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121.
One of the main objectives of synthetic biology is the development of molecular controllers that can manipulate the dynamics of a given biochemical network that is at most partially known. When integrated into smaller compartments, such as living or synthetic cells, controllers have to be calibrated to factor in the intrinsic noise. In this context, biochemical controllers put forward in the literature have focused on manipulating the mean (first moment) and reducing the variance (second moment) of the target molecular species. However, many critical biochemical processes are realized via higher-order moments, particularly the number and configuration of the probability distribution modes (maxima). To bridge the gap, we put forward the stochastic morpher controller that can, under suitable timescale separations, morph the probability distribution of the target molecular species into a predefined form. The morphing can be performed at a lower-resolution, allowing one to achieve desired multi-modality/multi-stability, and at a higher-resolution, allowing one to achieve arbitrary probability distributions. Properties of the controller, such as robustness and convergence, are rigorously established, and demonstrated on various examples. Also proposed is a blueprint for an experimental implementation of stochastic morpher.  相似文献   
122.
Recent times have witnessed a significant positive trend in adoption of renewable energy sources and DC-based loads, which questions the efficiency and reliability of existing structure of electrical power system. DC microgrids are identified as potential solutions for addressing India's and other developing nations' rural electrification. This paper presents an energy management technique for isolated DC microgrids for academic readers, as well as provides an introduction to not-familiarized readers for understanding the common design challenges for implementing off-grid power systems. The principle of the proposed technique is based on law of energy conservation defined by the energy balance equation and is implemented by synthesizing the instantaneous current reference and hysteresis control with source priority, which was validated by rigors simulation studies in Matlab/Simulink. Furthermore, in order to demonstrate the modularity and scalability of the algorithm, it was tested on a prototype hardware test setup at the Solar Energy Research Centre, VIT University.  相似文献   
123.
This paper presents a new method of non-active power compensation in power systems under non-sinusoidal conditions. The basic idea of the compensation procedure stems from the condition for the minimum rms value of line currents. The application of optimization procedure, observing the above criterion, results in the required compensator. Three different compensators are derived: total non-active power compensator, compensator without energy storage, and reactive compensator. The paper introduces the factors which define the amount of active power in total power before and after the non-active power compensation. The compensation procedure is valid for single-phase and polyphase systems. Simulation results confirm the validity and applicability of the compensation procedure for a diversity of load currents.  相似文献   
124.
Lipids play an essential role in both tissue protection and damage. Tissue ischemia creates anaerobic conditions in which enzyme inactivation occurs, and reperfusion can initiate oxidative stress that leads to harmful changes in membrane lipids, the formation of aldehydes, and chain damage until cell death. The critical event in such a series of harmful events in the cell is the unwanted accumulation of fatty acids that leads to lipotoxicity. Lipid analysis provides additional insight into the pathogenesis of ischemia/reperfusion (I/R) disorders and reveals new targets for drug action. The profile of changes in the composition of fatty acids in the cell, as well as the time course of these changes, indicate both the mechanism of damage and new therapeutic possibilities. A therapeutic approach to reperfusion lipotoxicity involves attenuation of fatty acids overload, i.e., their transport to adipose tissue and/or inhibition of the adverse effects of fatty acids on cell damage and death. The latter option involves using PPAR agonists and drugs that modulate the transport of fatty acids via carnitine into the interior of the mitochondria or the redirection of long-chain fatty acids to peroxisomes.  相似文献   
125.
Poly(aniline-co-(m-aminobenzoic acid)) was synthesized electrochemically at graphite electrode under galvanostatic conditions. Aqueous electrolyte for synthesis was consisted of HCl and different amount of aniline and m-aminobenzoic acid. The presence of the meta positioned carboxylic group in m-aminobenzoic acid influenced higher co-polymerization potential, different morphology and electrochemical behavior of copolymers compared to polyaniline. Electrochemical activity is achieved by proton exchange in neutral environment that can result in a faster charge/discharge process, which is in the case of PANI limited by slow anion exchange, making this material promising for consideration in super-capacitors and in biological system.  相似文献   
126.
There are various methods for procurement of reactive power as an ancillary service in deregulated market environment. Reactive power market model based on voltage control zones and two-step optimal power flow algorithm is proposed in this paper. Zones are formed by splitting the power system or a control area of an interconnected power system into autonomous voltage sub-areas with sufficient reactive power reserves using the electrical distance method. Every zone formes a single reactive power market. First step of an optimization algorithm determines zonal reactive power prices based on generator's cost functions for reactive power production. Total cost minimization is the goal of the second optimization step where the final dispatching decision is made according to transmission losses and zonal reactive power prices respecting power system planned conditions and security constraints. Proposed algorithm is tested on IEEE 39 bus test system ensuring the system operator's minimal payment for reactive power and transmission losses, without jeopardizing power system security.  相似文献   
127.
The fuzzy logic‐based approach was applied in studying the influence of a different textile surface structure on colour appearance and similarity. The fuzzy‐based approach has been chosen because fuzzy logic provides the computerising of human reasoning. For the analyses, 100% cotton samples with certain characteristics were chosen. First, the computer match prediction was performed to determine the concentrations of dyestuff to be used in the experimental work. A yellow‐shaded direct dyestuff suitable for cotton dyeing was used. In the next step, the fuzzy logic system was created based on terms that would define the surface characteristics of the samples. The most important part was a proper definition of the rules and linguistic variables that use words for assigning the values of properties and that influence the experience of an observer (gloss, smoothness, roughness, etc.) and connect input space with output space. Finally, the performances of both systems were compared and analysed. In this work, the approach was based solely on the surface–structural characteristics of textile samples. The main aim was to examine the approach using the fuzzy logic‐based technique in order to provide the method that would include surface parameters of textile samples that are of importance in applying colour to different structured textile surfaces. It was confirmed that the fuzzy logic reasoning would have its application in the control of the influence of the surface structure of coloured textiles, especially for lighter shades where the influence of structure parameters on the colour experience of an observer is more emphasised.  相似文献   
128.
As a continuing effort of expanding the scope of catalyst regeneration in the presence of environmentally benign reducing agents, one-pot sequential azide–alkyne [3+2] cycloaddition and atom transfer radical addition (ATRA) reactions were performed via in situ reduction of copper(II) by ascorbic acid. The formation of functionalized triazoles was achieved utilizing a ligand-free catalytic system for the cycloaddition between tripropargylamine and vinylbenzyl azide and subsequent addition of tris(2-pyridyl)methylamine (TPMA) ligand in the ATRA step. With this strategy, reactions with carbon tetrachloride and carbon tetrabromide proceeded efficiently providing the desired triazoles in nearly quantitative yields (>90 %) using 10 mol % of copper. Sequential azide–alkyne [3+2] cycloaddition and ATRA reactions were also extended to less active alkyl halides such as methyl trichloroacetate, methyl dichloroacetate and dichloroacetonitrile. The corresponding products were obtained in modest yields (50–80 %). The presented methodology enables efficient synthesis of functionalized polytriazoles, which could have a potential use as chelating agents for a variety of transition metals.  相似文献   
129.
In this paper, we present the model and simulator of a multi-agent system (MAS) for temporally rich domains. The theoretical foundations of the model include a knowledge representation scheme based on an original modification of Petri nets, called Petri nets with time tokens (PNTTs), as well as temporal reasoning based on the extension of Allen's temporal logic. The proposed MAS, called TeMAS, has a hierarchical structure, consisting of different levels, where each level contains clusters of agents. A paradigm of hierarchically organized blackboards is used for the communication among agents, clusters, as well as levels. We describe an object-oriented implementation of a program simulator of TeMAS and give an example of the use of the simulator for interpretation of events in a dynamic scene. Slobodan Ribarić received the B.S. degree in electronics, the M.S. degree in automatics, and the Ph.D. degree in electrical engineering from the Faculty of Electrical Engineering, Ljubljana, Slovenia, in 1974, 1976, and 1982, respectively. He is currently a Full Professor at the Department of Electronics, Microelectronics, Computer and Intelligent Systems, Faculty of Electrical Engineering and Computing, University of Zagreb, Croatia. His research interests include pattern recognition, artificial intelligence, biometrics, computer architecture and robot vision. He has published more than 150 papers on these topics and authored four books (Microprocessor Architecture, The Fifth Computer Generation Architecture, Advanced Microprocessor Architectures, CISC and RISC Computer Architecture) and co-authored one book (An Introduction to Pattern Recognition). Dr. Ribarić is a Member of the IEEE, ISAI and IAPR. Tomislav Hrkać received the B.S. degree in computer science from the Faculty of Electrical Engineering and Computing at the University of Zagreb, Croatia, in 1999. Since October 2000, he has been a Researcher with the Department of Electronics, Microelectronics, Computer and Intelligent Systems at the same faculty. He received the M.S. degree in 2004. As a co-author, he published several papers in international conference proceedings and a paper in a reviewed scientific journal. He is a Student Member of IEEE.  相似文献   
130.
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