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Present research studies the formation of a digital footprint based on the characteristics of computer hardware to identify APCS users. The authors of the article propose to form a digital footprint from significant static and dynamic hardware characteristics. The main elements of the system and their functionality are reviewed, and the characteristic features are noted. In addition to the selection of characteristics based on analysis, selection is carried out based on a computational experiment, which consists in testing the hardware components of a computer using tests of various types. The effective types of tests are determined that can be carried out and provide the desired level of uniqueness of the dynamic hardware performance associated with the stability index. The results of the article, obtained by the authors, could be used in future works, both for improving and generalizing theoretical results, and for practical application in the problem of identifying APCS users.

In this study, the FPA (flower pollination algorithm) method is used for optimize the location and capacity of photovoltaic distributed considering voltage stability index (VSI). The proposed method is used in the KTN 03 bus system case study (Yogyakarta city). This operation is conducted for a half-day (10:00 AM - 2:00 PM) operation. There are two scenarios used in this study. Scenario 1 with PV placed on one bus and scenario 2 assuming all buses can be installed PV.The value generated in the two-scenario simulation, the total loss becomes 3.060 MW in scenario 1 and 3.1459 MW in scenario 2. Increased stability index values are seen on all lines. However, the smallest VSI values were obtained at lines 9, 18, and 35. The total energy loss in scenario 1 is 1.5300 MWh and scenario 2 is 1.5729 MWh. The PV energy share was obtained for 4.72% and 5.86% in both scenarios.

The frequent happenings of voltage collapse in a power system in the recent time as a result of continuous increase in power demand has been a concern and has posed a great threat to power system utilities. In this paper, to predict a voltage collapse bus, an approach named critical bus voltage stability index (CBVSI) which is based on the voltage deviation of the load bus of the system, the maximum loadability and the total number of step size taken to reach the minimum permissible load of each load bus is suggested. The bus voltage deviation index (BVDI) of each load bus is first computed at each reactive power load variation. The suggested voltage stability index of each load bus is thereafter found. A comparative assessment of the suggested CBVSI with the conventional fast voltage stability index (FVSI) is also done. Results of the simulation obtained show that the method based on CBVSI could be of great significance and serve as an alternative tool for power system engineers in the operation and planning of the system.

Short-term voltage stability is closely related to the dynamics and stability of load models. After the identification of the load model parameters, the load stability can be analyzed. In this paper, a load model parameter based load stability index is proposed, with desirable properties of case independency, sufficiency and monotonicity. The composite load model structure together with the identification method is introduced. Then, the dynamics of the load model under voltage disturbance are analyzed and the basic form of the load stability index is proposed. After that, the basic index is modified in order to be more sufficient based on the simulation results in WSCC 9 bus system and then the final form of the index is given. Finally, the index is validated based on the simulation results to show that it can be used to reflect the ability of a load model to maintain the power consumption stable.

Voltage Stability analysis is a very vital and challenging issue of the power system and maintains the stable bus voltage profile is the biggest problem. Here we applied Modal analysis, Line voltage stability indices, to study voltage collapse problem and find the weakest bus in the test bus system by using the PV curve. After investigating the weak bus, we have injected the shunt devices for maintaining the voltage profile. All parameter decided for voltage collapse by the PSAT MATLAB simulation. The modal analysis gives the Eigenvalue and Participation factor and these values help to find the weakest node in the system. Here see that smallest Eigenvalue gives the voltage collapse point and. Line Voltage stability Indices help to find the weakest line corresponding to the weakest bus. We proposed the comparative analysis of three line indices Line Stability Index, Fast Voltage Stability Index, and Line Stability or Quality Factor. The PV curve gives the voltage collapse point with and without injecting shunt devices in the test bus system.

Previous studies mostly applied the nonnegative matrix factorization algorithm (NNMF) upon the reaching tasks or some relatively stable activities to extract the muscle synergies aiming for observing the coordination of muscles in humans. However, few studies have used this algorithm in the tracking task since its high complexity and unpredictability, which means that the muscle synergies become more unstable and are hard to embody the neural mechanisms behind the human motion. Therefore, we implemented NNMF on tracking tasks and calculated two synergy indices, including the synergy stability index (SSI) and synergy coordination index (SCI). $\mathrm {S}\mathrm {S}\mathrm {I}_{\mathrm {w}}$ and $\mathrm {S}\mathrm {S}\mathrm {I}_{\mathrm {C}}$ respectively quantify the similarity between synergies and activation coefficients, and SCI indicates the size of the synergy space. In our results, $\mathrm {S}\mathrm {S}\mathrm {I}_{\mathrm {w}}$ was about 0.8, $\mathrm {S}\mathrm {S}\mathrm {I}_{\mathrm {C}}$ was nearly 0.3 and SCI was 0.6. The value of these indices indicated that humans tended to keep synergies stable and control them more flexibly by changing the activation time and amplitudes when undertaking changeable and complex tasks.

Load demand increase (especially reactive load) and limited sources of generation has led to operate the power system near its voltage instability point. Consequently, the issue to determine voltage stability before voltage collapse has become an interesting subject for many researchers. Therefore, many voltage stability indices were been suggested to test the distance of power system from voltage breakdown.In this paper, two line voltage stability indices are been conducted. They are Line stability index (Lmn), and fast voltage stability index (FVSI). They are been applied to determine the weakest bus in IEEE 30-buses test system. Then three types of FACTS compensation, shunt, series and hybrid (shunt and series) are been used to assist voltage stability. The results show that shunt compensation is more efficient than the other two types.

The prime focus of this study is to find total subsidence in Burgan oil field, Kuwait using PSInSAR technique. Permanent scatter candidates (PSC) were then selected based on amplitude stability index. Total subsidence was found to be varying between −10 and 10 mm per year on the Displacement Map. PsInSAR has been successfully implemented for finding subsidence between 2008 and 2011 in Burgan Oil field.

This study presents a stability index based analytical technique for the optimal siting and sizing of different types of Distributed Generator (DG) unit in the distribution networks (DNs) with the objective to reduce line losses, improve voltage profile, and decrease pollution level. In order to identify the most appropriate location for DG placement, Voltage Stability Index (VSI) is utilized. A new formula is developed for the purpose of converting the multi-objective functions into a single-objective that is then minimized using the proposed analytical approach to obtain the optimal rating of DG. Furthermore, with an aim to judge the technical and environmental impact of DG, innovative and unique formulas are developed in this paper. Depending upon the reactive power absorption or generation ability, DG is classified into three types and using the proposed methods, optimal allocation is conducted separately for each type at different loading conditions. In addition, an analysis is executed based on their optimal performances to identify the most suitable type of DG for integrating into the power system.

Voltage is the essential part of the power system response and it is significant aspect of system stability and its safety. Outcome of voltage imbalance is results in monotonically declining voltages. FACTS devices play an imperative role in upgrading the functioning of power system so need to be placed optimally. PV evaluation is broadly used in the industry for investigating voltage security problems. However, it doesn't specify any data concerning uncertain facilities with voltage stableness issues in the system. This paper introduces a line stability index method to decide weakest bus of the system to placed STATCOM optimally for rising voltage magnitude.

In this study, we use an accelerometer sensor to measure human postural signals during a dynamic task. In previous studies, the step stability index (SSI) has been used to assess human balance via similar sensors. However, the placement of the 3 dimensional sensor differed, placed on the lower back of the subjects. To improve the detection method, we placed the accelerometer on the shoe. The purpose of this research is to compute the SSI, to evaluate whether human balance can be objectively measured with an accelerometer. The results are compared with dynamic centre of pressure (COP) measurements obtained from a force plate that serves as the ground truth. The complexity index (CI) is calculated from dynamic COP to compare with the results of SSI.

In this paper we introduce the Collapse Index, a new measure of the relevance of individual formal concepts in a concept lattice, the application of which improves the performance of concept pruning and reduces the bias against "outlier" concepts. The measure determines the relevance of a formal concept in the lattice by calculating the minimum number of objects which need to be removed from the domain before the formal concept collapses. We demonstrate the effectiveness of the Collapse Index as a measure of pattern selection by comparing the collapse indices found in two datasets. We cover the case where the two datasets are disjoint and the case where one dataset is a subset of the other. Results are contrasted to those of the Stability Index measure.

The intent stability index represents an useful relevancy measure of the extracted patterns in the FCA data mining method. We describe this kind of relevancy measure for the so-called one-sided concept lattices, which represent a fuzzy generalization of the classical FCA. The basic properties of the stability index and some experimental results concerning this index conducted on randomly generated dataset are discussed.

This paper proposes a new algorithm for Distributed Generator placement and sizing in radial distribution system based on a novel index. The index is developed considering stable node voltages referred as power stability index (PSI). A new analytic approach is adopted to visualize the impact of DG losses, voltage profile, and voltage stability. The proposed method is tested on 12-bus and 69 bus radial systems.

Transferring large amount of power, from generations to end users, may reduce system stability margin. Therefore, the evaluation of maximum power transfer capability is required. This paper proposes the calculation of maximum power transfer capability which can satisfy N-1 contingency by re-dispatching the generation in load area, using Particle Swarm Optimization (PSO) method. The stability of system is specified by PQVSI (a stability index). The proposed method is tested on the 28 buses-southern transmission system of Thailand, and the result is promising.

This paper presents the comparison between Stability Indexes value used for load shedding of the islanded distribution network. In this work, 2 stability indexes, namely Power Stability Index (PSI) and Stability Index (SI) are used as Stability Index Ranked (SIR) to shed the loads. The proposed Under-Frequency Load Shedding (UFLS) algorithm is implemented the online stability index ranked as main priority of load to be shed. The performance of frequency and voltage are monitored in the existing Malaysia's Distribution network interconnected with two mini hydro generations. The simulation results show that the PSI possesses the better and improved voltage profile rather than SI index, while stabilizing the system frequency.

This paper discusses the performance of two different line voltage stability indices previously studied in literature the Line stability Index (Lmn) and Voltage Collapse Point Indicators (VCPI). The objective is to identify which index is most suitable for being used in control applications. The results presented here will provide a first indication. The indices were tested in the IEEE 39-bus system. The RTDS simulator was used to create data sets and the indices where computed using the control block components for real time operation. This method was chosen to have the values of the indices available for future development of control algorithms based on stability indices.

This paper presents the analysis of a distribution system connected with distributed generation (DG) units. The developed technique is based on the steady state voltage stability index. The weakest branches in the distribution system which are more likely go to the instability region are selected for DG allocation. Two optimization methods are utilized to find out the size of the DG corresponding to minimum losses or minimum stability index. The Newton-Raphson load-flow is used to find the steady-state solution of the studied distribution system. The AMPL software package is utilized for evaluating the size of the DG units. The developed methods are tested using a 90-bus distribution system with a variety of case studies.

Over the past two decades, with the rapid urbanization in Guangzhou, urban fringe area has been experiencing drastic land use changes. In this paper, taken the extended south area of Guangzhou as a typical urban fringe area example, land use structure and fractal model of the study area in 1990, 1995, 2000 and 2005 have been established from Landsat TM images by adopting GIS and RS technology. Dynamic degree, fractal dimension and stability index of the main land use types in each year are calculated. The results show that: from 1990 to 2005, land use of the extended south area of Guangzhou was experiencing significant changes under the strong forces of urbanization of core area in Guangzhou. According to the changes characteristics of land use, two phases of change can be interpreted: First, from 1990 to 1995, the structure of land use was changing drastically. In this period, the increase of construction land and decrease of farmland are the dominant processes, which greatly increased the fractal dimension and decreased the stability index. Second, from 1995 to 2005, changing speed of land structure was slowing down, farmland and forestry started to increase, along with the increase of fractal dimension and stability index became slighter, regional structure change of land use started to present a positive tendency.

A microbial transglutaminase was used to modify soybean protein isolates (SPI) in the presence of glucosamine. SDS-PAGE analysis revealed that glucosamine conjugation and cross-linking occurred during reaction. A modified SPI product with glucosamine conjugation of 3.2 mol·mol−1 SPI was prepared, and its emulsifying or gelation properties were evaluated. Analysis results showed that its emulsifying activity index and stability index were 98.0 m2· g−1 and 89.5%, which were about 26 and 38% higher than the original SPI. The heat-induced gel of the modified SPI product also exhibited better gelation property. This technique is an effective approach to improve some functional properties of SPI.

A systematical approach that can synthesize system contingencies into probabilistic PSS design is developed. A critical contingency screening is first conducted by a ranking of contingencies according to a probabilistic small signal stability index. A multi-objective optimization model is formulated to seek satisfactory system damping performance under both pre-contingency and post-contingency situations. A recursive Particle Swarm Optimization (PSO) technique is then used to solve the optimization model. Performance of the proposed model and solution is tested and investigated on an eight-machine system and The potential and superiority of the proposed method over other two intelligence computation methods is reported.

Corporate divestiture is the earliest method of contracting capital operation. With the development of capital market, the evaluation of performance of corporate divestiture is becoming more and more important. There are usually two methods to evaluate the performance of divestiture, that is event study approach and accounting index approach, but they both have some shortcomings. Based on the methodology of data envelopment analysis, this article provides a model to evaluate the divestiture performance based on stability index. The article also illustrates the selection of the input and output indexes and the calculation and treatment of data. The method presented in the article can provide comparative important information of the corporate divestiture.

The agility property of interorganizational workflow is one of the critical success factors in the business collaboration. Based on Petri nets, the agility analysis framework of interorganizational workflow with four layers is proposed. And the two evaluation indices of the agility property of interorganizational workflow are presented. The element agility index focuses on the analysis of elements number in the interorganizational workflow, and the connection stability index is introduced to investigate the dependency relation among workflow elements. At last, an application example is given.

This paper presents the simplified design of a PI controller for a higher-order plant by using the concept of plant model reduction and coefficient diagram method with less number of stability index gamma i. The higher-order plant model is first reduced to be a lower-order plant model by ignoring its non-dominant poles. Secondly, the PI controller is designed for the lower-order plant model by using coefficient diagram method with the appropriate values of stability index in order to obtain its system response without overshoot. Thirdly, the designed PI controller is used to control the original higher-order plant. The simulation results show that the PI controller designed from the lower-order plant model is sufficient for controlling the original higher-order plant with acceptable performance

A way of assessment of the transient stability reserve, using the trajectory of the dynamic transition, received by numerical integration of the dynamics equations for considered electric power system (EPS) at given disturbance, is reported. For each moment of time according to numerical solution of a transient process the Lyapunov function of energy type is calculated. By observation of its change in time the maximal value of potential energy is determined. It is compared with critical one, calculated as the nearest local maximum on the beam, going from a point of balance for post-emergency state in a direction of a found local maximum on a trajectory. This beam simulates increase of disturbance intensity, causing considered transient. Conservative model of EPS is used for assessment of the transient stability reserve, movement of ";mass centre"; is excluded from full movement of system, which the numerical decision gives, and stability on Lyapunov is considered only for mutual movement of machines. An error of calculation by offered method of limiting value of disturbance (the value of the shunt of nonsymmetrical short circuit) for the real power system is estimated about 4%. A procedure of transient stability assessment for current states of the system on the set of disturbances is offered. It uses ranking disturbanced states with the help of stability index (stability reserve). Checking steady state stability of power system is fulfilled by dynamic method.

This paper is about hybrid methods of combining energy function analysis and conventional time-domain simulation for transient stability assessment. In particular, a new approach called marginally unstable injection (MUI) for developing a more accurate transient stability index is presented. An energy margin for transient stability assessment based on a reduced energy function is formulated. One implementation of the proposed approach is to use a feedback-controlled sequence of short pseudo-faults to impel the stable system to a marginally unstable state. The conceptual differences between MUI and some earlier approaches of hybrid methods are discussed. For illustrative purposes, the technique developed is applied to a 700-bus North America system. Some numerical results are presented.