scholarly journals A dynamic magnetic tension force as the cause of failed solar eruptions

Nature ◽  
2015 ◽  
Vol 528 (7583) ◽  
pp. 526-529 ◽  
Author(s):  
Clayton E. Myers ◽  
Masaaki Yamada ◽  
Hantao Ji ◽  
Jongsoo Yoo ◽  
William Fox ◽  
...  
2013 ◽  
Vol 41 (1) ◽  
pp. 60-79 ◽  
Author(s):  
Wei Yintao ◽  
Luo Yiwen ◽  
Miao Yiming ◽  
Chai Delong ◽  
Feng Xijin

ABSTRACT: This article focuses on steel cord deformation and force investigation within heavy-duty radial tires. Typical bending deformation and tension force distributions of steel reinforcement within a truck bus radial (TBR) tire have been obtained, and they provide useful input for the local scale modeling of the steel cord. The three-dimensional carpet plots of the cord force distribution within a TBR tire are presented. The carcass-bending curvature is derived from the deformation of the carcass center line. A high-efficiency modeling approach for layered multistrand cord structures has been developed that uses cord design variables such as lay angle, lay length, and radius of the strand center line as input. Several types of steel cord have been modeled using the developed method as an example. The pure tension for two cords and the combined tension bending under various loading conditions relevant to tire deformation have been simulated by a finite element analysis (FEA). Good agreement has been found between experimental and FEA-determined tension force-displacement curves, and the characteristic structural and plastic deformation phases have been revealed by the FE simulation. Furthermore, some interesting local stress and deformation patterns under combined tension and bending are found that have not been previously reported. In addition, an experimental cord force measurement approach is included in this article.


Materials ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 2087 ◽  
Author(s):  
Danhui Dan ◽  
Pengfei Jia ◽  
Guoqiang Li ◽  
Po Niu

It is typically difficult for engineers to detect the tension force of prestressed tendons in concrete structures. In this study, a smart bar is fabricated by embedding a Fiber Bragg Grating (FBG) in conjunction with its communication fiber into a composite bar surrounded by carbon fibers. Subsequently, a smart composite cable is twisted by using six outer steel wires and the smart bar. Given the embedded FBG, the proposed composite cable simultaneously provides two functions, namely withstanding tension force and self-sensing the stress state. It can be potentially used as an alternative to a prestressing reinforcement tendon for prestressed concrete (PC), and thereby provide a solution to detecting the stress state of the prestressing reinforcement tendons during construction and operation. In the study, both the mechanical properties and sensing performance of the proposed composite cable are investigated by experimental studies under different force standing conditions. These conditions are similar to those of ordinary prestressed tendons of a real PC components in service or in a construction stage. The results indicate that the proposed smart composite cable under the action of ultra-high pretension stress exhibits reliable mechanical performance and sensing performance, and can be used as a prestressed tendon in prestressed concrete structures.


CI-TECH ◽  
2021 ◽  
Vol 2 (01) ◽  
pp. 30-36
Author(s):  
Nugroho Utomo

Goods movement using container are quite efficiently assessed because it can carry a great amount of goods fit to container capacity. Freight transportations is a primary component of all supply-chain and logistics systems, but in contrary using a truck as its transportation means causing many problems such as air and noise pollutions, traffic congestions, road accidents and road damage.  Depart from this facts, so government is looking for another means of freight transporter which more efficient with a bigger load capacity advantages. This options goes to train as a solutions of intermodal freight transportations lack. In order to supporting intermodal freight transportations, right now double track of railway is available for Jakarta – Surabaya route (Northern line route).  By now, noted that freight transportation with double track railway frequency is potentially increase to 15 trip per days with capacity 500 TEU (Twenty feet Equivalent Units) per days and fuel consumptions (with truck) can be thrifted into 115 kl per days also reducing carbon monoxide emission amounts 350 tons per days.  According with an official statements from Directorate General of Railways, Ministry of Transportations, explained that Jakarta – Bojonegoro route on double track railway is fully operated so this paper is conducted to determining feasibility of railway structure performance due to freight intermodal transportations at Bojonegoro – Kalitidu route. Railway structure performance feasibility is observed from loading distributions, rail strength, rail sleeper strength, and railway subgrade endurance to planned freight trains.  As a result of this research obtained that tension force that occurred on rail is 830,10 kg/cm2 <  permitted tension on rail (first class rail) 1325 kg/cm2. So, tension force that occurred on rail is safe. Moment force that occurred on rail bottom is 14521,25 kg.cm < permitted moment force (150.000 kg.cm) Moment force that occurred in the middle of rail sleeper is 58993,978 kg.cm < permitted moment force (93000 kg.cm). Tension force that occurred on above railway subgrade (σ2) is 4,17 kg/cm2 < qu (29,671 kg/cm2). It means that railway subgrade is capable to supporting load of freight transportation operations along Bojonegoro – Kalitidu route.


2020 ◽  
Vol 142 (4) ◽  
Author(s):  
Hui Cheng ◽  
Karl Gunnar Aarsæther ◽  
Lin Li ◽  
Muk Chen Ong

Abstract Compared with the multipoint mooring fish cage, the single-point mooring (SPM) fish cage can spread out the fish wastes and uneaten feeds in a larger area, and it can also prevent the local environment from being overwhelmed. Thus, it has attracted much attention recently. In this research, different deformation-suppression methods are applied to the SPM system with a typical Norwegian fish cage aiming to increase the cultivation volume under the action of current and/or wave loads. A well-validated software, fhsim, is used to conduct the full-scale numerical study. The effects of the three deformation-suppression methods, i.e., (i) adding the lower bridles, (ii) adding the frontal rigid frame and (iii) adding the trawl doors, are analyzed under pure current and combined wave–current conditions. The results indicate that all the three deformation-suppression methods can improve the cultivation volume at least by 32% compared to the original SPM fish cage when the current velocity is larger than 0.5 m/s. In addition, moving the conjunction point close to the bottom ring can bring a positive effect on the cultivation volume maintaining with an only small increment in the tension force. This study can provide practical advice and useful guides for the SPM fish cage design.


2020 ◽  
Vol 642 ◽  
pp. A3 ◽  
Author(s):  
I. Zouganelis ◽  
A. De Groof ◽  
A. P. Walsh ◽  
D. R. Williams ◽  
D. Müller ◽  
...  

Solar Orbiter is the first space mission observing the solar plasma both in situ and remotely, from a close distance, in and out of the ecliptic. The ultimate goal is to understand how the Sun produces and controls the heliosphere, filling the Solar System and driving the planetary environments. With six remote-sensing and four in-situ instrument suites, the coordination and planning of the operations are essential to address the following four top-level science questions: (1) What drives the solar wind and where does the coronal magnetic field originate?; (2) How do solar transients drive heliospheric variability?; (3) How do solar eruptions produce energetic particle radiation that fills the heliosphere?; (4) How does the solar dynamo work and drive connections between the Sun and the heliosphere? Maximising the mission’s science return requires considering the characteristics of each orbit, including the relative position of the spacecraft to Earth (affecting downlink rates), trajectory events (such as gravitational assist manoeuvres), and the phase of the solar activity cycle. Furthermore, since each orbit’s science telemetry will be downloaded over the course of the following orbit, science operations must be planned at mission level, rather than at the level of individual orbits. It is important to explore the way in which those science questions are translated into an actual plan of observations that fits into the mission, thus ensuring that no opportunities are missed. First, the overarching goals are broken down into specific, answerable questions along with the required observations and the so-called Science Activity Plan (SAP) is developed to achieve this. The SAP groups objectives that require similar observations into Solar Orbiter Observing Plans, resulting in a strategic, top-level view of the optimal opportunities for science observations during the mission lifetime. This allows for all four mission goals to be addressed. In this paper, we introduce Solar Orbiter’s SAP through a series of examples and the strategy being followed.


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