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Multi-energy industrial parks, composed of the district energy supply system and terminal industrial loads, are dominant energy consumers with over 50% occupation of total energy consumption. Considering the energy conversion in the district energy supply system and adjustment of production subtasks in terminal industrial loads, the industrial parks could provide considerable flexibility for utility multi-energy systems to deal with contingencies. However, industrial parks may have multiple uncertainties originating from the production subtasks' variability, distributed renewable energy's fluctuation, and random failures of equipment. These uncertainties could make the flexibility assessment of industrial parks unreliable, which may further exacerbate utility system risks. To address the problem, this paper innovatively proposes the concept of probabilistic integrated flexible regions and corresponding characterization approaches, which can effectively describe the credible multi-energy adjustment ability of industrial parks. First, the energy-material flows in the industrial park are modeled considering multiple uncertainties while subject to constraints such as operating limits of equipment, energy and material balancing, and production targets. Then, the modeling and calculation methods of probabilistic integrated flexible regions are given. These regions are labeled with certain probability requirements and visualized in the input multi-energy space. Using a real-world test system that produces air conditioning equipment in China, the results show that the proposed model can effectively reflect the probability characteristics of the integrated flexibility under multiple uncertainties. For this test system, the area of a highly credible integrated flexibility, represented by the probabilistic integrated flexible region with 99% probability, is about half of that obtained by the deterministic model. That is, half of the integrated flexibility evaluated by the dete

Разработана тест-система для опредеения афлатоксина В1 методом ИФА. Отработанная методика синтеза иммуноферментного конъюгата афлотоксин-ЩФ и подобраны стабилизирующие растворы для его хранения для создания иммуноферментной тест-системы. Подобран стабилизирующий раствор для хранения конъюгата и раствор на основе трисового буфера, который лучше справлялся с преодолением неспецифических взаимодействий антител с материалом планшета и уменьшал количество ложных результатов при постановке анализа. Для определения чувствительности разработанной ИФА тест-системы готовили серию разведений стандарта афлатоксина В1 в молоке с концентрациями 0, 1, 5, 10, 20, 40, 80, 160, 320, 640 ppb. Образцы тестировали методом ИФА и с помощью ВЭЖХ. Определено, что чувствительность обнаружения афлатоксина В1 в разработаной тест-системе ИФА (ELISA) составляет 4-40 ppb, а в ВЭЖХ 1-320 ppb. Доказано, что хроматографические методы (тонкослойной хроматографии и ВЭЖХ) менее специфичны по сравнению с иммуноферментным анализом. Получив основные компоненты тест-системы и оптимизировав условия проведения анализа показано, что разработанная тест-система легко воспроизводима, имеет высокую чувствительность и специфичность., The test system was developed for the detection of aflatoxin B1 by ELISA. The methodology for synthesis of immune-enzyme aflatoxin-alkaline phosphatase conjugates was completed and selected stabilizing solutions for the storage and creating ELISA test system. The stabilizing solution was selected for storing conjugate and trises buffer solution that better cope with overcoming nonspecific interactions of antibodies with the material of plate and reduces amount of false positives in the formulation of analysis. For determining the sensitivity of developed ELISA test systems was prepared the dilutions series of aflatoxin B1 standards in milk at the concentrations 0, 1, 5, 10, 20, 40, 80, 160, 320, 640 ppb. The samples were analized by ELISA and HPLC. Determined that the sensitivity of detection of aflatoxin B1 at the developed of ELISA test system is 4-40 ppb, and HPLC 1-320 ppb. Was proved that the chromatographic techniques (thin layer chromatography and HPLC) compared with the ELISA less specific. After receiving the basic components of the test system and optimized of the analysis conditions were showed that the developed test system can be easily reproducible and has a high sensitivity and specificity.

This paper proposes a new HVDC grid test system for electro-magnetic transient analysis, suitable for HVDC power system studies ranging from protection to dynamic studies investigating converter behaviour and interactions. In the recent past research interest in HVDC grids has increased, leading to a multitude of studies concerning dc power flow and optimal power flow, dynamics and HVDC grid protection. However, each of these studies makes use of different grid topologies, configurations and transmission line parameters. In this paper, a standard HVDC grid test system is proposed and an implementation in EMT-type software is provided. The implementation in EMT-type software makes use of a frequency dependent cable model, continuous converter model and a reduced dc breaker model. By means of a protection study, the effectiveness and computational efficiency of the proposed HVDC grid test system is demonstrated. The model with its parameters will be made publicly available., QC 20151211

Trajectory sensitivity analysis (TSA) is used as a tool for suitable placement of multiple series compensators in the power system. The goal is to maximize the benefit of these devices in order to enhance the transient stability of the system. For this purpose, the trajectory sensitivities of the rotor angles of the most critical generators with respect to the reactances of transmission lines are calculated in the presence of the most severe faults. Based on the obtained trajectory sensitivities, a method is proposed to determine how effective the series compensation of each transmission line is for improving the transient stability. This method is applied to the Nordic-32 test system to find the priorities of the transmission lines for installation of several series compensators. Simulation with industrial software shows the validity and efficiency of the proposed method., QC 20140123

Trajectory sensitivity analysis (TSA) is used as a tool for suitable placement of multiple series compensators in the power system. The goal is to maximize the benefit of these devices in order to enhance the transient stability of the system. For this purpose, the trajectory sensitivities of the rotor angles of the most critical generators with respect to the reactances of transmission lines are calculated in the presence of the most severe faults. Based on the obtained trajectory sensitivities, a method is proposed to determine how effective the series compensation of each transmission line is for improving the transient stability. This method is applied to the Nordic-32 test system to find the priorities of the transmission lines for installation of several series compensators. Simulation with industrial software shows the validity and efficiency of the proposed method., QC 20140123

Trajectory sensitivity analysis (TSA) is used as a tool for suitable placement of multiple series compensators in the power system. The goal is to maximize the benefit of these devices in order to enhance the transient stability of the system. For this purpose, the trajectory sensitivities of the rotor angles of the most critical generators with respect to the reactances of transmission lines are calculated in the presence of the most severe faults. Based on the obtained trajectory sensitivities, a method is proposed to determine how effective the series compensation of each transmission line is for improving the transient stability. This method is applied to the Nordic-32 test system to find the priorities of the transmission lines for installation of several series compensators. Simulation with industrial software shows the validity and efficiency of the proposed method., QC 20140123

Trajectory sensitivity analysis (TSA) is used as a tool for suitable placement of multiple series compensators in the power system. The goal is to maximize the benefit of these devices in order to enhance the transient stability of the system. For this purpose, the trajectory sensitivities of the rotor angles of the most critical generators with respect to the reactances of transmission lines are calculated in the presence of the most severe faults. Based on the obtained trajectory sensitivities, a method is proposed to determine how effective the series compensation of each transmission line is for improving the transient stability. This method is applied to the Nordic-32 test system to find the priorities of the transmission lines for installation of several series compensators. Simulation with industrial software shows the validity and efficiency of the proposed method., QC 20140123

Trajectory sensitivity analysis (TSA) is used as a tool for suitable placement of multiple series compensators in the power system. The goal is to maximize the benefit of these devices in order to enhance the transient stability of the system. For this purpose, the trajectory sensitivities of the rotor angles of the most critical generators with respect to the reactances of transmission lines are calculated in the presence of the most severe faults. Based on the obtained trajectory sensitivities, a method is proposed to determine how effective the series compensation of each transmission line is for improving the transient stability. This method is applied to the Nordic-32 test system to find the priorities of the transmission lines for installation of several series compensators. Simulation with industrial software shows the validity and efficiency of the proposed method., QC 20140123

This paper analyzes optimal tuning of power system stabilizers (PSSs) as the main resource for small-signal stability enhancement in power systems. The procedure is based on dynamic power system response and its frequency amplitude spectrum. Since the optimization model is very complex, there are difficulties in defining the algebraic relation between optimization criteria and PSS parameters and the authors concluded that classical optimization techniques are inappropriate for application in practice. To avoid these problems, application of artificial neural networks (ANNs) as efficient functional approximators is proposed. Optimal PSS parameters are determined by trust region based optimization, where the ANN represents an input function. Robustness of the optimization is ensured with the proposed ANN structure which considers an arbitrary number of different power system operating conditions (including single contingencies). For verification of the proposed methodology, two test systems are used: the New England-New York 68-node, 16-machine test system and the 75-machine dynamic model of the Serbian power system. Poorly damped modes of oscillation are identified and damped by installation of PSSs at appropriate locations with ANN-based optimally tuned parameters., QC 20120529

Since extended power outages causes severe stress on society and the restoration following a black out is a complex and time consuming task, efficient restoration strategies are needed. During the restoration, the power system undergoes continual changes and therefore it is subject to desired and undesired operations and failures which might be devastating. The main contribution of this paper is a new method to estimate the risk of an uncontrolled system separation in case of a loss of a transmission line or a transformer during a restoration process. The method in this paper assigns failure rates to the transformers and the transmission lines. Further, a graph theoretical method are used to find probability bounds for an uncontrolled system separation for a whole restoration sequence. In a numerical example are three restoration strategies applied to an IEEE 14 bus test system and evaluated. It is shown in the numerical example that the restoration strategy has an high impact on the probability for a system separation. © 2011 IEEE., Sponsors: Power and Energy Society (IEEE PES); Northeastern University College of Engineering© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20120117

Since extended power outages causes severe stress on society and the restoration following a black out is a complex and time consuming task, efficient restoration strategies are needed. During the restoration, the power system undergoes continual changes and therefore it is subject to desired and undesired operations and failures which might be devastating. The main contribution of this paper is a new method to estimate the risk of an uncontrolled system separation in case of a loss of a transmission line or a transformer during a restoration process. The method in this paper assigns failure rates to the transformers and the transmission lines. Further, a graph theoretical method are used to find probability bounds for an uncontrolled system separation for a whole restoration sequence. In a numerical example are three restoration strategies applied to an IEEE 14 bus test system and evaluated. It is shown in the numerical example that the restoration strategy has an high impact on the probability for a system separation. © 2011 IEEE., Sponsors: Power and Energy Society (IEEE PES); Northeastern University College of Engineering© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20120117

Since extended power outages causes severe stress on society and the restoration following a black out is a complex and time consuming task, efficient restoration strategies are needed. During the restoration, the power system undergoes continual changes and therefore it is subject to desired and undesired operations and failures which might be devastating. The main contribution of this paper is a new method to estimate the risk of an uncontrolled system separation in case of a loss of a transmission line or a transformer during a restoration process. The method in this paper assigns failure rates to the transformers and the transmission lines. Further, a graph theoretical method are used to find probability bounds for an uncontrolled system separation for a whole restoration sequence. In a numerical example are three restoration strategies applied to an IEEE 14 bus test system and evaluated. It is shown in the numerical example that the restoration strategy has an high impact on the probability for a system separation. © 2011 IEEE., Sponsors: Power and Energy Society (IEEE PES); Northeastern University College of Engineering© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20120117

Since extended power outages causes severe stress on society and the restoration following a black out is a complex and time consuming task, efficient restoration strategies are needed. During the restoration, the power system undergoes continual changes and therefore it is subject to desired and undesired operations and failures which might be devastating. The main contribution of this paper is a new method to estimate the risk of an uncontrolled system separation in case of a loss of a transmission line or a transformer during a restoration process. The method in this paper assigns failure rates to the transformers and the transmission lines. Further, a graph theoretical method are used to find probability bounds for an uncontrolled system separation for a whole restoration sequence. In a numerical example are three restoration strategies applied to an IEEE 14 bus test system and evaluated. It is shown in the numerical example that the restoration strategy has an high impact on the probability for a system separation. © 2011 IEEE., Sponsors: Power and Energy Society (IEEE PES); Northeastern University College of Engineering© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20120117

Since extended power outages causes severe stress on society and the restoration following a black out is a complex and time consuming task, efficient restoration strategies are needed. During the restoration, the power system undergoes continual changes and therefore it is subject to desired and undesired operations and failures which might be devastating. The main contribution of this paper is a new method to estimate the risk of an uncontrolled system separation in case of a loss of a transmission line or a transformer during a restoration process. The method in this paper assigns failure rates to the transformers and the transmission lines. Further, a graph theoretical method are used to find probability bounds for an uncontrolled system separation for a whole restoration sequence. In a numerical example are three restoration strategies applied to an IEEE 14 bus test system and evaluated. It is shown in the numerical example that the restoration strategy has an high impact on the probability for a system separation. © 2011 IEEE., Sponsors: Power and Energy Society (IEEE PES); Northeastern University College of Engineering© 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20120117

This paper proposes two mathematical structures for considering the market power effect of transmission capacity in transmission augmentation assessment. These mathematical structures use the concepts of monopoly rent and quantity withheld in economics for market power modeling in the assessment process of transmission augmentation. The simultaneous-move and sequential-move games in applied mathematics are used to model the interactions of the transmission network service provider, generating companies, and the market management company in the proposed mathematical structures. The solution concept of Nash equilibria is reformulated as an optimization problem, and the multiple Nash equilibria is tackled through an introduced concept termed worst Nash equilibrium. A numerical solution is developed to solve the proposed mathematical structures. The numerical solution is an island parallel genetic algorithm nested in a standard genetic algorithm. The six-bus Garver's example system and the IEEE 14-bus test system are modified and studied. The results prove the strong mechanism of the developed structures for modeling the market power effect of transmission capacity in the assessment of transmission augmentation., QC 20120217

This paper deals with the use of system identification techniques for estimating low-order black-box state-space models formodal analysis. It presents a method to estimate state-space models for large power systems with many controllable devices from noisy measurements. To excite the system low-energy pulses generated by the controllable devices are used. The input signals are the controllable set-points of the devices, the output signals are the speed signals of some generators obtained from Phasor Measurement Units (PMU). The Subspace State-Space System Identification (N4SID) and Prediction Error Method (PEM) are compared in sense of robustness using measurement with different signal to noise ratios noisy measurements. The method is applied in an extended version of the Cigré Nordic 32-bus test system. This model approach can be used directly for the design of a centralized controller coordinating the controllable devices with the aim to increase the damping in the system., QC 20110712

This paper describes two electrical distribution systems, Swedish Urban Reliability Test System (SURTS) and Swedish Rural Reliability Test System (SRRTS), which are representative of actual Swedish distribution networks. These test systems aim to serve as a basis for reliability and cost analyses of Swedish distribution networks and for studies of regulation policies. The project was conducted within a research programme of Elforsk, a Swedish industry research association. The challenge has been to make the test systems representative in terms of load, component and customer data as well as network topology. To ensure the similarity of the test systems to actual networks, industry representatives of major Swedish power distribution companies have been an integral part of the development process. This paper shows the result of a validation of the test systems against data compiled by the Swedish Energy Markets Inspectorate. The validation was performed for the reliability indices SAIDI and SAIFI. It was confirmed that the developed test systems are good representatives of actual distribution networks, and thus suitable for further research of distribution networks and for studies of regulation policies., QC 20110530

Transmission system structure has an essential effect on the reliability of the power system and electricity market performance, especially when producers bid strategically. As part of on-going research on the design of a robust algorithm for expansion planning of the transmission grid in the Australian electricity market, this paper presents a framework which addresses: (1) the security of power delivery to the load points of the transmission system in case of single line outages; (2) the minimization of transmission system lost load; (3) an efficient electricity market for market participants; (4) construction and maintenance costs of transmission augmentation options; and (5) operation efficiency of the transmission grid. The suggested algorithm benefits from the dynamic programming and sensitivity analysis approaches along with the aggregation method in its multi-criteria decision-making to locate the optimum configuration of a future transmission system. A set of indices, which account for impacts of the augmentation options of the transmission grid on five aforementioned reliability and market criteria, are proposed and used in the optimum framework for expansion planning of the transmission grid. Although the methodology is promising for expansion planning of the transmission system, considering the sensitivity analysis concept employed, the proposed methodology would be suitable to detect the sensitive areas of the transmission system to be expanded. The tool would be very useful in the case of large scale power systems for a smart reduction of the transmission expansion options. The proposed methodology has been applied to a 6-bus and a modified IEEE 30-bus test system to show the effectiveness of the sensitivity-based algorithm., QC 20120210

The market-based augmentation of the high voltage transmission systems as a legacy of the previous regulated regimes has been a challenging issue for the central transmission entities. The economic assessment framework for transmission upgrades or expansion projects, considering the interaction of the central transmission entity (CTE) with the electricity market management (MMC) company both as independent players needs to be addressed appropriately at least in the National Electricity Market, Australia. To assist in bridging this gap, this paper introduces a novel metric, namely, the L-Shape Area, for the economic assessment of the transmission expansion options. The proposed methodology employs a von Stackelberg game for the interaction modelling of the central transmission entity and the market management company. The upper subproblem minimises the objective of the CTE as the leader player and the lower subproblem solves the security-constrained economic dispatch as the follower subproblem. The bi-level programming problem has been solved by applying the Kuhn-Tucker optimality conditions to the follower subproblem and the use of a gradient search method to solve the resultant single level non-linear programming problem. A modified IEEE 14-bus test system has been used to show the effectiveness of the proposed formulation., QC 20120217

Transmission network was recognized as natural monopoly and almost everywhere subject to some kind of regulation in a restructured electricity market. The role of the transmission system is to provide an indiscriminate access for all market players along with an acceptable level of reliability and security. Regulating authorities have to decide about the augmentation investment. As an on going research on forming a robust algorithm for the expansion planning of transmission system in Queensland State, Australia, this paper presents two procedures for the quasi-optimal short-term augmentation of the transmission system. The proposed approaches can accommodate (1) Security of the power delivery to the load points of the transmission system in terms of single line outages (2) Minimization of the transmission system lost load (3) Providing full competitive electricity market for market participants (4) Construction and maintenance costs of transmission augmentation options and (5) Operation efficiency of the transmission grid in their planning frameworks. Each expansion option of the transmission system is evaluated by the aforementioned criteria through designation of a set of indices. The proposed procedures benefits from the concepts of the sensitivity analysis and dynamic programming as well as aggregation method, weighted sum function, in their multi-criteria decision making. The introduced procedures are very promising in case of short term expansion planning of the transmission system. Considering the sensitivity analysis concept employed, in case of long term planning the method is appreciable in smart detection of the suitable zones for expansion. The procedures would be very useful in case of large scale power systems. A 6 bus test system and modified IEEE 30 bus test system are used to validate the effectiveness of the proposed procedures., QC 20120217

This paper presents a simultaneous active and reactive power/voltage dispatch methodology using a mixture of continuous and discrete control variables. The continuous control variables are active power and reactive power/voltage magnitudes of generator buses, while the discrete ones are transformer-tap settings. The Lambda iteration based economic dispatch is used to minimize the fuel cost and active power dispatch among the generators. During this process, the voltage magnitude of load buses may move away from the desired value. The genetic algorithm is applied for optimal reactive power/voltage dispatch among generators and determination of tap settings of under load tap changers (ULTCs). This results in globally improvement of voltage regulation of load buses. Considering the fact that the reactive power/voltage of generators are continuous variables while the transformer tap settings are discrete variables, a method is proposed to combine these variables into one suitable chromosome. The IEEE 30-bus test system is used to illustrate the effectiveness and feasibility of proposed approach., QC 20120209

We evaluated experimental liquid and solid pharmaceutical formulations using specific enzymatic in vitro tests to reveal glutathione-reductase, catalase and NADPH-oxidase activity with an aim to choose the most promising formulations for further study and development of products for treatment of inflammatory conditions of the oral cavity. The above mentioned tests allow identification of substances with antimicrobial and immune stimulating activity respectively. Herbal extracts Eucalimin and Estiphan were used as reference products. As a result, differences in antimicrobial and immune stimulating activity of the formulations were found, and the most promising formulations were chosen for further study and development of products with antimicrobial and immune stimulating activity.