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Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Rural Water & Hydropower is the property of China Rural Water & Hydropower Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Field aligned currents (FACs), also known as Birkland current, are flowing along the magnetic field line between the ionosphere and magnetosphere. They play an essential role in transferring mass, energy, and momentum from the magnetosphere to the ionosphere at high latitudes. FACs arouse much interest in magnetospheric and ionospheric physics even about 60 years after their first experimental discovery. Many critical physical processes in the geospace (e.g., aurora, geomagnetic storm, substorm et al.) are believed to be related to FACs. Scientists have performed a lot of researches on FACs' characteristics and generation mechanisms using ground and space observations. This paper reviews different types of large-scale ionospheric FACs and their temporal and spatial distribution during active geomagnetic conditions (magnetic storm and substorm). Firstly, the paper briefly reviews how the term of FACs were proposed and the related historical disputes. With the launch of the manufactured satellites and the advent of the space age, the in situ observation of magnetic fields from low Earth orbit satellite provides direct evidence for FACs. The paper summarizes the characteristics of traditional region 1 and region 2 FACs (R1, R2), northward interplanetary magnetic field (IMF, NBZ) and IMF By (DPY) FACs, newly discovered IMF Bx FACs, and ionospheric terminal FACs. FACs are related to the divergence of the magnetospheric currents and magnetospheric electric field. The ionosphere acts as a load in the current circuit. We review the research process on the characteristics of the magnetospheric source region of R1 and R2 FACs. The magnetospheric source of FACs exhibits noticeable local time differences. The source of the dayside FACs behaves as a voltage source, while that of the nighttime FACs is like a current source. The paper summarizes the research results on the relative intensity of R1 and R2 FACs under different external conditions. Typically R1 FACs are larger than R2 FACs, but R2 FACs can be larger than R1 FACs under certain external IMF conditions. The dipole tilt angle is revealed to be vital in the transformation process from NBZ to DPY FACs and vice versa. A new type of FACs in the cusp region related to IMF Bx and related effects on the ionosphere and thermosphere is disclosed. In addition to the above currents generated in the magnetosphere, a new type of FACs is revealed related to the ionospheric conductivity gradient in the daytime-nighttime terminal. This paper summarizes the latitudes, polarities and strengths variation of large scale FACs with geomagnetic storm phases. The controlling roles of solar wind and magnetospheric coupling parameters are also discussed. The local time asymmetry of FACs (like the dawn versus dusk sector, daytime versus nighttime) during storm periods and its specific physical mechanisms are summarized. Several different physical modes of substorm FACs are reviewed. The observation and related arguments of single substorm current wedge (SCW) and double SCW are detailed. The shift of the SCW center from midnight to the dawn sector is discussed in the framework of IMF By and ionospheric conductivity. Two SCW systems are coexisting in the pre-midnight and postmidnight sectors. In addition, the relative importance of ionospheric remote and local closed channels of SCW is discussed. Finally, some open scientific questions, such as the small scale FACs, hemispheric and local time asymmetry of FACs during storm and substorm periods, are put forward for future work.

Storm is suffering the problems of high energy consumption but low efficiency.Aiming at this problem,the resource constraint model,the optimal principle of data reorganization in executors and node voltage reduction principle were proposed based on the analysis of the architecture and topology of Storm,and further the energy-efficient strategy for data migration and merging was put forward in Storm(DMM-Storm),which was composed of resource constraint algorithm,data migration and merging algorithm as well as node voltage reduction algorithm.The resource constraint algorithm estimates whether work nodes are appropriate for data migration according to the resource constraint model.The data migration and merging algorithm designs an optimal method to migrate data according to the the optimal principle of data reorganization in executors.The node voltage reduction algorithm reduces voltage of work nodes according to node voltage reduction principle.The experimental results show that the DMM-Storm can reduce energy consumption efficiently without affecting the performance of cluster compared with the existing researches.

Copyright of Journal of Mine Automation is the property of Industry & Mine Automation Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Focused on the problem that traditional energy-efficient strategies never consider about the real time of data processing and transmission,models of directed acyclic graph,parallelism of instance,resource allocation for task and critical path were set up based on the features of data stream processing and the structure of storm cluster.Meanwhile,the WNDVR-storm (energy-efficient strategy for work node by dram voltage regulation in storm) was proposed according to the analysis of critical path and system performance,which included two energy-efficient algorithms aiming at whether there were any work nodes executing on the non-critical path of a topology.Finally,the appropriate threshold values fit for the CPU utilization of work node and the volume of transmitted data were determined based on the data processing and transmission constraints to dynamically regulate the DRAM voltage of the system.The experimental result shows that the strategy can reduce energy consumption effectively.Moreover,the fewer constraints are,the higher energy efficiency is.

Based on the TELEMAC numerical model system, this paper adds soluble pollutants as tracers to the two-dimensional hydrodynamic model, introduces the concept of water residence time, calculates the water residence time in Zhanjiang Bay. The results indicate that the retention time of water in Zhanjiang Bay during flood and dry seasons is 4.9 d and 10.5 d, respectively. In dry season, the runoff of upstream rivers is small, which is not enough to purify and scour the water in the bay, so the residence time is longer. The retention time of water bodies in Zhanjiang Bay during high tide and low tide in dry season were 8.9 d and 9.5 d, respectively. The tidal dynamics during the high tide period is stronger than that during the low tide period, so the water residence time in the study area during the high tide period is shorter, and the pollutants can circulate and dilute in a shorter time. The retention time of water bodies in the Inner Zhanjiang Bay (north of Techeng Island) and Zhanjiang Bay (south of Techeng Island) are 1.3.0 d and 12.0 d in dry season, respectively. The periphery of Zhanjiang Bay is composed of many islands, which have become natural protective barriers and hinder the communication and entry of water bodies. The inner bay is located in the north of Techeng Island and is close to the inland. The shape of the bay is more closed. The seawater flow rate is slow, the pollutant dilution capacity is weak, and the water residence time is long. The residence time of the water body in Zhanjiang Bay under the conditions of storm surge and static wind field is 10.6 d and 12.0 d, respectively. The storm surge speeds up the seawater flow in the entire study area. The average residence time of water bodies in the study area is reduced. The residence time of the water in Zone V (west of the East China Sea Levee) before and after the construction of the levee was 9.5 d and 11.5 d, respectively. The construction of the East China Sea Levee hinders the flow of seawater on both sides of the Levee, especially the west side, making it difficult for pollutants to be diluted in the surrounding waters, and the water residence time in the surrounding waters increases. [ABSTRACT FROM AUTHOR]

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Open-source distributed real-time computing framework Storm in the Internet, finance, E-commerce and other fields has been widely used. By default, Storm uses the polling scheduling policy and relies on the user’s configuration of topology tasks in parallel. When the configuration is unreasonable, Storm still causes delays in topology processing and decreases throughput. To solve this problem, this paper proposed a greedy scheduling algorithm based on best parallelism in Storm. When scheduling,first it solved the best parallelism of each component in topology task,and then adopted greedy policy to minimize the network communication between nodes. Compared with the default scheduling algorithm, the online scheduling algorithm and the hot-side scheduling algorithm, the results show that the algorithm can effectively reduce the Storm processing delay and improve the system throughput and resource utilization. [ABSTRACT FROM AUTHOR]

Big data platform based on the Hadoop structures using offline batch processing mode，unable to meet the service requirements for data timeliness.In order to solve the real-time signal processing requirements in operator OIDD（open information of dynamic data）big data platform，the big-data system components of stream computing were discussed，real-time data collecting，distribution and processing components which formed the end-to-end real-time signal processing big data technology solutions were recommended，and the solutions of the OIDD big data platform which integrated batch computing and stream computing were proposed.It will improve the timeliness of the network signaling data and provide more space for business innovation and bring more benefits.

Copyright of Journal of Agricultural Science & Technology (1008-0864) is the property of Journal of Agricultural Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal on Communication / Tongxin Xuebao is the property of Journal on Communications Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

It discussed the core ideas and programming model of Storm, and analyzed its working mode and application method. Finally, it implemented the performance and horizontal scaling test of a data processing system based on Storm. The experimental results show that the performance and scalability of Storm is superior to that of the traditional data processing system. [ABSTRACT FROM AUTHOR]

With the improvement of the quality of clinical diagnosis and treatment, the traditional scheduled "ward round" mode cannot meet the demands for real-time monitoring of acute and critically ill patients. This paper introduces the Storm, a real-time data stream processing technology and its application in the real time disease early warning system. By collecting the clinical data flow and calculating the MEWS scores in real time, the system can identify the potential deterioration of the disease, and promptly notify the medical staff. Score calculation results can be stored for further analysis and presentation as well.