scholarly journals Active System for Electromagnetic Perturbation Monitoring in Vehicles

2010 ◽  
pp. 409-416 ◽  
Author(s):  
Adrian Marian Matoi ◽  
Elena Helerea
Keyword(s):  
Active System ◽  
Electromagnetic Perturbation

A New User-controlled and Efficient Encrypted Data Sharing Model in Cloud Storage

2019 ◽  
Vol 13 (4) ◽  
pp. 356-363
Author(s):  
Yuezhong Wu ◽  
Wei Chen ◽  
Shuhong Chen ◽  
Guojun Wang ◽  
Changyun Li
Keyword(s):  
Data Sharing ◽  
Data Security ◽  
Cloud Storage ◽  
Screening Program ◽  
Original Data ◽  
Third Party ◽  
Active System ◽  
Encrypted Data ◽  
Active User ◽  
User Data

Background: Cloud storage is generally used to provide on-demand services with sufficient scalability in an efficient network environment, and various encryption algorithms are typically applied to protect the data in the cloud. However, it is non-trivial to obtain the original data after encryption and efficient methods are needed to access the original data. Methods: In this paper, we propose a new user-controlled and efficient encrypted data sharing model in cloud storage. It preprocesses user data to ensure the confidentiality and integrity based on triple encryption scheme of CP-ABE ciphertext access control mechanism and integrity verification. Moreover, it adopts secondary screening program to achieve efficient ciphertext retrieval by using distributed Lucene technology and fine-grained decision tree. In this way, when a trustworthy third party is introduced, the security and reliability of data sharing can be guaranteed. To provide data security and efficient retrieval, we also combine active user with active system. Results: Experimental results show that the proposed model can ensure data security in cloud storage services platform as well as enhance the operational performance of data sharing. Conclusion: The proposed security sharing mechanism works well in an actual cloud storage environment.

Miniaturized all-in-one nanoGIT+active system for on-surface metabolization, separation and effect imaging

2021 ◽  
Vol 1154 ◽  
pp. 338307
Author(s):  
Gertrud E. Morlock ◽  
Lena Drotleff ◽  
Sabrina Brinkmann
Keyword(s):  
Active System

scholarly journals Architectural and functional classification of smart grid solutions

2019 ◽  
Vol 2 (S1) ◽  
Author(s):  
Friederike Wenderoth ◽  
Elisabeth Drayer ◽  
Robert Schmoll ◽  
Michael Niedermeier ◽  
Martin Braun
Keyword(s):  
Smart Grid ◽  
Power Systems ◽  
Power System ◽  
Power Distribution ◽  
Hierarchical Architecture ◽  
Distribution Grid ◽  
Active System ◽  
System Operation ◽  
Power System Operation

Abstract Historically, the power distribution grid was a passive system with limited control capabilities. Due to its increasing digitalization, this paradigm has shifted: the passive architecture of the power system itself, which includes cables, lines, and transformers, is extended by a communication infrastructure to become an active distribution grid. This transformation to an active system results from control capabilities that combine the communication and the physical components of the grid. It aims at optimizing, securing, enhancing, or facilitating the power system operation. The combination of power system, communication, and control capabilities is also referred to as a “smart grid”. A multitude of different architectures exist to realize such integrated systems. They are often labeled with descriptive terms such as “distributed,” “decentralized,” “local,” or “central." However, the actual meaning of these terms varies considerably within the research community.This paper illustrates the conflicting uses of prominent classification terms for the description of smart grid architectures. One source of this inconsistency is that the development of such interconnected systems is not only in the hands of classic power engineering but requires input from neighboring research disciplines such as control theory and automation, information and telecommunication technology, and electronics. This impedes a clear classification of smart grid solutions. Furthermore, this paper proposes a set of well-defined operation architectures specialized for use in power systems. Based on these architectures, this paper defines clear classifiers for the assessment of smart grid solutions. This allows the structural classification and comparison between different smart grid solutions and promotes a mutual understanding between the research disciplines. This paper presents revised parts of Chapters 4.2 and 5.2 of the dissertation of Drayer (Resilient Operation of Distribution Grids with Distributed-Hierarchical Architecture. Energy Management and Power System Operation, vol. 6, 2018).

A Study of Control Strategy for Vehicle Semi-Active Suspension System

1991 ◽  
Author(s):  
Yiming Zhang ◽  
Ye Lin
Keyword(s):  
Optimal Control ◽  
Control Strategy ◽  
Active Suspension ◽  
Suspension System ◽  
Statistical Characteristics ◽  
Active System ◽  
Optimal Control Strategy ◽  
Performance Limit ◽  
Passive Suspension ◽  
Isolation Performance

Abstract This paper investigates a reference control strategy for Vehicle semi-active suspension. The control is conducted by following the idea optimal active controller. The passive actuator is set to optimal whenever the active and passive actuators have the same signs; and set to zero output whenever the two signs are opposite. The simulation results of a 2DoF vehicle show that the semi -active suspension system can follow the ideal active system very well, both are superior to conventional passive systems. In this paper, a 2DoF vehicle model was also used to study a statistical optimal control strategy of the semi-active suspension system. The statistical optimal concept is the result of the combination of the nonlinear programming and controllable damper. A way of estimating statistical characteristics of road irregularities was also proposed. Vehicle active, suspension, due to its perfect v i bra t i on isolation performance, gets moreand more attention. Active suspension can be generally divided into two categories, totally active suspension system and semi-active suspension system. From the published results it is known that active suspension can surpass the performance limit of conventional passive suspension and greatly improve the vehicle riding comfort and steering ability. But active suspension has a critical disadvantage of less applicability, due to its high cost and low reliability. Also it consumes large amount of energy as it works. The idea of semi-active suspension was put forward to overcome the shortcoming of active suspension. It is a compromise between active suspension and passive suspension. Semi-active suspension has approximately the same behavior as active suspension, and almost consumes no energy as it works. So semi-active suspension possesses a great potential in application. At. present, in the field of suspension research over the world, a great deal of attention is paied to semi-active suspension. At present, for the cotrol of semi-active suspension the widely studied strategy is “on off” control [1] [2], which is first put forward by Karnopp. “On-off” control can eliminate the phenomenon of vibration amplification for passive suspension, thus it can improve the suspension performance to certain extent. At present, no substantive result has been obtained yet in the field of optimal control of semi-active suspension. This paper will investigate a reference control strategy on the basis of linear optimal control. The control is conducted by following the optimal ctive controller. The referrence control result is optimal when the outputs of the active and semi-active force generators have the same signs.

OXIDATION-REDUCTION POTENTIALS IN CULTURES OF ES. COLI

1931 ◽  
Vol 4 (6) ◽  
pp. 605-613 ◽  
Author(s):  
Eldon M. Boyd ◽  
Guilford B. Reed
Keyword(s):  
Growth Period ◽  
Active System ◽  
Reduction Potentials ◽  
Oxidation Reduction ◽  
Logarithmic Growth

Following the evidences advanced in a previous paper that metabolic gases are concerned in the production of growth-oxidation-reduction potentials observed in cultures of bacteria, experiments have been arranged to test the effects of such gases in comparison with other factors. Growth and oxidation-reduction potentials have been determined simultaneously in anaërobic buffered broth cultures of Es. coli. It is shown that in sugar-free broth there is a sudden fall in potential at the beginning of the logarithmic growth period. The addition of glucose to the medium was found to induce an earlier and more precipitous fall in potential which is coincident with the first evolution of gas. At the same time there was found to be evidence of a non-gaseous electromotively active system in these cultures.

scholarly journals Implementation of a Piezo-diagnostics Approach for Damage Detection Based on PCA in a Linux-Based Embedded Platform

Sensors ◽  
2018 ◽  
Vol 18 (11) ◽  
pp. 3730 ◽  
Author(s):  
Jhonatan Camacho ◽  
Andrés Quintero ◽  
Magda Ruiz ◽  
Rodolfo Villamizar ◽  
Luis Mujica
Keyword(s):  
Statistical Model ◽  
Damage Detection ◽  
Structural Integrity ◽  
Statistical Processing ◽  
Principal Component ◽  
Detection Methods ◽  
Active System ◽  
Pipe Surface ◽  
Wave Response ◽  
Piezoelectric Devices

The implementation of damage-detection methods for continuously assessing structural integrity entails systems with attractive features such as storage capabilities, memory capacity, computational complexity and time-consuming processing. In this sense, embedded hardware platforms are a promising technology for developing integrated solutions in Structural Health Monitoring. In this paper, design, test, and specifications for a standalone inspection prototype are presented, which take advantage of piezo-diagnostics principle, statistical processing via Principal Component Analysis (PCA) and embedded systems. The equipment corresponds to a piezoelectric active system with the capability to detect defects in structures, by using a PCA-based algorithm embedded in the Odroid-U3 ARM Linux platform. The operation of the equipment consists of applying, at one side of the structure, wide guided waves by means of piezoelectric devices operated in actuation mode and to record the wave response in another side of the structure by using the same kind of piezoelectric devices operated in sensor mode. Based on the nominal response of the guide wave (no damages), represented by means of a PCA statistical model, the system can detect damages between the actuated/sensed points through squared prediction error (Q-statistical index). The system performance was evaluated in a pipe test bench where two kinds of damages were studied: first, a mass is added to the pipe surface, and then leaks are provoked to the pipe structure by means of a drill tool. The experiments were conducted on two lab structures: (i) a meter carbon-steel pipe section and (ii) a pipe loop structure. The wave response was recorded between the instrumented points for two conditions: (i) The pipe in nominal conditions, where several repetitions will be applied to build the nominal statistical model and (ii) when damage is caused to the pipe (mass adding or leak). Damage conditions were graphically recognized through the Q-statistic chart. Thus, the feasibility to implement an automated real-time diagnostic system is demonstrated with minimum processing resources and hardware flexibility.

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