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The stability of boom operation directly affects the operational safety of the spider aerial work platform. Taking the model SPA33HJ spider aerial work platform from SINO-BOOM as an example, its boom structure and working principle are introduced, the factors that causes the shake of the boom are systematically analyzed, and the main measures and methods for eliminating the shake of the boom are elaborated, which provides a reference for solving the boom shake problem of the spider aerial work platform. [ABSTRACT FROM AUTHOR]

The stability of boom operation directly affects the operational safety of the spider aerial work platform. Taking the model SPA33HJ spider aerial work platform from SINO-BOOM as an example, its boom structure and working principle are introduced, the factors that causes the shake of the boom are systematically analyzed, and the main measures and methods for eliminating the shake of the boom are elaborated, which provides a reference for solving the boom shake problem of the spider aerial work platform. [ABSTRACT FROM AUTHOR]

No attention has been given in previous studies to understand the influence of the sophistication of the soil constitutive model on the response of buried concrete pipes subjected to transverse seismic effect. This research, therefore, has been conducted to address this gap in knowledge by analyzing the behavior of a buried concrete pipe subjected to transverse seismic shake employing the linear elastic (LE) model, elasto-plastic Mohr-Coulomb (MC) model, hardening soil (Hs) model, and hardening soil model with small strain stiffness (Hs small) to provide a benchmark study that helps the designers and the researchers to select the most suitable and less computationally demanding soil constitutive model. The cases of good and poor installation conditions have been considered in the analyses. In addition, numerous earthquake records have been used to allow the consideration of wide range of earthquake intensities to aid general conclusions. It was found that all of the considered constitutive models produce the same trend of the circumferential bending moment (BM) that is developed around the pipe. In general, the maximum BM produced using the LE and MC models is significantly lower than that produced using the Hs and Hs small models with one exception for the LE model for a predominant frequency of 0.66 Hz. Furthermore, the maximum BM produced using the LE and MC models is not sensitive to the increase of the peak ground acceleration (PGA). More importantly, the Hs and Hs small models produce almost similar results with a percentage difference ranges between 1% to 9%. In addition, the Hs and Hs small models show a decrease of the maximum BM as the predominant frequency rises and an increase of the maximum BM as the PGA rises.

Origami structures can transform their form and function by changing the direction of their folds. This reconfiguration can enable multifunctional robots, but doing so requires a fast, robust, and repeatable actuation method. In this article, we present an origami gripper that uses dynamic transformation to change its kinematic behavior in less than a second. We characterize individual vertices to show that the transformation is predictable and repeatable for different designs and orientations. We then apply it to a multivertex template that is capable of a wide range of shapes and motion patterns, indicating that transformation can be generalized to complex and functional machines. To demonstrate this, we built a transforming origami gripper on a robotic arm to pick up multiple objects. Demonstrations show that the gripper can quickly reconfigure between three different grasping modes and has sufficient stiffness to engage with and lift multiple objects with distinct geometries.

On 9 April 1945, less than a month before the end of hostilities in Europe, a young Luftwaffe pilot named Hans Guido Mutke put his jet-propelled Messerschmitt Me 262 fighter-bomber into a steep dive, intending to come to the aid of a fellow airman below.As the Messerschmitt accelerated downward, the plane began to shake violently, and the controls became unresponsive. Mutke managed to regain control and lived to describe the incident, in which he later laid claim to having exceeded the speed of sound, a controversial but plausible assertion.

In molecular dynamics simulations we can often increase the time step by imposing constraints on bond lengths and bond angles. This allows us to extend the length of the time interval and therefore the range of physical phenomena that we can afford to simulate. We examine the existing algorithms and software for solving nonlinear constraint equations in parallel and we explain why it is necessary to advance the state-of-the-art. We present ILVES-PC, a new algorithm for imposing bond constraints on proteins accurately and efficiently. It solves the same system of differential algebraic equations as the celebrated SHAKE algorithm, but ILVES-PC solves the nonlinear constraint equations using Newton's method rather than the nonlinear Gauss-Seidel method. Moreover, ILVES-PC solves the necessary linear systems using a specialized linear solver that exploits the structure of the protein. ILVES-PC can rapidly solve constraint equations as accurately as the hardware will allow. The run-time of ILVES-PC is proportional to the number of constraints. We have integrated ILVES-PC into GROMACS and simulated proteins of different sizes. Compared with SHAKE, we have achieved speedups of up to 4.9× in single-threaded executions and up to 76× in shared-memory multi-threaded executions. Moreover, ILVES-PC is more accurate than P-LINCS algorithm. Our work is a proof-of-concept of the utility of software designed specifically for the simulation of polymers. This work has been partially supported by the Spanish Ministry of Science and Innovation MCIN/AEI/10.13039/501100011033 (contracts PID2019-107255GB-C21, PID2019-105660RB-C21, and PID2019-107293GB-I00), by the Generalitat de Catalunya (contract 2017-SGR-1328), by the Gobierno de Aragón (E45_20R T58_20R research groups), and by Lenovo-BSC Contract-Framework Contract (2020). Santiago Marco was supported by the Agencia Estatal de Investigación (Spain) under Juan de la Cierva fellowship grant IJC2020-045916-I. Miquel Moretó was partially supported by the Agencia Estatal de Investigación (Spain) under Ramón y Cajal fellowship number RYC-2016-21104. Carl Christian Kjelgaard Mikkelsen is supported by eSSENCE, a collaborative e-Science programme funded by the Swedish Research Council within the framework of the strategic research areas designated by the Swedish Government.

The restaurant industry is one of the largest and fastest growing sectors in the economy in the United States. According to the National Restaurant Association (NRA), the food service industry is the third largest industry accounting for more than 4% of the country’s gross domestic product (GDP). Shake Shack is an American fast food restaurant chain based in New York City. It started out as a food cart at Madison Square Park in 2000, and its popularity grew steadily. Shake Shack is currently one of the best fast-food restaurants in the world. This article discusses the successful business model of Shake Shack through IPO analysis.

To understand the mechanism of ring shakes in Dahurian larch (Larix gmelinii), the ring shake surface on the tangential section was observed and compared with the shear surface of green and air-dry wood. Macroscopically, the ring shakes occurred in the heartwood between the 20th and 40th growth ring. The ring shake surface exhibited an even and clean structure without the fluff. The shear surface of the green wood showed a larger amount of fluff compared to that of air-dry wood. In microscopy, ring shake failure occurred at the end of the latewood and/or the beginning of earlywood or within the earlywood zone. The ring shake surface was covered with a resinous substance, and the wood cells were observed after removing the resinous substance with ethanol. The tracheid walls in the ring shake and shear surface of green wood primarily exhibited intercell failure and rarely intrawall and transwall failures. In air-dry wood, the tracheid walls in the shear surface mostly exhibited intrawall and transwall failures. In the ring shake surface, there was hardly any failure in the epithelial and ray cells, thereby showing a distinct difference compared to the shear surface of the green and air-dry woods.

The response spectral ratio (RSR) used to construct a design spectrum that incorporates site effects is conventionally assumed to be independent of an earthquake scenario in linear analysis. However, recent studies have found that the RSR varies significantly with an earthquake scenario, even in linear analysis. In this study, an analytical RSR model that incorporates the effect of an earthquake scenario is proposed. To this end, the mechanism behind the effect of earthquake scenarios, i.e., the variation in the RSR with an earthquake scenario, is systematically investigated by comparisons with the scenario-independent Fourier spectral ratio based on random vibration theory. The proposed RSR model is verified by comparing its results with those obtained from a SHAKE analysis considering a variety of actual soil conditions. Based on the proposed RSR model, the design spectrum incorporating site effects can be reasonably and easily constructed.

Automated stocker system is widely used in semiconductor and liquid crystal display (LCD) industries for handling and storage of valuable wafers or glass panels. Massive front opening unified pods (foups) containing wafers, or cassettes storing glass panels, are placed in shelf stockers during manufacturing. Although several preventative measures have been taken, during the past earthquakes, substantial financial loss from the industries were reported, and one of the main causes was attributed to collision of the foups or cassettes and shake off from the shelfs. This paper proposes a methodology of incorporating viscous fluid dampers into the stokers to mitigate their seismic response. Unlike conventionally been done in buildings where dampers are placed between adjacent stories, it is proposed to install dampers in between the ceiling and top of the stocker. Such configuration utilizes the large velocity at the stocker top under vibration, resulting in smaller damper size, and enables a leverage mechanism that requires smaller damper force to resist the stocker’s vibration. Both shake table tests and simulation of a full-scale stocker under realistic earthquakes have been conducted. Results indicate that both displacement and acceleration responses of the stocker can be significantly reduced, and dynamic response of the stocker under seismic excitations can be well predicted.

After initially pitting partisans against purists, the literature on the ethics of fandom has coalesced around a pluralist position: purists and partisans each have their own merits, and there is n...

In order to overcome the problems of long analysis time, low accuracy, and high energy consumption in traditional lateral vibration analysis methods of high-rise buildings, a new method of lateral vibration analysis of high-rise buildings based on partial differential equation is proposed. Based on Hamilton’s principle, the partial differential equation of lateral vibration of high-rise buildings is established, and the Galerkin method is used to solve the partial differential equation until the discrete solution is obtained, and then the displacement response of high-rise buildings under different excitation frequencies is obtained. The experimental results show that compared with the traditional method, the proposed method has the advantages of short calculation time, high accuracy, and low energy consumption.

The small-scale unmanned aerial vehicle (UAV) helicopter has a complex structure, strong nonlinearity, coupling and open-loop instability, making it shake violently and even produce chaotic oscilla...

Raspberry Shake (RS) seismographs offer the potential for affordable and citizen-led seismic monitoring in areas with few publicly available seismometers, especially in previously quiescent regions experiencing induced seismicity. However, their scientific and regulatory potential remains largely untested. We examine the ground motions recorded by 11 RS and one broadband station within 15 km of the United Downs Deep Geothermal Power (UDDGP) project in Cornwall, United Kingdom, to evaluate the RS network’s suitability to provide an initial ground-motion assessment of the region. To date, the British Geological Survey (BGS) has reported 232 induced events originating at UDDGP since flow testing began in summer 2020, with two events exceeding local magnitude (ML) 1.5. Although the RS accelerometers are too noisy for UDDGP’s microseismic events, the vertical geophones are useful. Peak ground velocity observations are consistent with relevant ground-motion models, whereas peak ground acceleration (PGA) values are greater than predicted. Regional trends in the PGA levels are likely caused by path effects. Finally, RS estimates of ML are similar to those reported by the BGS. For sparse national seismic networks, RS stations can enable a preliminary evaluation of seismic events and their ground motions.

Crane girder is subject to alternating load in long time, which makes it prone to fatigue and fracture. Vision deflection measurement has become an effective method for structural health monitoring. However, crane girder does not always exhibit high contrast feature and artificial markers have to be pasted. Existing artificial markers cannot perform well in poor light conditions and the accuracy is limited. In this paper, we design an anti-interference marker by pasting a film onto a circular surface light source. The marker allows the vision system to work well under different light conditions. In addition, the reduction of camera shake and sub-pixel technique have been studied to improve the accuracy. According to the characteristics of the marker, corresponding image processing algorithms are also studied. Firstly, the designed marker can suppress environmental interference even at long distances with a wireless module and a small aperture. Secondly, the center of the marker in the image can be calculated using a sub-pixel detection technique. Finally, a camera shake reduction method is applied by using multiple reference markers and scale conversion factors are taken into account to get the physical displacement. To verify the measurement results, two experiments were carried out using a digital dial gauge sensor and laser displacement sensor for comparison. The experimental results proved the robustness and high precision of the vision system.

Smartphones equipped with motion sensors can be manipulated as a community seismic network for earthquake detection. But, there still have many challenges such as the limited sensing capability of the off-the-shelf sensors and unpredictable diversity of daily operations by phone users in current smartphones, which yield poor monitoring quality. So we present a suite of algorithms towards detecting anomalous seismic events from sampling data contaminated by users operations, including a lightweight signal preprocessing method, a two-phase events picking and timing scheme on local smartphones, and a decision fusion scheme to maximize anomaly detection performance at the fusion center while meeting the requirements on system false alarm rate. We experimentally evaluate the proposed approach on networked smartphones and shake tables. The results verify the effectiveness of our approach in distinguishing anomalous seismic events from noises due to the normal daily operation.

A cable-stayed pedestrian bridge with an S-curved girder called Shake Hands Bridge is proposed. This type of bridge overturns the traditional notion of linearly constructed cable-stayed bridges. Ca...

Ekşi Sözlük is one of the most visited websites in Turkey. Registered users of the website share their knowledge about any topic. In this study, we collect the user entries on the topic of 20 earthquakes in Turkey and the surrounding area. Entries with city and district level information are converted to intensity values. Shake maps of the earthquakes are created by using a ground motion to intensity conversion equation. User entries and created shake maps are compared. It is found that entries correlate with the predicted intensities. It is also found that local soil conditions and building types have an amplifier effect on entries on the website. Several entries on the earthquake topics have magnitude estimations. The difference between predicted and observed intensities also varies with distance. Users are able to predict the magnitudes of the earthquakes with ±0.54 misfit. This study shows that Ekşi Sözlük has the potential to be a reliable source of macroseismic intensity for the earthquakes in Turkey if the felt reports are collected with a predetermined format.

Centenaries are times to reflect and assess status. This essay discusses accounts of how the centenary of the Russian Revolution was marked around the globe by governments, national media and civil...

Video prediction has developed rapidly after the booming of deep learning. As an important part of unsupervised representation learning, it plays an important role in anomalous behavior detection, autonomous driving, video games, and other fields. However, the prediction method based on optical flow estimation is susceptible to brightness change and camera shake, and it is difficult to predict occluded objects. While the prediction method based on pixel generation is difficult to fit ambiguous and complex scenes, which leads to a blurry prediction. In this work, we proposed an end-to-end video prediction framework that combines the optical flow estimation module with the pixel generation module by a learnable mask weight to predict high-fidelity videos. To further improve the prediction effect, we introduce adversarial training to the framework. We introduced a frame discriminator and a sequence discriminator to ensure the consistency of the spatio-temporal distribution of predicted video frames and real video frames. The results of experiments on challenging datasets demonstrate the practicability and effectiveness of our proposed video prediction framework. On the one hand, our proposed framework has achieved an equal quality compared with the current latest model, which requires fewer parameters and has a faster prediction speed. On the other hand, the results of ablation experiments demonstrate the effect of fusing different modules and the effectiveness of adversarial training.

The micro-seismic hazard estimation including quantification of the ground motion amplification has been conducted at Ahmedabad city based on near-surface characterization/soil modeling. The city has experienced substantial damage in the course of the 2001 Bhuj earthquake. A total of 20 boreholes were drilled in the city up to the depths of 40–80 m. A five-fold methodology is adopted: (1) Assessment of the seismic perspective of the area under study, (2) demarcation of the engineering bed layer (EBL) through geophysical (seismic) surveys and the soil properties, (3) soil modeling using geotechnical and the geophysical parameters, (4) assessment of the strong ground motion at EBL through simulation considering far-field earthquake scenarios and near-field earthquakes scenario and (5) surface strong-motion estimation by ground response analysis based on equivalent-linear approach. The near-surface soil models were prepared from the borehole logs, shear-wave velocity estimated from the seismic survey and the soil properties like soil classification and density. The strong motion at EBL is computed by simulating seismotectonically justified scenario earthquakes through the stochastic finite-fault source modeling technique using the region-specific input parameters. The surface-strong motion is estimated by performing ground response analysis (with SHAKE) at every borehole using EBL-strong motion and prepared soil models. The EBL was found varying from 28 to 54 m in depth in Ahmedabad city. The effect of far-field and near-field earthquake sources was considered for assessing the hazard. To compensate for the uncertainty, a total of 108 and 81 input parametric combinations for near-field earthquake scenarios, and far-field earthquake scenarios, respectively have been considered for estimating the strong motion at EBL. The peak ground acceleration (PGA) of 52–111 cm/s2 and 108 cm/s2 are estimated at EBL due to near-field earthquake scenarios and far-field earthquake scenarios, respectively. The PGA through ground response analysis at surface level is found to be varying from 101 to 279 cm/s2 for near-field earthquake scenarios and, 118–161 cm/s2 for the far-field earthquake scenarios. The spectral acceleration (SA) (at surface level) has also been calculated for damping of 5%. The average SA distribution maps for 0.2 s (1–2 story), 0.55 s (4–5 story), 1 s (high rise) and 1.25 s period (large structures) have been prepared for both types of scenario earthquakes. The strong motion amplification is computed to be in the range of 1.6–3.3 for near-field earthquake scenarios and 2.2–3.0 for near-field earthquake scenarios.

This article discusses several arguments in favor of the hypothesis that the headshake as a gesture for negation has its origins in early childhood experiences. It elaborates on Charles Darwin’s observation that children inevitably shake their heads in order to stop food intake when sated, thereby establishing a connection between rejection and the head gesture. It is argued that later in life the semantics of the headshake extends from rejection to negation – just as it can be observed in the development of spoken language negation. While Darwin’s hypothesis can hardly be tested directly, this paper takes a novel perspective and looks at the predictions it makes taking a plethora of sources of evidence into account. The question of how head gestures are used in cultures where the headshake is not a sign for negation or where other negative head gestures are in use will also be discussed.

Several studies found that the probiotic bacterias such as Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 could prevent glycemia and control the blood lipid profiles. Currently, a probiotic product such as yogurt is not preferable by some consumers since the taste is sour. Therefore, this study was conducted to develop milkshakes supplemented by probiotics Lactobacillus acidophilus La5 and Bifidobacterium lactis Bb12 which are expected to be more acceptable and have a beneficial effect with the addition of prebiotics and soluble fiber glucomannan. This study aims to determine the effect of synbiotic shakes on fasting blood glucose levels and lipid profiles in hyperglycemia Wistar rat models. The study design was a pre-posttest controlled group with 48 male Wistar rats divided into 8 groups, namely the healthy control group (I); hyperglycemia control group (II); group III that received metformin; group IV that received synbiotic shake with La5 + FOS; group V that received synbiotic shake La5 + inulin; group VI that received synbiotic shake Bb12 + FOS; group VII that received synbiotic shake Bb12 + inulin; and group VIII that received synbiotic shake La5 + Bb12 + FOS. The dose of the intervention was 3.6 ml/day with an intervention duration of 28 days. The results showed that the differences in blood glucose levels were not significant (p> 0.05) except for groups IV and VI that experienced a significant increase (p