scholarly journals Seismic Performance and Strengthening of Purlin Roof Structures Using a Novel Damping-Limit Device

2021 ◽  
Vol 8 ◽  
Author(s):  
Baokui Chen ◽  
Bao Jia ◽  
Ming Wen ◽  
Xiaodong Li
Keyword(s):  
Seismic Performance ◽  
Rural Areas ◽  
Structural Parameters ◽  
Local Stress ◽  
The Novel ◽  
Reinforcement Effect ◽  
Seismic Capacity ◽  
Novel Device ◽  
Roof Structure ◽  
Strengthening Method

Purlin roof structure houses, which have the advantages of readily accessible materials and simple construction, are widely used in rural areas of China. However, during earthquakes, the wooden purlins tend to fall off and the walls crack. Therefore, it is necessary to monitor the structural parameters of and strengthen the anti-seismic capacity of these structures. To compensate for the seismic deficiencies of the purlin roof structure, a novel damping-limit device installed at the connection position of the gable and the wooden purlin was proposed. In this study, the seismic performance and reinforcement effect of the brick-wood structure with the purlin roof were analyzed through numerical simulation. The research results indicate that the novel damping-limit device proposed in this study can significantly reduce the local stress concentration and the seismic response of the structure, and thereby rectifying the seismic defect of falling purlin. Moreover, compared with the traditional strengthening method, the novel device is more convenient to install and the reinforcement quality is easier to ensure.

Measuring Earwax Cortisol Concentration Using a Non-Stressful Method (Preprint)

2020 ◽  
Author(s):  
Andrés Herane-Vives
Keyword(s):  
Cortisol Level ◽  
Local Stress ◽  
Extraction Methods ◽  
Cortisol Concentration ◽  
The Novel ◽  
Sampling Device ◽  
Related Factors ◽  
Novel Device ◽  
Cortisol Levels ◽  
The Right

BACKGROUND “Short-term” samples are not the most appropriate for reflecting Chronic Cortisol Concentration (CCC). Although hair is used for reflecting the systemic cortisol level over “long-term”, its use appears clinically problematic. Local stress and non-stress related factors may release a circumscribed cortisol secretion that is accumulated in hair. Non-stressful earwax extraction methods may provide a more accurate specimen to measure CCC. OBJECTIVE Correlate cortisol levels using hair, serum and earwax samples METHODS Earwax from both ears of 37 controls were extracted using a clinical procedure commonly associated with local pain. One month later, earwax from the left ear side was extracted using the same procedure, and earwax from the right ear side was comfortably extracted, using an earwax self-sampling device. Participants also provided one centimetre of hair that represented the retrospective month of cortisol output, and one serum sample that reflected the effect of systemic stressors on cortisol levels. Earwax (ECC), Hair (HCC) and Serum (SCC) Cortisol Concentration were correlated and compared. Confounders´ effect on cortisol levels were studied. RESULTS Serum showed the largest and hair the lowest cortisol concentration (p<0.01). Left-ECC was larger than Right-ECC (p=0.03). Right-ECC was the only sample unaffected by confounders (all p>0.05). Right-ECC and HCC showed the only significant association (r=0.39; p=0.03). CONCLUSIONS The self-sampling device did not represent a local stressor for the ceruminous glands. It provided the cortisol level with the least likely to be affected by confounding factors over the previous month. ECC using the novel device may constitute another accurate, but more suitable and affordable specimen for measuring CCC.

scholarly journals Seismic Performance of Steel Box Bridge Piers with Earthquake-Resilient Function

2020 ◽  
Vol 2020 ◽  
pp. 1-24
Author(s):  
Haifeng Li ◽  
Wenwei Luo ◽  
Jun Luo
Keyword(s):  
Energy Dissipation ◽  
Bearing Capacity ◽  
Seismic Performance ◽  
Seismic Behavior ◽  
Bridge Pier ◽  
Steel Bridge ◽  
Deformation Capacity ◽  
The Novel ◽  
Seismic Capacity ◽  
Energy Dissipated

A novel steel box bridge pier with replaceable energy dissipation wall plates at the base was proposed. After moderate earthquakes, the damaged energy dissipation wall plates and constraining steel plates on the two sides could be rapidly replaced, while the entire energy-dissipated column at the base can also be replaced after rare earthquakes. In this way, the seismic capacity of the new type of steel box bridge pier could be restored after earthquakes. For the purpose of discussing the seismic performance of this novel steel box-shaped bridge pier, the pseudostatic test and numerical simulation were performed. The results showed that the failure of the specimens in the pseudostatic tests occurred predominantly in the energy dissipation zone at the base. After replacing the damaged energy-dissipated column at the base, the seismic behavior of the proposed steel bridge pier can be recovered rapidly. Axial compression ratio is an important factor influencing the seismic behavior of the novel steel box bridge pier. The strength of the energy dissipation wall plates influences the novel steel box-shaped bridge pier’s bearing capacity and deformation capacity. Spacing between the horizontal stiffening ribs had little impact on the bearing capacity and deformation capacity of the proposed steel bridge pier. The larger the thickness of the energy dissipation wall plate, the higher the bearing capacity and deformation capacity of the steel box bridge pier. Finally, an empirical equation for the design of this novel steel bridge pier under cyclic loading was proposed.

Research on Shaking Table Test of Masonry Building with Rowlock Cavity Walls

2011 ◽  
Vol 250-253 ◽  
pp. 1196-1205
Author(s):  
Zhong Fan Chen ◽  
Fei Lu ◽  
Yang Yuan ◽  
Sha Sha Miao
Keyword(s):  
Seismic Performance ◽  
Structural Parameters ◽  
Research Result ◽  
Load Condition ◽  
Shaking Table ◽  
Cavity Wall ◽  
Wall Structure ◽  
Masonry Building ◽  
Model Structure ◽  
Seismic Capacity

Rowlock cavity wall was widely used in rural house in Southern Jiangsu Province from 1980s to 1990s. As one type of masonry structures, the seismic performance of rowlock cavity wall has rarely been studied on. Based on the report of General Seismic Investigation in Jiangsu Qidong, one 1/2-scale rowlock cavity wall structure was modeled as the existing rural house, and was tested on shaking table in lab of Southeast University. After analyzing the failure state of the model, and examining the structural parameters such as natural frequency, damping ratio, floor acceleration, floor shift, strain and crack of the model in load condition of different earthquake wave and intensity, the seismic performance of rowlock wall structure was assessed. And the seismic capacity of the whole model and each piece of rowlock wall was also analyzed. Based on the mortar strength field inspected in model wall, the seismic capacity of model structure under the action of rarely occurred earthquake of level 6 seismic precautionary intensity was estimated. The result showed that the model structure would collapse under the load condition. Obviously, this can not satisfy the seismic precautionary requirement in Code for Seismic Design of Buildings (GB50011-2001). Therefore, some principal reinforcement suggestions were discussed and proposed for existing rowlock cavity wall buildings. The research result of this paper could provide some theoretical foundation for the Aseismic Residential Project of rural peasant house, and also could be referred to for further research on rowlock cavity wall structures.

Nonlinear resonance in Anaconda

2014 ◽  
Vol 750 ◽  
pp. 507-517 ◽  
Author(s):  
Chiang C. Mei
Keyword(s):  
Water Waves ◽  
Structural Parameters ◽  
Nonlinear Resonance ◽  
Wall Friction ◽  
Tube Length ◽  
Rubber Tube ◽  
The Novel ◽  
Power Flux ◽  
Novel Device ◽  
Further Development

AbstractA nonlinear theory is developed for a recent wave energy converter design inspired by the mechanics of animal arteries. The device is a long and hollow rubber tube immersed beneath the sea surface. Excited by passing water waves outside, pressure waves are resonated inside the tube and advance toward the stern to spin a turbine for power production. To account for significant magnification, the classical linear theory of blood vessels is modified. Diffraction is neglected but nonlinearity and wall friction are included. The spatial evolution of harmonic amplitudes is shown to be governed by a dynamical system similar to that in nonlinear optics. The maximum available power flux is predicted as a function of the tube length and other structural parameters. It is hoped that the theory may assist further development of the novel device.

Study on the Seismic Performance of Rural Buildings in Beijing Area

2013 ◽  
Vol 353-356 ◽  
pp. 2397-2401
Author(s):  
Cheng Bin Liu ◽  
Ya Ling Ou ◽  
Xing Chen Dong ◽  
Yi Kui Zhang ◽  
Xiang Xiang Zhang ◽  
...  
Keyword(s):  
Seismic Response ◽  
Seismic Performance ◽  
Rural Areas ◽  
Masonry Structure ◽  
Earthquake Damage ◽  
Masonry Structures ◽  
Seismic Capacity ◽  
Beijing Area ◽  
Rural Buildings ◽  
The Subject

Wenchuan earthquake caused huge losses in rural areas. The subject briefly introduced the earthquake damage characteristics of masonry structures, analyzed the earthquake damage reasons. The main purpose is to propose some measures to improve the seismic capacity of rural buildings in Beijing area. Through two seismic fortification measures, can effectively enhance the integrity of the masonry structure, reduce the seismic response, effectively improve the seismic capacity of the structure.

EFFICACY OF A NOVEL DEVICE TO DETECT, ALERT AND RESOLVE NEONATAL APNEA - PILOT STUDY

2019 ◽  
Vol 9 (9) ◽  
pp. 608-613
Author(s):  
Dr. Swapna Lingaldinna,Dr. Himabindu Singh,Mona Sharma*
Keyword(s):  
Newborn Care ◽  
Standard Of Care ◽  
The Novel ◽  
Tertiary Referral ◽  
Tertiary Referral Hospital ◽  
Care Community ◽  
Novel Device ◽  
Sick Newborn ◽  
Central Apneas ◽  
Neonatal Apnea

Objective: To measure the accuracy of a novel device in detecting Bradycardia andDesaturation (B&D) events and to determine its efficacy in resolving apneas innewborns with comparison to standard monitor (which only detects B&D eventsand alerts).Design: This was a prospective observational study.Setting: Sick Newborn Care Unit of a large tertiary referral hospital in Hyderabad,India.Methods: 31 newborns were provided with a novel device, which monitored oxygensaturation and pulse rate and alarmed when values dropped below a set thresholdwhich is referred as an event, henceforth. The novel device also provided footstimulation in response to above-mentioned events. When the monitor alarmed, anurse attended to the baby to confirm whether the baby was breathing and whetherthe event had been resolved by the device. If the event had not resolved, appropriateaction as per the standard-of-care was performed.Results: The novel device “ApneBootTM” positively detected B&D events 94.03% oftimes as compared to the standard reference monitor. 56 of 67 observed B&D eventswere visually confirmed to be apneas, indicating that 83.6% of B&D eventscoincided with apneas. Of the 56 apneic events, 50 were central apneas, of which 35were resolved by the novel device, making the device’s efficacy of apnea resolution70%.Conclusion: The results of the study indicate that this novel device “ApneBootTM”is very effective in detecting and alarming B&D events, which coincides with theapnea, and resolving it by providing foot stimulation.Keywords: Novel Device, Neonatal Apnea, Low Birth Weight, Body Temperature,Kangaroo Mother Care, Community Health,

SEISMIC CAPACITY OF MEDIUM SIZE CONTINUOUS BRIDGES WITH LEAD-RUBBER BEARINGS

2019 ◽  
Vol 3 (Special Issue on First SACEE'19) ◽  
pp. 199-206
Author(s):  
Bertha Olmos ◽  
José Jara ◽  
José Luis Fabián
Keyword(s):  
Seismic Performance ◽  
Seismic Vulnerability ◽  
Base Isolation ◽  
Elastic Behaviour ◽  
Medium Size ◽  
Nonlinear Behaviour ◽  
Seismic Capacity ◽  
Damage Scenarios ◽  
Isolation Systems ◽  
Rubber Bearings

This paper investigates the effects of the nonlinear behaviour of isolation pads on the seismic capacity of bridges to identify the parameters of base isolation systems that can be used to improve seismic performance of bridges. A parametric study was conducted by designing a set of bridges for three different soil types and varying the number of spans, span lengths, and pier heights. The seismic responses (acceleration, displacement and pier seismic forces) were evaluated for two structural models. The first model corresponded to the bridges supported on elastomeric bearings with linear elastic behaviour and the second model simulated a base isolated bridge that accounts for the nonlinear behaviour of the system. The seismic demand was represented with a group of twelve real accelerograms recorded on the subduction zone on the Pacific Coast of Mexico. The nonlinear responses under different damage scenarios for the bridges included in the presented study were estimated. These results allow determining the seismic capacity of the bridges with and without base isolation. Results show clearly the importance of considering the nonlinear behaviour on the seismic performance of bridges and the influence of base isolation on the seismic vulnerability of medium size bridges.

scholarly journals Strengthening Effect of the External Prestressing Method That Simulated a Deterioration Bridge

2021 ◽  
Vol 11 (6) ◽  
pp. 2553
Author(s):  
Sang-Hyun Kim ◽  
Jong-Sup Park ◽  
Woo-Tai Jung ◽  
Jae-Yoon Kang
Keyword(s):  
Compressive Strength ◽  
Strengthening Effect ◽  
Reinforcement Effect ◽  
Loading Test ◽  
Yield Load ◽  
Existing Structures ◽  
External Prestressing ◽  
The Difference ◽  
Existing Structure ◽  
Strengthening Method

Various methods for strengthening existing structures have been developed owing to the increase in human and property damages caused by the deterioration of structures. Among the various reinforcing methods, the external prestressing method increases the usability and safety of a structure by directly applying tension to the weak tensile area that suffers the greatest deflection during the structure usage. The external prestressing method is advantageous in reducing cracks caused by the introduced tension and restoration of the deflection. Since the strengthening method is applied to deterioration bridges, the strengthening effect is affected by the condition of the existing structure. However, studies on the strengthening effect according to the degree of deterioration are insufficient. Therefore, the behavior according to the strengthening status was analyzed, and the strengthening effect was identified in this study by simulating the deteriorated bridge, reducing the compressive strength and reinforcement quantity, and conducting a four-point loading test. As a result of the experiment, a reinforcement effect of 215% crack load, 161% yield load, and the difference in behavior according to the reinforcement parameters were confirmed.

scholarly journals Rise-Up mist-netting (RUM): a mobile protocol for trapping wary territorial birds

2021 ◽  
Vol 61 ◽  
pp. e20216110
Author(s):  
Paulo Sérgio Amorim ◽  
Mariana Fonseca Rossi ◽  
André de Camargo Guaraldo
Keyword(s):  
Urban Area ◽  
Rural Areas ◽  
Urban Areas ◽  
General Public ◽  
Bird Species ◽  
Breeding Period ◽  
The Novel ◽  
Limited Space ◽  
Trapping Methods ◽  
Visual Impacts

Many bird species avoid traditional traps such as mist nets, thus alternative trapping methods are often needed. The Rufous Hornero (Furnariidae: Furnarius rufus) is one such species that was captured so far using conventional mist netting in rural areas or using nest-targeted traps, which risk nest damage and abandonment. Here we describe the novel rise-up mist-netting (RUM) protocol and its catchability for the wary and territorial Rufous Hornero in an urban area. The RUM trap allowed us quickly capturing 40 Rufous Hornero individuals even in paved parking lots and streets during the bird’s breeding period. The RUM is an active and targeted protocol that demands a single and quickly trainable field assistant. Therefore, it should also enable the capture of many understudied territorial but wary species. Moreover, it has enough mobility to fit studies in urban areas, and whenever researchers may deal with limited space and, at the same time, should reduce negative visual impacts to the general public of birds’ capturing and banding procedures.

scholarly journals Modeling and Dynamic Characteristics of a Novel High-Pressure and Large-Flow Water Hydraulic Proportional Valve

Machines ◽  
2022 ◽  
Vol 10 (1) ◽  
pp. 37
Author(s):  
Heng Zhang ◽  
Yaoyao Liao ◽  
Ze Tao ◽  
Zisheng Lian ◽  
Ruihao Zhao
Keyword(s):  
High Pressure ◽  
Structural Parameters ◽  
Nonlinear Flow ◽  
Step Response ◽  
Main Stage ◽  
The Novel ◽  
Mining Equipment ◽  
Closing Time ◽  
Proportional Valve ◽  
Large Flow

In the field of fully mechanized coal mining equipment, the hydraulic valve used in the hydraulic support is an on/off directional valve. There are many problems caused by the valve such as large pressure shock and discontinuous flow control. Therefore, a novel two-position three-way hydraulic proportional valve suitable for high-pressure and large-flow conditions is proposed to overcome the above problems. The novel valve utilizes a two-stage structure and the displacement follow-up principle is adopted between the pilot stage and the main stage to meet proportional control. In this paper, a simulation model of the novel proportional valve was established after a simplified analysis of the structural principle. Its reliability and the feasibility of the design were verified by the test results under different working conditions. Then, the step response characteristics of the proportional valve under different strokes were predicted and analyzed. Nonlinear characteristics were presented, and the closing time was shorter than the opening time because of the influence of nonlinear flow force. Under different ramp signals, the displacement of the main inlet spool was always approximately equal to the displacement of the pilot stage. Then, the motion relationship between the pilot stage and the main stage was studied, and the influence of the structural parameters on the stability was analyzed.

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