scholarly journals On the Frequency Drift of Coronal Loop’s Fast Kink Oscillation: Effects of Quasi-static Evolution in Loop Density

2021 ◽  
Vol 922 (2) ◽  
pp. 224
Author(s):  
Hongbo li ◽  
Hengqiang Feng ◽  
Yuandeng Shen ◽  
Zhanjun Tian ◽  
Guoqing Zhao ◽  
...  
Keyword(s):  
Oscillation Period ◽  
Frequency Drift ◽  
Coronal Loops ◽  
Transformation Mechanism ◽  
Density Evolution ◽  
Analytic Dependence ◽  
The Past ◽  
New Energy ◽  
Energy Processes ◽  
Magnetic Plasma

Abstract Although the fast kink oscillation, as one of a few fundamental modes in coronal seismology, has received a lot of attention over the past two decades, observations of its frequency drift remain elusive. There is evidence that this phenomenon is related to the quasi-static evolution of loop density. We therefore consider analytically the effects of a quasi-static density evolution on the fast kink oscillation of coronal loops. From the analyses, we determine explicitly the analytic dependence of the oscillation period/frequency and amplitude on the evolving density of the oscillatory loop. The findings can well reconcile several key characters in some frequency drift observations, which are not understood. Models of fast kink oscillation in the thermal dynamic loop are also established to investigate the present effects in more detail. Our findings not only show us a possible explanation for the frequency drift of the coronal loop’s fast kink oscillation, but also a full new energy transformation mechanism where the internal energy and the kinetic energy of an oscillating coronal loop can be interchanged directly by the interaction of the loop’s oscillation and its density evolution, which we suggest may provide a new clue for the energy processes associated with a thermodynamic resonator in the space magnetic plasma.

China's war against air pollution moves to next stage

2018 ◽  
Keyword(s):  
Air Pollution ◽  
Action Plan ◽  
Industrial Upgrading ◽  
Content Type ◽  
Electric Cars ◽  
The Past ◽  
New Energy ◽  
Mitigate Climate Change ◽  
Energy Intensive Industries ◽  
New Energy Vehicles

Subject China's anti-pollution plans for the next three years. Significance China’s 2018-20 'Three-year Action Plan for Winning the Blue Sky War' is an effort to further decarbonise the economy, with a focus on reducing air pollution. It sees the geographical widening of successful efforts in the past three years, if not a marked increase in ambition, to improve air quality by industrial upgrading, controlling the expansion of polluting industries, supporting new energy vehicles and increasing top-down inspections. Impacts Further closures and other policies will limit the expansion of commodities mined or processed in China, mainly coal, steel and aluminium. Electric cars will receive subsidies and favourable policies such as licence-plate limits for conventional, petrol-burning vehicles. Reducing polluting and energy-intensive industries to reduce smog also reduces carbon emissions, helping to mitigate climate change.

Measurement and Analysis on Energy Efficiency of Elevators in Shanghai

2014 ◽  
Author(s):  
Wu Hao ◽  
Chang Xiaoqing ◽  
Xue Jiai
Keyword(s):  
Energy Efficiency ◽  
Influence Factors ◽  
Electricity Consumption ◽  
Classification Method ◽  
The Past ◽  
Measurement And Analysis ◽  
The World ◽  
New Energy ◽  
Policy Measures ◽  
Research Objects

Shanghai is the largest city of elevators in the world with 165000 elevators and escalators. According to latest research, elevators typically account for about 3% to 8% of the overall electricity consumption of a building. Therefore, it is significantly to study the energy efficiency of elevators in Shanghai. However, elevators have received little attention from an efficiency perspective in the past. To recover this gap, this paper analyses classification method on energy efficiency of elevators in Shanghai and suggests policy measures for energy conservation. First, Representative elevators in Shanghai were collected as research objects; second, a new energy efficiency classification method was established on the modification of VDI4707 according to actual situations in China, then, energy consumption of these elevators were measured and classified according to the new method. Finally, the influence factors of elevator energy efficiency were studied, and suggestion on the improvement of the energy efficiency of elevators in Shanghai was given.

scholarly journals Study on Sustainable Development of China’s New Energy Industry under the Background of Carbon Neutrality

2021 ◽  
Vol 248 ◽  
pp. 02021
Author(s):  
Jian Yuan ◽  
Yuxing An
Keyword(s):  
Sustainable Development ◽  
Rapid Development ◽  
Energy Industry ◽  
Energy Prices ◽  
Absorption Mechanism ◽  
The Sustainable Development ◽  
Carbon Neutrality ◽  
The Past ◽  
New Energy ◽  
Natural Gas Prices

The latest McKenzie Global Energy Outlook predicts that by 2030, new energy prices will be lower than existing coal and natural gas prices in most regions; by 2035, new energy sources (solar energy and wind energy) will account for more than 50% of the world’s electricity generation. The global new energy industry will continue to accelerate in the future after years of its rapid development. Compared to the past, China’s new energy industry has become an important industry leader instead of industry followers a decade ago. However, under the past achievements and carbon neutral constraints, China’s new energy industry still needs to be strengthened and completed in the policies and regulations, absorption mechanism, technical research and development to promote the sustainable development of China’s new energy industry.

scholarly journals RES Implementation in Urban Areas: An Updated Overview

2020 ◽  
Vol 12 (1) ◽  
pp. 382 ◽  
Author(s):  
Ilaria Delponte ◽  
Corrado Schenone
Keyword(s):  
Urban Areas ◽  
Infrastructure Investment ◽  
Energy Planning ◽  
Environmental Damage ◽  
Energy Structure ◽  
The Past ◽  
Time Period ◽  
New Energy ◽  
Critical Issues

In the past, national energy planning guided the development of a central program for infrastructure investment over a defined time period. However, in the current geopolitical context, environmental damage, fossil fuel depletion, and territorial imbalance caused by the centralised energy model are all factors that require a change of energy structure, establishing actions to invest in energy diversification, and solid commitment to local renewable energies. This also implies an enhancement of the role played by local bodies, and particularly by municipalities, in achieving the targets of the Kyoto Protocol and now of the Paris Agreement, because renewable sources need to be studied, applied, and exploited at the local scale. Within this framework, this paper is organized as an overview on the promotion and implementation of the major RES technologies in the deployment of the new energy paradigm at the urban scale, taking into account multiple targets. A survey of existing literature underlines how the RES topic is mostly approached as a problem of energy supply and implementation of technology, but actual sustainability in terms of a social development process and improvement of quality of life by residents is often neglected. Then, this overview stimulated the authors to highlight three main critical issues and gaps and support the need of an all-encompassing approach as a final recommendation for a general RES urban planning advancement.

LIMITS FROM LEP 2 ON POSSIBLE ENHANCEMENT OF Re ∊′/∊ DUE TO ANOMALOUS GAUGE BOSON COUPLINGS

2001 ◽  
Vol 16 (supp01b) ◽  
pp. 669-671
Author(s):  
FRANCESCO TERRANOVA
Keyword(s):  
Standard Model ◽  
Low Energy ◽  
Hadron Colliders ◽  
Anomalous Couplings ◽  
The Past ◽  
The Poor ◽  
The Standard Model ◽  
Energy Processes ◽  
The Impact ◽  
Gauge Boson Couplings

It has been shown in the past that the real part of the ∊′/∊ ratio is particularly sensitive to anomalous gauge couplings that modify the Standard Model Lagrangian. Due to the loose bounds on these couplings coming from low energy processes and to the poor sensitivity of hadron colliders to couplings such as [Formula: see text], it has been argued that anomalous couplings could still produce an enhancement of Re ∊′/∊ bringing this observable closer to the experimental value obtained by KTeV, NA31 and NA48. The impact of the new measurements done at LEP2 in these years is discussed and new severe constraints to this hypothesis are determined.

Introduction

Geophysics ◽  
1978 ◽  
Vol 43 (7) ◽  
pp. 1449-1449
Author(s):  
George V. Keller
Keyword(s):  
Geothermal Energy ◽  
Hot Springs ◽  
Energy Sources ◽  
Geothermal Systems ◽  
Early Start ◽  
The Past ◽  
New Energy ◽  
The Geysers ◽  
Surface Manifestation ◽  
The U.S

The first exploration for geothermal energy in the U.S. apparently took place during the early 1920s in California and at Yellowstone Park in Wyoming. Despite this early start, by the 1950s, commercially developable geothermal steam had been identified only at one location, The Geysers in California. In the past 10 years, interest in developing geothermal energy has advanced rapidly. Many tens of wildcat wells have been drilled in the search for new energy sources. Many more tens of geothermal prospects are being evaluated. This evaluation of new prospects is beginning to have an impact on the science of geophysical exploration. Some geothermal reservoirs can be located merely by drilling close to thermal manifestations such as geysers and fumiroles. In many other cases, leakage of water in hot springs is far removed from the reservoir in which the hot fluids are present, and it is conceivable that many geothermal systems may exist without any surface manifestation. Development of these more or less hidden geothermal systems will require the services of geologists, geochemists, and geophysicists.

Considerations on a Validation Matrix for System Analysis Codes of Pebble Bed Modular HTRs

2017 ◽  
Author(s):  
Feng Gou ◽  
Fubing Chen ◽  
Yujie Dong
Keyword(s):  
System Analysis ◽  
Normal Operation ◽  
Energy Technology ◽  
Pebble Bed ◽  
The Past ◽  
Safety Regulations ◽  
New Energy ◽  
The Subject ◽  
High Temperature Reactor ◽  
Accident Conditions

The modular High Temperature Reactor (HTR) experienced substantial development over the past two decades in China. At present, the 10 MWth experimental reactor HTR-10 is under operation and the 200 MWe demonstration power plant HTR-PM is in its commissioning phase. Both of the HTR-10 and the HTR-PM are pebble bed HTRs designed by the institute of nuclear and new energy technology (INET) of Tsinghua University. In the design and analysis of modular HTRs, system analysis codes play an important role in predicting the reactor behaviour under both normal operation and accident conditions. According to China’s nuclear safety regulations, codes and models employed in the HTR system analysis must be verified and validated in conformance with a specified procedure. Thus, a flowchart is recommended in this paper for the validation of system analysis codes. As the first step of the flowchart, a phenomena identification and ranking table (PIRT) process has been performed on the subject of the HTR-PM thermal hydraulics and accident analysis. In this paper, the PIRT process is introduced and the PIRT results are presented. With the purpose of developing a validation matrix, test data have been collected mainly from the operation history and various tests of the HTR-10. On such basis, some considerations on developing a validation matrix are discussed to benefit the code validation work.

MoteIST

2013 ◽  
Vol 4 (3) ◽  
pp. 82-101 ◽  
Author(s):  
José M. Catela ◽  
Rui M. Rocha ◽  
Moisés S. Piedade
Keyword(s):  
Energy Management ◽  
Energy Efficient ◽  
Modular Architecture ◽  
The Past ◽  
Power Profile ◽  
Energy Efficient Communication ◽  
Efficient Communication ◽  
Memory Footprint ◽  
New Energy ◽  
Management Issues

Architectures for Wireless Sensor Networks platforms have not evolved as expected during the past decade. The monolithic principles of the first nodes are still followed in the new designs. The architectures are not prepared to include upgrades such as new energy management modules or even more energy efficient communication units. This leads to constraints on the development of new protocols and applications, since the software takes the entire burden on the reconfigurability and optimization that could be done by a modular architecture. In this work, the authors propose a new platform - MoteIST - with a different architecture, introducing higher modularity and addressing the energy management issues, while maintaining the compatibility with previously designed software and sensing boards. The authors’ design enables different energy management solutions, including harvesting modules and different communication units, such as wake-up, sub-1 GHz and 2.4 GHz radios. The authors describe the implementation and analyze the relevant characteristics of MoteIST, namely its memory footprint and power profile.

Study on Hydraulic Fracturing Affected by Natural Fractures

2014 ◽  
Vol 501-504 ◽  
pp. 2056-2059
Author(s):  
Jian Qiu Sun ◽  
Tian Hui Ma ◽  
Liao Yuan Zhang ◽  
Bo Huang ◽  
Ai Shan Li
Keyword(s):  
Hydraulic Fracturing ◽  
Shale Gas ◽  
Crack Formation ◽  
Technology Development ◽  
The Past ◽  
Basic Assumptions ◽  
Energy Needs ◽  
New Energy ◽  
Industrial Energy ◽  
Substantial Progress

It could be seen from the past, process of the promoting progress of human society's tends to demanding for energy.With the advancement of technology development as time goes on, countries spare no effort to develop new energy sources, while also continue digging traditional industrial energy. Since the 1960`s, people in the field of shale gas exploitation has made substantial progress. For the development of new energy storage proposed higher requirements, in order to meet growing energy needs, for geotechnical engineering particularity, from the numerical simulation of hydraulic fracturing start by comparing different stress crack formation in case of carry case, at the conclusion on the basis of experimental results can be applied to specific projects put forward the basic assumptions.

scholarly journals Significance of Cooling Effect on Comprehension of Kink Oscillations of Coronal Loops

2021 ◽  
Vol 7 ◽  
Author(s):  
Daria Shukhobodskaia ◽  
Alexander A. Shukhobodskiy ◽  
Chris J. Nelson ◽  
Michael S. Ruderman ◽  
Robert Erdélyi
Keyword(s):  
Coronal Loop ◽  
Thermal Evolution ◽  
Oscillation Amplitude ◽  
Density Ratio ◽  
Resonant Absorption ◽  
Coronal Loops ◽  
The Past ◽  
Kink Mode ◽  
Mode Oscillation ◽  
Complex Damping

Kink oscillations of coronal loops have been widely studied, both observationally and theoretically, over the past few decades. It has been shown that the majority of observed driven coronal loop oscillations appear to damp with either exponential or Gaussian profiles and a range of mechanisms have been proposed to account for this. However, some driven oscillations seem to evolve in manners which cannot be modeled with purely Gaussian or exponential profiles, with amplification of oscillations even being observed on occasions. Recent research has shown that incorporating the combined effects of coronal loop expansion, resonant absorption, and cooling can cause significant deviations from Gaussian and exponential profiles in damping profiles, potentially explaining increases in oscillation amplitude through time in some cases. In this article, we analyze 10 driven kink oscillations in coronal loops to further investigate the ability of expansion and cooling to explain complex damping profiles. Our results do not rely on fitting a periodicity to the oscillations meaning complexities in both temporal (period changes) and spatial (amplitude changes) can be accounted for in an elegant and simple way. Furthermore, this approach could also allow us to infer some important diagnostic information (such as, for example, the density ratio at the loop foot-points) from the oscillation profile alone, without detailed measurements of the loop and without complex numerical methods. Our results imply the existence of correlations between the density ratio at the loop foot-points and the amplitudes and periods of the oscillations. Finally, we compare our results to previous models, namely purely Gaussian and purely exponential damping profiles, through the calculation of χ2 values, finding the inclusion of cooling can produce better fits in some cases. The current study indicates that thermal evolution should be included in kink-mode oscillation models in the future to help us to better understand oscillations that are not purely Gaussian or exponential.

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