiming at the problem of excessive vertical vibration caused by seismic primary waves in jacket structures located in seismic zones in China, a new type of shear plate metal damper with upper and lower elliptical openings (SPA) is proposed in this paper. The seismic model test is carried out to compare the shear plate metal damper with three traditional opening forms, central elliptical opening, single row opening, and double row opening, and the hysteretic curve, skeleton curve, and cyclic hysteretic energy dissipation capacity are analyzed. The results show that the energy dissipation performance of the new shear plate metal damper with upper and lower elliptical openings proposed in this paper is better than that of the other three types of dampers. [ABSTRACT FROM AUTHOR]

In the process of logistics, shock and vibration are the most important factors contributing to product damage. Assembling honeycomb paperboard and EPE is commonly used to provide cushioning and anti-vibration effects to materials. Therefore, it is necessary to study the vibration transmission properties of this kind of assembly in the anti-vibration process. The aim of this paper was to experimentally determine the vibration transmission properties of assemblies with honeycomb paperboard and expanded polyethylene (EPE). Through a sinusoidal sweep vibration test of this assembly, the vibration transmission characteristic curves of assemblies with honeycomb paperboard and EPE of different thicknesses were obtained and compared. Assuming the assembly and mass block as a single degree of freedom with a small damping linear system, the damping energy dissipation of the assembly and the resonance frequency were obtained. The vibration transmission property curves of the assembly can be divided into four regions. With an excitation acceleration of 0.5 g and a honeycomb paperboard with a thickness of 60 mm (F60), the vibration transmission rate and the resonance frequency—of the material dampened with EPE at a thickness of 60 mm (E60), and the assembly (F30/E30) with a 30 mm thick honeycomb paperboard and 30 mm thick EPE—increased by −2.5% and −17.5%, −86.9% and 79.3%, and −95.9% and −85.7%, respectively. Compared to the assembly with 20 mm thick honeycomb and 20 mm thick EPE (F20/E20), the vibration transmission rate, the resonance frequency, and the material damping and damping energy dissipation of F40/E20, F30/E30, and F20/E40 increased by 75.6%, 48.3%, and 66.1%; 1.2%, −21.5%, and −38.9%; 241.5%, 82.8%, and 13.3%; and 12.5%, 98.9%, and 106.8%, respectively. Compared to F60 and E60, the damping energy dissipation of F30/E30 increased by 2816.7% and 133.3%, respectively. The assembly of F30/E30 has the smallest vibration transmission rate and the most vibration energy dissipation among these assemblies. This means that the assembly of F30/E30 absorbs the most external vibration energy, while the acceleration that is transmitted to the internal product is minimal. Therefore, in the design of cushioning packaging, according to the characteristics and natural frequency of the internal products, an appropriate assembly can be selected, which should have a lower vibration transmission rate and more vibration energy dissipation, and should not resonate with the internal product. This will provide a theoretical basis for the design of cushioning packaging. [ABSTRACT FROM AUTHOR]

Breaking internal waves play a primary role in maintaining the meridional overturning circulation. Oceanic lee waves are known to be a significant contributor to diapycnal mixing associated with internal wave dissipation, but direct measurement is diffcult with standard oceanographic sampling methods due to the limited spatial extent of standing lee waves. Here, we present an analysis of oceanic internal lee waves observed offshore eastern Costa Rica using seismic imaging and estimate the turbulent diffusivity via a new seismic slope spectrum method that extracts diffusivities directly from seismic images, using tracked reflections only to scale diffusivity values. The result provides estimates of turbulent diffusivities throughout the water column at scales of a few hundred meters laterally and 10m vertically. Synthetic tests demonstrate the method's ability to resolve turbulent structures and reproduce accurate diffusivities. A turbulence map of our seismic section in the western Caribbean shows elevated turbulent diffusivities near rough seafloor topography as well as in the mid-water column where observed lee wave propagation terminates. Mid-water column hotspots of turbulent diffusivity show levels five times higher than surrounding waters and fifty times greater than typical open-ocean diffusivities. This site has steady currents that make it an exceptionally accessible laboratory for the study of lee-wave generation, propagation and decay. [ABSTRACT FROM AUTHOR]

The dynamic response of dielectric elastomers is widely used in many functional devices, but current research has neglected the effect of varying dielectric permittivity on their dynamic oscillations and stability. This paper studies the thin-walled dielectric balloon in which the stretch-dependent dielectric permittivity is considered. We obtain the dynamic equation of motion by Hamilton's principle. Based on the principle of no energy dissipation in conservative systems, we establish energy conservation at the maximum stretching position and at the initial moment, then we investigate the stability in the dynamic case. It is found that a stretch-related dielectric permittivity can increase the critical electric field of the balloon and can also change the mode of electric field instability and modulate the critical stretch value. In the dynamic case, the stretch-dependent permittivity increases the critical electric field by 4 % when the balloon is only subjected to electric force; moreover, it increases the critical stretch value by 316.68 % by changing the unstable mode from pull-in instability to snap-through instability. It is hoped that this work will provide new thinking in designing functional devices by using the dynamical response and stability of dielectric elastomers. [ABSTRACT FROM AUTHOR]

The work in this paper is applied to the Zhangbei Power grid. In the flexible direct current (DC) power system, the fault current rises extremely fast when a DC fault occurs. The requirements for the peak of breaking current and fault energy absorption of DC circuit breakers (DCCBs) increase linearly, which significantly increases the cost of the equipment. Therefore, in order to reduce the design difficulty of DCCBs, this paper proposes a strategy to control energy after the fault occurs. Firstly, the energy dimension is added on the basis of the traditional vector control of MMC, which constitutes a three-dimensional energy direct control. Subsequently, the architectures of energy fluctuation control and feedforward control are proposed. The influencing mechanisms for the peak fault current, peak fault voltage and energy dissipation are analyzed. Finally, the simulation of energy fluctuation control and feedforward control is constructed on PSCAD/EMTDC. The simulation results show that the energy fluctuation control is obviously better than the conventional three-dimensional energy control, and the feedforward energy control is further improved on this basis. Compared with the conventional vector control, the peak energy is reduced by 45.43% and the peak current is reduced by 25.39%, which helps to simplify the equipment design and reduce the equipment cost. [ABSTRACT FROM AUTHOR]

This paper presents an energy-saving and lifetime-maximizing solution for the LoRa wireless mesh network (WMN). Energy dissipation is a crucial factor affecting the usability of the LoRa WMN. In the worst cases, in systems without electric mains, the life of a sensor node battery may last for only a few hours. Two proposed solutions are characterized as energy-saving due to the use of deep sleep in the ESP8266-12F microcontroller. This allows the optimization of duty cycling, which refers to the ratio between active and inactive periods of sensor nodes power-gating the node, i.e. turning off all circuitries. This solution benefits applications using active power-hungry sensors sampled many times daily. Notably, reducing power consumption during idle time increases the optimal battery life by up to hundreds of times. As a result, the automatic uptime of a LoRa WMN can increase from days to months or even years, depending on usage. Therefore, energy-saving must be optimized if the node is to be installed in locations without a grid or renewable energy source. Experimental results show that the proposed energy-saving solution is more effective than those introduced by previous studies. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the criteria for selecting pleated filter partitions used in passenger car engine filters. The paper presents the problem of optimizing pleated air filters in the direction of minimizing pressure drop, which is the source of engine energy losses. Two criteria for selection of a paper filter partition for specific operating conditions of the filter and the engine are presented: criterion of permissible separation speed and criterion of permissible pressure drop. The actual filtration area of 44 paper pleated filter elements used in passenger cars and the air stream flowing through the filter were determined, which made it possible to calculate separation speed. In 62% of the analyzed filter inserts, the calculated separation speeds are within the speed range recommended by the constructors, uFmax = 0.06-0.12 m/s. Exceeding permissible separation speed uFmax = 0.12 m/s was found mainly in supercharged engines. Negative effects of engine operation with an air filter with too small separation area are presented, in the form of increased pressure drop and energy loss of the engine as well as shorter car mileage to reach permissible pressure drop. [ABSTRACT FROM AUTHOR]

Using the AC electric field to induce the orientation of nonlinear conductive fillers in composites is an effective solution for alleviating electric field distortion in power modules. However, the mechanism by which the electric field affects the filler dynamic characteristics and the composites' electrical properties remains unclear. In this paper, the correlation between the microscopic dynamic processes of fillers and the macroscopic current amplitude was analyzed. The results show that the current increases rapidly (0 ∼ 173 s) and then slowly (173 ∼ 869 s) at 600 V mm−1, influenced by the rotation and attraction processes of the fillers. This demonstrates that the orientation stops at about 869 s and the filler orientation state is a key factor in determining the dielectric properties. Secondly, the global orientation evaluation index D for the filler network was proposed, which can also derive the minimum time and energy loss required for preparation. Finally, the impact of different filler orientations on the composites' conductivity was investigated. In the low electric field stress region, with the average carrier jump distance decreasing from 150.23 to 109.71 nm as the D increases from −0.93 to −0.05. On this basis, materials with nonlinear conductivity gradient distribution can be easily prepared. Before optimization, the electric field stress of the power module at the triple point was 35.79 kV. This composite can reduce the value to 15.42 kV, a decrease of 56.9%, while maintaining good electric field uniformity. [ABSTRACT FROM AUTHOR]

The conservative Allen-Cahn equation satisfies three important physical properties, namely the mass conservation law, the energy dissipation law, and the maximum bound principle. However, very few numerical methods can preserve them at the same time. In this paper, we present a multi-physical structure-preserving method for the conservative Allen-Cahn equation with nonlocal constraint by combining the averaged vector field method in time and the central finite difference scheme in space, which can conserve all three properties simultaneously at the fully discrete level. We propose an efficient linear iteration algorithm to solve the presented nonlinear scheme and prove that the iteration satisfies the maximum bound principle and a contraction mapping property in the discrete L ∞ norm. Furthermore, concise error estimates in the maximum norm are established on non-uniform time meshes. The theoretical findings of the proposed scheme are verified by several benchmark examples, where an adaptive time-stepping strategy is employed. [ABSTRACT FROM AUTHOR]

Purpose: To find the quasi-static thermoelastic stress and displacement, the proposed model looks at how the microstructures interact with each other and how the temperature changes inside a rod. It uses the fractional-order dual-phase-lag (FODPL) theory to derive analytical solutions for one-dimensional problems in nonsimple media within the MDD framework. The dimensionless equations are used to analyze a finite rod experiencing the heat sources continuously distributed over a finite portion of the rod which vary with time according to the ramp-type function with other sectional heat supplies kept at zero temperature. The study introduces a technique using integral transforms for exact solutions in the Laplace transform domain for different kernel functions. Design/methodology/approach: A novel mathematical model incorporating dual-phase-lags, two-temperatures and Riesz space-fractional operators via memory-dependent derivatives has been established to analyze the effects of thermal stress and displacement in a finite rod. The model takes into account the continuous distribution of heat sources over a finite portion of the rod and their time variation according to the ramp-type function. It incorporates the finite Riesz fractional derivative in two-temperature thermoelasticity with dual-phase-lags via memory effect, and its solution is obtained using Laplace transform with respect to time and sine-Fourier transform with respect to spatial coordinates defined over finite domains. Findings: In memory-dependent derivatives, thermal field variables are strongly influenced by the phase-lag heat flux and temperature gradient. The non-Fourier effects of memory-dependent derivatives substantially impact the distribution and history of the thermal field response, and energy dissipation may result in a reduction in temperature without heat transfer. The temperature, displacement and stress profile exhibit a reduced magnitude with the MDD effect compared to when the memory effect is absent (without MDD). To advance future research, a new categorization system for materials based on memory-dependent derivative parameters, in accordance with the principles of two-temperature thermoelasticity theory, must be constructed. Research limitations/implications: The one-dimensional assumption introduces limitations. For example, local heating of a one-dimensional plate will not extend radially, and heating one side will not heat the surrounding sides. Furthermore, while estimating heat transfer, object shape limits may apply. Originality/value: This paper aims to revise the classical Fourier law of heat conduction and develop analytical solutions for one-dimensional problems using fractional-order dual-phase-lag (FODPL) theory in nonsimple media in the context of MDD. [ABSTRACT FROM AUTHOR]

This paper reports an experimental and analytical investigation on a novel self-centering damper. The damper is characterized by a multistage energy-dissipation mechanism, which is desirable for multiperformance-based seismic designs. The conceptual design, working mechanism, assembling process and hysteretic performance of the proposed damper are presented. The fundamental mechanical behavior of each component of the damper was examined experimentally. Then a series of cyclic tests of damper specimens was conducted, focusing on the influence of the preload of the shape-memory alloy (SMA) bolts, the SMA bolt type, and the sloping angle of the wedge-shaped friction plates on the damper performance. An analytical model is proposed for quantification of the hysteretic behavior of the damper. The test results showed that the damper specimens exhibited the expected multistage energy-dissipation characteristics and stable flag-shaped hysteretic curves with full self-centering behavior. A good energy dissipation capacity with an equivalent viscous damping (EVD) of about 20% was observed, which basically was consistent over the entire loading stages. The overall behavior of the damper was related closely to the aforementioned test parameters, indicating that the damper performance can be adjusted flexibly according to various seismic design requirements. The analytical predictions and the test results of the damper were in good agreement, indicating that the developed analytical model can be used confidently by engineers for the design of the developed damper. [ABSTRACT FROM AUTHOR]

This paper proposes an innovative hybrid timber beam-to-steel column connection for seismic design of multistory buildings. This innovative connection consists of a set of two U-shaped steel fuses connecting a glulam beam to a steel column. U-shaped fuses are designed to dissipate seismic-induced energy and can be replaced after a moderate or potentially strong seismic event. Eight full-scale experiments were conducted, involving four glulam beam specimens with varying thicknesses and eight pairs of fuses with two U-shaped plate configurations (open-fuse and closed-fuse). The key connection performance metrics, including the flexural stiffness and strength, hysteresis response, ductility, and energy dissipation capacity, were investigated using the test results. A set of mechanics-based equations is proposed to estimate flexural stiffness and strength of the connection. The results of the experimental program confirmed that the proposed hybrid connection exhibits a stable hysteresis response without noticeable strength degradation and possesses excellent ductility and energy dissipation capacities. Furthermore, the proposed mechanics-based equations can predict the moment capacity of the connection with sufficient accuracy. [ABSTRACT FROM AUTHOR]

The Morison equation is extensively employed to consider viscous effects in hydrodynamic investigations of diverse wave energy converters using the boundary element method (BEM). Nonetheless, linearizing the nonlinear drag component in frequency-domain analysis and determining the appropriate drag coefficients present a challenge. This paper proposes a simple method using the completely linear form of the artificial damping torque equation to consider the energy dissipation due to viscosity in the frequency-domain BEM analysis of bottom-hinged oscillating surge wave energy converters (OSWECs) under regular waves. Similar to the drag coefficient, a constant artificial damping ratio demonstrates applicability across various wave periods for a given OSWEC, with its most pronounced effects observed near the natural periods. Through scanning different values, the fittest artificial damping ratio is determined by minimizing the deviation between the BEM responses and the experimental or high-fidelity computational fluid dynamics data. In contrast to the widely varying drag coefficients, the fittest artificial damping ratios for three OSWECs with different dimensions fall within a narrow range. Hence, a recommended artificial damping ratio is proposed for the rapid approximate estimation of responses, particularly in the absence of validation data during the initial design phase. [ABSTRACT FROM AUTHOR]

The frame beam anchor plate is a new supporting structure reinforcing fill slopes. At present, only a few studies have evaluated its static stability based on the two-dimensional plane assumption. In this paper, the limit analysis method is combined with the three-dimensional spiral failure mechanism to evaluate the factor of safety (Fs) of a slope supported by a frame beam anchor plate. The pseudo-static approach is used to express the seismic effects. When calculating the internal energy dissipations, both the pull-out failure of anchor plates and tensile failure of tie rods are considered. The accuracy of the approach is verified by comparison with calculation results from the finite element method. Parameter analysis summarizes the influence law of each supporting structure design parameter on the Fs. Therefore, this study develops a theoretical basis for evaluating slope stability reinforced by frame beam anchor plates, which can better guide the design of slopes reinforced by this supporting structure. [ABSTRACT FROM AUTHOR]