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Differential equation load flow (DELF) is an innovative approach to convert a load flow model to a fictitious dynamic system. DELF solves the entire time‐domain analysis of a dynamic system trajectory rather than solving load flow equations repeatedly in a set of conditions. The static available transfer capability (ATC) determination algorithm is specified through a method called the approximation of the path of the minimum distance method. In this method, instead of a repeated power flow, only three system operating points are used. An estimation of the potential energy boundary surface was also employed to determine the transient stability in an attempt to correct previous methods. A combination of static method and transient stability led to a combined approach to dynamic ATC computation. This paper proposes a truly effective and precise method to assess Dynamic ATC using the differential equation load flow considering the first contingency (n − 1) situations and the intact system condition. For various multilateral and bilateral transactions, this method was successfully implemented on 39, 118‐ and 300‐bus IEEE, 145‐bus Iowa‐State, the west of Iran (1153‐bus), and Mashhad MV distribution network (4438‐buses) systems. The results showed a better suitability, a higher speed and accuracy than other dynamic ATC methods.

The two-dimensional streamline curvature through-flow modeling of turbomachinery is still a key element for turbomachinery preliminary analysis. Basically, axisymmetric swirling flow field is solved numerically. The effects of blades are imposed as sources of swirl, work input/output and entropy generation. Although the topic is studied vastly in the literature for compressors and turbines, combined modeling of the transonic fan and the downstream splitter of turbofan engine configuration, to the authors’ best knowledge, is limited. In a prior study, the authors presented a new method for bypass fan modeling for inverse design calculations. Moreover, new set of practical empirical correlations are calibrated and validated. This paper is an extension of this study to rapid off-design analysis of transonic by-pass fan systems. The methodology is validated by two test cases: NASA 2-stage fan and GE-NASA bypass fan case. The proposed methodology is a simple extension for streamline curvature method and can be applied to existing compressor methodologies with minimum numerical effort.

With the steady growth in distributed generation, more and more attention is paid to low voltage distribution networks. Many of these studies neglected the fact that most of the consumers and small generating units are phase-neutral connected in a multipoint-grounded neutral system – at least in low voltage (LV) distribution systems that is common in Europe. If an equipment utilizes local regulation, it also detects this phase-to-neutral voltage. The effect of neutral can be substantial considering the narrow band of regulation and/or with equipment sensitive to neutral-earth voltage. Until now, the correct modelling of these kind of networks has been scarce; some of them face accuracy or convergence problems with these networks. This article presents an example for the problem and a new alternative calculation method to enable fast, simple-to-implement and accurate load flow calculation for unbalanced networks. Therefore, studies and control algorithms can rely on a more precise model.

One of the major challenges of ancient manuscripts recognition is character segmentation. Because of many distinct features of ancient documents (thick characters, overlapping and touching characters), character segmentation is a very difficult task. Devanagari ancient manuscripts consist of vowels, consonants, modifiers, conjuncts and compound characters. Using existing techniques, segmentation of overlapping and touching characters is problematic. In this paper, an iterative character segmentation algorithm is presented for ancient documents in Devanagari script. At the beginning, the lines are extracted from the ancient documents by dividing the document image into vertical stripes and then using piecewise horizontal projection profiles. After that, these lines are segmented into words using vertical projection profiles and finally, words are segmented in characters using an iterative algorithm. In each iteration, character segmentation is refined. In the present work, we have proposed a new algorithm with the name ‘Drop Flow Method’ to find the segmentation path between touching components. The proposed algorithm can segment touching characters and 96.0% accuracy has been achieved for complete segmentation of Devanagari ancient manuscripts.

In this paper, a modified backward/forward sweep (BFS) load flow algorithm is proposed to solve power flow for islanded droop-controlled ac microgrids. The proposed method has been formulated such that the system frequency is one of the system’s unknown variables which is typical for an islanded network justifying further the absence of a slack bus. As a result, new equations have been systematically developed and incorporated with the conventional BFS method. The modified BFS method has been applied to the 33-bus test system and the results obtained are compared with simulation results from the direct BFS method as well as PSCAD/EMTDC. In comparison to the conventional methods, the proposed method is accurate, simple, and easy to implement thus serving as a useful tool for microgrid analysis and planning.

The clinical importance of blood group (BG) antigens is related to their ability to induce immune antibodies that can cause hemolysis. Yet, ABO and D (Rh) are still considered to be the key antigens for healthy blood transfusion and secondary antigens are the next priority. Serological typing is the most widely used typing method. Rapid and accurate blood grouping plays an important role in some clinical conditions, rather than conventional techniques. Hence, developing a simple and economical model for rapid blood grouping would facilitate these tests. In recent decades, paper-based microfluidics such as μPADs has gained much interest in wide application areas such as point-of-care diagnostic. In this study, we evaluated μPADs that are performed for blood grouping and its recent progress. A comprehensive literature search was performed using databases including PUBMED, SCOPUS, Web of Science and Google Scholar. Keywords were blood grouping or typing, paper analytical device, rapid test, etc. After investigation of search results, 16 papers from 2010 to 2020 were included. Further information in detail was classified in Table 1. Generally, two principles for blood typing μPADs are introduced. The lateral chromatographic flow method and the vertical flow-through method that detects BG in a visual-based manner. To detect results with acceptable clarity many factors and challenges like paper, blood sample, buffer, Ab and RBC interaction and also μPADs stability need to be considered, which are discussed. In conclusion, the simplicity, stability, cheapness, portability and biocompatibility of μPADs for blood grouping confirming its utility and also they have the capability to robust, universal blood-grouping platform. Table 1 Summary of blood grouping tests using paper-based analytical devices Antigens Type of diagnosis Validation method Sample No Accuracy Action time Paper type Stability Sample dilution Buffer Ref A, B, Rh Forward volunteers records 5 - - Whatman No. 4 - 1/2 PBS* (Khan et al. 2010) A, B, Rh Forward gel assay test and conventional slide test 100 100% 1 min Whatman No. 4 and Kleeenex paper towel 7 Days in 4 °C 1/1 NSS (Al-Tamimi et al. 2012) A, B, Rh Forward gel card assay 99 100% 20 Sec + Washing Kleeenex paper towel - 1/1 NSS (Li et al. 2012) A, B, Rh Forward - - - - Kleeenex paper towel - 45/100 PSS (Li et al. 2013) A, B, Rh Forward gel card assay 98 100% 1.5 min Kleeenex paper towel - 85/100 PBS (Guan et al. 2014b) C, E, c, e, K, Jka, Jkb, M, N, S, P1, and Lea Forward gel card assay 266 100% - Kleeenex paper towel - 1/1 NSS (Li et al. 2014b) A, B, Rh Forward and Reverse conventional slide test 96 ≈ 91% 10 min Whatman No. 1 21 Days in 4 °C 1/2 NSS (Noiphung et al. 2015) C, c, E, e, K, k, Fya, Fyb, Jka, Jkb, M, N, S and s, P1, Lea and Leb Forward - 478 - - Kleeenex paper towel - 1/1 NSS, PBS (Then et al. 2015) A, B Forward and Reverse conventional slide test 76 100% 5-8 min Whatman No. 4 38 Days in 4 °C 1/4, 1/1 NSS (Songjaroen and Laiwattanapaisal 2016) D, K Forward volunteers records 210 - 7.5 min Kleenex paper towel - 1/1 NSS (Yeow et al. 2016) A, B, c, e, D, C, E, M, N, S, s, P1, Jka, Jkb, Lea, Leb, Fya, and Fyb Forward and Reverse gel card assay 3550 ≈100% 30 s Fiber glass and cotton linter 180 Days in 25 °C 45/100, 1/1 PBS (Zhang et al. 2017) A, B Forward conventional slide test 598 100% 3 min Whatman No. 113 14 Day in 4 °C 1/1 NSS (Songjaroen et al. 2018) A, B, Rh Forward conventional slide test - - 30 Sec + Washing Unrefined sisal paper - 1/2 NSS (Casals-Terré et al. 2019) A, B, Rh Forward - - - - Whatman No.1 - 1/1 NSS (Ansari et al. 2020) ABORh Forward and Reverse conventional slide test - 100% Unrefined Eucalyptus papers - 1/2 NSS, PBS (Casals-Terré et al. 2020) A, B, Rh Forward - - - 30 Sec + Washing Whatman No. 4 modified with chitosan ≥ 100 days in 25 °C 1/1 NSS (Parween et al. 2020)

Clustered Regularly Interspersed Short Palindromic Repeat-CRISPR-Associated (CRISPR-Cas) system has improved the ability to edit and control gene expression as desired. Genome editing approaches are currently leading the biomedical research with improved focus on direct nuclease dependent editing. So far, the research was predominantly intended on genome editing over the DNA level, recent adapted techniques are initiating to secure momentum through their proficiency to provoke modifications in RNA sequence. Integration of this system besides to lateral flow method allows reliable, quick, sensitive, precise and inexpensive diagnostic. These interesting methods illustrate only a small proportion of what is technically possible for this novel technology, but several technological obstacles need to be overcome prior to the CRISPR-Cas genome editing system can meet its full ability. This chapter covers the particulars on recent advances in CRISPR-Cas9 genome editing technology including diagnosis and technical advancements, followed by molecular mechanism of CRISPR-based RNA editing and diagnostic tools and types, and CRISPR-Cas-based biosensors.

A new, improved modified Newton Raphson (IMNR) load flow method is proposed for AC islanded microgrids. The absence of a strong slack bus and the droop control of distributed generation (DG) units pose challenges that can not be tackled by the conventional load flow techniques. The proposed load flow method extends the traditional Newton-Raphson technique to the islanded microgrid case with complex loads. The proposed load flow method has been tested on three different networks, and the performance of the proposed method has been compared with other methods. The IMNR method is fast and takes fewer iterations to converge. The proposed method is used to analyze the loadability of islanded microgrid, and the results are presented.

Nowadays, the non-optimal placement of the shunt capacitors in distributed electricity systems may increase the total active power loss and lead to the voltage instability. Therefore, many researchers have recently focused on optimization of capacitor placement problem in radial and meshed distribution grids aiming to minimize transmission losses and improve the overall efficiency of the power delivery process. This chapter aims to present a backward-forward sweep (BFS) based algorithm for optimal allocation of shunt capacitors in distribution networks. The total real power loss of the whole system is minimized as the objective function. Moreover, the feeder current capacity and the bus voltage magnitude limits are considered as the optimization constraints. In addition, it is assumed that the sizes of capacitors are the known scalars. The 1st capacitor is considered to be located at the 1st bus of the test system. Then, the BFS load flow is run and the objective function is saved as 1st row and 1st column component of a loss matrix. Secondly, the 1st capacitor is assumed to be installed at bus 2 and the BFS load flow is run to obtain objective function as 2nd row and 1st column component of loss matrix. When all buses are assessed for installation of capacitor 1 and losses are calculated in each scenario, similar analyses are carried out for the 2nd capacitor bank and the values of the active power loss are saved as the 2nd column of the loss matrix. The same strategy is applied to other capacitors. Finally, a loss matrix is formed with number of rows and columns equal to the number of buses and shunt capacitors, respectively. The best places for installation of capacitors are determined based on the components of the loss matrix. Simulation of BFS based capacitor placement problem is conducted on the 33-bus distribution network to demonstrate its robustness and effectiveness in comparison with other procedures.

Using the discrete cost sharing model with technological cooperation, we investigate the implications of the requirement that demand manipulations must not affect the agents’ shares. In a context where the enforcing authority cannot prevent agents (who seek to reduce their cost shares) from splitting or merging their demands, the cost sharing methods used must make such artifices unprofitable. The paper introduces a family of rules that are immune to these demand manipulations, the pattern methods. Our main result is the characterization of these methods using the above requirement. For each one of these methods, the associated pattern indicates how to combine the technologies in order to meet the agents’ demands. Within this family, two rules stand out: the public Aumann–Shapley rule, which never rewards technological cooperation; and the private Aumann–Shapley rule, which always rewards technology providers. Fairness requirements imposing natural bounds (for the technological rent) allow to further differentiate these two rules.

Through-flow method is still widely applied in the revolution of the design of a turbomachinery, which can provide not merely the performance characteristic but also the flow field. In this study, a program based on the through-flow method was proposed, which had been verified by many other numerical examples. So as to improve the accuracy of the calculation, abundant loss and deviation models dependent on the real geometry of engine were put into use, such as: viscous losses, overflow in gaps, leakage from a flow path through seals. By means of this program, the aerodynamic performance of a certain high through-flow commercial fan/booster was investigated. On account of the radial distributions of the relevant parameters, flow deterioration in this machine was speculated. To confirm this surmise, 3-D numerical simulation was carried out with the help of the NUMECA software. Through detailed analysis, the speculation above was demonstrated, which provide sufficient evidence for the conclusion that the through-flow method is an essential and effective method for the performance prediction of the fan/booster.

Purpose The purpose of this paper is to understand how the Wyoming Quit Tobacco Program (WQTP) is used by its subscribers and to better understand how WQTP might be connected to WQTP outcomes. Design/methodology/approach Provider intake and program use data corresponding to the May 2010 to March 2012 enrollment period (n=6,168) were used. All program flows were constructed using frequencies and crosstabs, based on an initial theoretical model prepared by the program provider. Data were adjusted based on analysis that explored all possible uses beyond those specified by the provider’s theoretical model. Findings Although the authors could replicate the structure – the theoretical model constructed by the provider – the authors were not able to replicate all relationships between program components. The authors also found that most individuals signed up and used web-based services. Only a few individuals finished their treatment regimens in the way they were designed to be used by the program. Originality/value This is the first case study to use a program flow method to investigate an entire comprehensive tobacco cessation program structure and delivery.

The objective is the strategic placement of multiple DGs of different types to reduce the active power loss of the overall distribution network by choosing the optimal size and location of the DG. As study shows that randomly selecting location and sizing leads to higher power loss than network without DGs. This paper discusses an exhaustive search approach based on direct load flow method to find the location and size for optimal power loss of multiple DGs of all types in the distribution systems. The proposed method is developed and IEEE standard test systems (16-bus and 33-bus) is used to test the methodology.

Modern power distribution systems are installed with a number of distributed power generation. Increased integration of distributed power generation makes the distribution system vulnerable to unbalanced operating conditions. This would then require the support of Flexible AC Transmission System (FACTS) devices for a smooth operation of the distribution system. Unbalanced power system operation requires an unbalanced load flow analysis in order to assess true system feasibility. This paper presents an innovative unbalance load flow analysis method with the presence of unbalanced operation of SVCs (Static Var Compensators) and STATCOMs (STATic synchronous COMpensators). Unlike the existing methods, the proposed method applies reduced steps in the calculation, and the parameter limits of FACTS devices are dynamically determined in an iterative process. Case studies demonstrate its improved convergence characteristics, reduced computing demand and the robustness of the solution.

Transmission reliability margin (TRM) is the amount of transmission capability which ensures the transmission network security under a reasonable range of uncertainty in system operating condition. This paper describes a technique for TRM estimation by modified DC load flow method considering transmission line admittances and system load as distress. The technique is applied to the IEEE 6 bus system, and results are compared with previous results for validation.

In this paper, a load flow algorithm for unbalanced islanded Microgrids (MGs) is developed considering both the multigrounded low voltage (LV) and the medium voltage (MV) network. The method is based on the implicit Z BUS load flow method and it can be applied even in highly meshed MGs regardless of the R/X ratio of lines. It presents fast convergence, low computation time and high robustness. In our analysis we consider a variety of transformer configurations and step voltage regulators. Simulations were conducted in IEEE 4-nodes, 6-nodes and in a highly meshed network of 749 MV and LV nodes.

This study proposes a modified formulation for the popular fast decoupled load flow method to facilitate automatic incorporation of reactive power flow related constraints, i.e. generator reactive power and in-phase transformer tap limits. This formulation has been developed by viewing each device constraint as a set of complementary conditions and adopting the complementarity framework to define one equation to represent this set. The original set of load flow equations is augmented with this set of new equations representing the device constraints and solved to get the adjusted solutions directly. This approach is a significant departure from all the earlier approaches. The earlier approaches generally adopt a two-stage scheme. In the first stage, an approximate unadjusted solution is obtained and in the next stage, adjustments are attempted by ad hoc schemes. The new formulation presented here permits handling both the reactive power related constraints simultaneously. However, it can also be used in situations where only one type of adjustment is needed. Two alternate algorithms in complementarity framework based on mixed complementarity problem and non-linear complementarity problem formulations are presented here. Simulation results are presented to provide evidence of the impressive performance of the new algorithms as compared with the existing ones.

In this paper, we will focus on comparing the two methods for optimisation of intersection control. The first method is a saturation flow method, the second method is an expert system that divides the time for each vehicle a given crossing direction based on expert knowledge. For both methods, simulations are created based on real data of a selected crossroad in the city of Ostrava. Based on these simulations, the methods are compared. Subsequently, the comparison is evaluated together with a description of the advantages and disadvantages of the individual methods. The comparison is provided based on real traffic data of a selected crossroad in the city of Ostrava.

A novel measurement approach for power-flow analysis in medium-voltage (MV) networks, based on load power measurements at low-voltage level in each secondary substation (SS) and only one voltage measurement at the MV level at primary substation busbars, was proposed by the authors in previous works. In this paper, the method is improved to cover the case of temporary unavailability of load power measurements in some SSs. In particular, a new load power estimation method based on artificial neural networks (ANNs) is proposed. The method uses historical data to train the ANNs and the real-time available measurements to obtain the load estimations. The load-flow algorithm is applied with the estimated load powers, and the MV network state variables are obtained. The proposed method is validated for the real MV distribution network of the island of Ustica. The loads of selected SSs are estimated for two full days of different seasons. In comparison with previous works, satisfactory results are obtained in terms of uncertainty in the calculated power flows, thus suggesting the applicability of the proposed method for real-time monitoring of MV distribution networks.

Most of the top performing action recognition methods use optical flow as a “black box” input. Here we take a deeper look at the combination of flow and action recognition, and investigate why optical flow is helpful, what makes a flow method good for action recognition, and how we can make it better. In particular, we investigate the impact of different flow algorithms and input transformations to better understand how these affect a state-of-the-art action recognition method. Furthermore, we fine tune two neural-network flow methods end-to-end on the most widely used action recognition dataset (UCF101). Based on these experiments, we make the following five observations: (1) optical flow is useful for action recognition because it is invariant to appearance, (2) optical flow methods are optimized to minimize end-point-error (EPE), but the EPE of current methods is not well correlated with action recognition performance, (3) for the flow methods tested, accuracy at boundaries and at small displacements is most correlated with action recognition performance, (4) training optical flow to minimize classification error instead of minimizing EPE improves recognition performance, and (5) optical flow learned for the task of action recognition differs from traditional optical flow especially inside the human body and at the boundary of the body. These observations may encourage optical flow researchers to look beyond EPE as a goal and guide action recognition researchers to seek better motion cues, leading to a tighter integration of the optical flow and action recognition communities.

The emergency evacuation route planning of cruise ships directly affects the safety of all crew members and passengers during emergencies. Research on the planning of emergency evacuation routes for cruise ships is a frontier subject of maritime safety. This study proposes an improved ant colony system (IACS) to solve the evacuation route planning of crowds on cruise ships. The IACS, which is different from common single-path ant colony system (ACS) evacuation algorithms, is used to solve the multipath planning problem of crowd evacuation from cruise ships by considering crowd density and speed in the model. An increasing flow method is introduced into the IACS to improve the efficiency of the proposed algorithm. Numerical experiments show that this method meets the requirements of evacuation analysis guidelines for new and existing passenger ships (MSC.1/Circ.1533)and can effectively and efficiently plan the emergency evacuation path for cruise ship crowd.

In this paper, a framework of improved risk monitor system that integrates multiple applications of retrospective investigation analysis of risk factors, point-in-time risk monitoring and proactive risk management is presented. Among these applications capabilities, the plant configuration risk management is implemented and demonstrated with a safety injection system in the event of medium-break LOCA at nuclear power plants. The system reliability and safety analysis are conducted on the success-oriented logic models using GO-FLOW method. Both quantitative and qualitative risk measures addressed respectively by risk matrix and goal tree-success tree scheme with risk band display could provide global risk insights regarding plant configuration control.

This article discusses the possibility of verifying whether the formalism of Petri nets suitable for the optimization of transport systems. This work discusses the optimization of automotive traffic using the saturation flow method. The main aim of the article is to propose and validate a methodology for optimizing transport systems with saturation flow methods. There are discussed several optimization methods that are used for this purpose. The results of this search section were summarized and then a suitable model and an optimization method were chosen according to established criteria. Based on them we have proposed methodology that was verified pursuant to the application of the chosen procedures. One of Ostrava’s most interrupted crossroads was chosen as a model for optimization and simulation. Results of the experimental study are summarized in the conclusion. From the results of the experimental study, it can be stated that the static signaling model has been optimized in terms of time.

Different methods have been developed in the past to formulate and solve steady-state hydraulics of a water distribution system (WDS). The most widely used method nowadays is probably the global gradient algorithm (GGA). The loop-flow method (also known as the Q method) represents a viable alternative to GGA, especially when combined with suitably preprocessed network data. The main advantage of the Q method over the GGA is in the smaller number of unknowns to solve for, which is coming from the fact that real WDSs typically have far less loops than nodes. A new loop-flow-type method, relying on the novel triangulation based loops identification algorithm (TRIBAL) that was implemented in the corresponding new hydraulic solver (Q), is presented in this paper (TRIBAL-Q). The new method aims to exploit this advantage, while overcoming key drawbacks of existing Q methods. The performance of the TRIBAL-Q-based solver is compared with the GGA-based solver on four large real networks of different complexity and topology. The results obtained demonstrate that, despite requiring an increased number of iterations to converge, the TRIBAL-Q method-based solver is substantially computationally faster, has slightly better numerical stability, and is equally accurate in making predictions when compared with the GGA-based hydraulic solver.

Conventional cell-sized well arrays have advantages of high occupancy, simple operation, and low cost for capturing single-cells. However, they have insufficient space for including reagents required for cell treatment or analysis, which restricts the wide application of cell-sized well arrays as a single-cell research tool alone. Here, we present a novel dual-well array chip, which integrates capture-wells (20 μm in diameter) with reaction-wells (100 μm in diameter) and describe a flow method for convenient single-cell analysis requiring neither complicated infra-structure nor high expenditure, while enabling highly efficient single cell trapping (75.8%) with only 11.3% multi-cells. Briefly, the cells are first loaded into the dual-wells by gravity and then multi-cells in the reaction-wells are washed out by phosphate buffer saline. Next, biochemical reagents are loaded into reaction-wells using the scraping method and the chip is packed as a sandwich structure. We thereby successfully measured intracellular β-galactosidase activity of K562 cells at the single-cell level. We also used computational simulations to illustrate the working principle of dual-well structure and found out a relationship between the wall shear stress distribution and the aspect ratio of the dual-well array chip which provides theoretical guidance for designing multi-wells chip for convenient single-cell analysis. Our work produced the first dual-well chip that can simultaneously provide a high occupancy rate for single cells and sufficient space for reagents, as well as being low in cost and simple to operate. We believe that the feasibility and convenience of our method will enhance its use as a practical single-cell research tool.

Solution of the nonlinear system of equations describing the network hydraulics problem can be formulated in several different manners, yielding various methods of solution. The most popular formulation is probably the Global Gradient Algorithm (GGA). Loop-flow formulation is another method revisited by number of researchers in recent years. Loop-flow method has the smaller system matrix to solve, which is a benefit over the GGA’s matrix, coming from the fact that real networks typically have far less loops than nodes. However, need for cumbersome pre-processing to identify network loops and sparsity of solution matrix, which is highly dependent of implemented loop identification algorithm, remain key drawbacks of existing loop-flow methods. In addition, systematic testing on the real life networks of different topologies and complexities is still somewhat lacking in the literature. In this paper, new loop-flow type method based on the novel TRIangulation BAsed Loop identification algorithm (TRIBAL) coupled with efficient implementation of loop-flow based hydraulic solver (ΔQ) is presented. Performance of the new TRIBAL ΔQ method based solver is tested through the comparison with the reference GGA solver. Preliminary results show that significant calculation speedups can be achieved with proposed method, maintaining prediction accuracy and convergence of the reference solver. EPiC Series in Engineering

In the smart grid era, significant penetrations of distributed renewables not only directly impact the secondary low-voltage (LV) distribution network where they are connected, but also indirectly affect the primary medium-voltage (MV) distribution network. Therefore, load flow algorithms are expected to cover both MV and LV levels within a distribution network for more accurate and reasonable analyses. In this study, based on the Direct Load Flow approach and detailed modeling of common Dyn11 distribution transformers, a comprehensive three-phase load flow method which can effectively and efficiently solve the integrated MV and LV distribution networks is proposed. The feasibility and effectiveness as well as superior computational performance in terms of accuracy, efficiency and robustness are verified by simulations on the typical IEEE 4-bus test feeder and a real Australian distribution network over 24 hours.

Recently, the need for improving the efficiency of distribution network in terms of power losses is being emphasised. A large share of total power losses refers to low-voltage networks which are usually unbalanced. For the power flow analysis, it is necessary to use three-phase modelling. This study presents modelling of distribution network elements and their implementation in backward/forward sweep (BFS) power flow method. An improvement of the BFS method is developed by using the breadth-first search method for network renumbering and creation of modified incidence matrix. The improved method minimises the read elements of each iteration and results in a significant reduction in total calculation time without accuracy loss. This improvement makes this method more suitable for using in real-time calculations. The proposed method is used for calculation of power losses in unbalanced and symmetrical network which are compared. The purpose of this test is to show the advantage of a three-phase power flow analysis compared with a symmetrical model.

This chapter intends to simulate the current situation of Fiji Electricity Authority’s transmission network of Viti Levu by using the load flow method and investigate the situation of the overall system. The first part of the chapter focuses on finding out the problems faced by Fiji Electricity Authority with the reliability of the network. After inspecting regions vulnerable to faults, different scenarios have been tested in steady state with different loads in various parts of Viti Levu. Reaction of the network was observed to determine the highest load level that the network can support before collapsing. The second part of chapter proposes recommendations to improve the reliability of the network. These recommendations are tested using the ETAP software in the form of scenarios by incorporating different possible choices with the current network, and the results obtained from each scenario are analyzed. This chapter concludes with the listing of recommendations that can be made in order to do further analysis for future expansion of the network through renewable energy sources (RES).

In some massive constructions, like off-shore platforms for example, it is sometimes difficult or impossible to register the loading process during many years of exploitation. Knowing the input random processes characteristics, it sometimes seems promising to estimate the output characteristics using the structural dynamic equation. Following this approach, the spectral densities are employed into longevity estimation. Many methods for estimation of the fatigue damage thought the spectral densities were developed. The question arises: is it practical to use the spectral approach in case of post-processing when the process realization already exists? The aim of this paper is to show some limitations of the spectral approach. First, the short review with a brief analysis of the accuracy of the spectral method is presented. It is worth mentioning, that the ultimate goal of the authors of those methods is to achieve the results, similar to those, which were obtained from the rain-flow method. Next, the real loading process is analyzed. To show the fact, that some of the assumptions of spectral methods are doubtful, the method of the digitally modelled process is introduced. Pro and contras of the spectral methods are discussed.

This letter presents improvement in the revised current injection mismatch load flow method (NR-RCIM) using new representation of voltage controlled bus (PV bus). In the proposed formulation, the representations of PV buses are based on power mismatches and the other PQ buses based on current mismatches. This combined power and current injection mismatches method (NR-PCIM) decreases the required current injection load flow equations and improves the convergence performance in case of PV buses. Tests and comparisons among different Newton Raphson load flow techniques: conventional Newton Raphson (NR), NR-RCIM and the new NR-PCIM have been held to illustrate the validity and merits of the proposed algorithm.

This article provides a brief outline of continuous flow synthesis including the advantages of the flow method, serial combinatorial synthesis in flow, space integration of reactions, and reactions that cannot be done in batch to show that continuous flow synthesis will be a powerful and indispensable technology for pharmaceutical research and production.

In the paper, a model is firstly formulated for a pipeline network of variable connectivity in the terminology of graph theory. Through analyzing the topological changes of the pipeline network caused by connecting or disconnecting a pipe, several procedures are then proposed to construct the incidence matrix and fundamental circuit matrix of a graph directly from those of its parent graph or graphs without the time-consuming inversion of the corresponding incidence matrix. Thirdly, the proposed model and topological analysis procedures are used to establish a dynamic solver for a tank farm together with the chord flow method of Rahal (1995) [3]. Finally, the dynamic solver is applied to a tank farm of liquor for verifying the model and procedures proposed in this paper.

The paper describes a modified frequency computation method to calculate the optimal environmental flows. This method was used to design monthly environmental flows in Lancang river. The environmental flows calculated by the method are compared with those by the ecological flow method and the Tennant method, revealing its effectiveness.

The need for fast load flow algorithms for radial distribution networks that take advantage of their particular structure has been increasing for planning and optimization. In this article, a novel load flow method of radial distribution systems is presented. In the proposed method, different realistic loads have been considered, as loads are voltage dependent in distribution systems. The effect of load growth is investigated with the proposed method, as it is required for system expansion, planning, and operation. The proposed method has a good convergence pattern and execution time for all types of realistic loads and sizes of the networks. The efficacy of the proposed method is tested with different radial distribution systems and compared with other existing methods.

Working principle of net shape forging which utilizes flow relief axis or flow relief hole is newly proposed. Based on this principle, actual production of gear toothed components for automobile is successfully practiced. Because of the simplicity of the idea, wide range of practical applicability is expected.

The paper presents an analysis of different type of distribution generation (DG) unit impact on voltage profile and system losses of radial distribution network. Different types of DG have been considered viz. DG injects real power only, DG injects reactive power only, DG absorbs reactive power only, DG injects both real and reactive power and DG injects real power but absorbs reactive power. For calculation of different variable of interest, simple algebraic load flow method has been used by this paper. The analysis has been made on 12 node test system.

In this article, the authors present a novel algorithm for computing optic flow using a multi-agent based feature point tracking method. In this multi-agent based optic flow method, feature points which are invariant to scale, orientation and illumination changes are extracted and tracked in parallel using independent agents. Each agent is run by a separate light-weight thread which can be implemented using parallel processes on a multicore processor. The agents use a Kalman filter to predict the frame to frame position of the feature points in the image, producing position and velocity data for each feature point, which can then be used to perform optic flow, while simultaneously producing feature descriptors that can be used for object recognition and stereopsis. We show that in a parallel implementation, this algorithm provides significant performance advantages over other feature point tracking object recognition methods. It therefore may provide a plausible basis for a unified computer vision architecture including optic flow, object recognition, and stereopsis.

This paper gives the background and role of the market flow in market-based operating entity and describes the market flow methodology. It proposes that the market flow method calculates the same impact result on a flowgate as the unit dispatch system (UDS) flow and proves it mathematically. The equivalence of the market flow and the UDS flow shows that the UDS flow change on a constraint due to the UDS binding will have the same effect on the change in the market flow under the electricity market operations. It demonstrates the effectiveness of using the market flow in the congestion management process and coordinated management of transmission constraints. The numerical results on a 23-bus test system are also illustrated.

This paper evaluates the convergence of a load flow method based on Cespedes' formulation to distribution system steady-state analysis. The method is described and the closed-form of its convergence rate is deduced. Furthermore, convergence dependence of loading and the consequences of choosing particular initial estimates are verified mathematically. All mathematical results have been tested in numerical simulations, some of them presented in the paper.

Conventional load flow methods for transmission systems could not be utilized for distribution systems, due to their especial characteristics. If methods like Newton-Raphson and Fast-Decoupled are utilized in the case of distribution networks, probability of their convergence would be low. Therefore, due to inherent characteristics of distribution networks, it is essential to develop distribution version of load flow methods. Distribution networks usually have single source node and they have a radial configuration, but sometimes there are one or multiple Dispersed Generation (DG) units supplying a fraction of the distribution feeder loads. Unlike transmission systems, there might be some unbalanced loads along distribution networks. This paper presents a load flow method for unbalanced distribution networks, which can handle the presence of DG units on the distribution networks, in various operating modes.

The need of fast load flow algorithms for radial distribution networks that take advantage of their particular structure has been increasing for the planning and optimization. In this paper, a novel load flow method of radial distribution systems (RDSs) is presented. In the proposed method, different realistic loads have been considered, as loads are voltage dependent in distribution systems. The effect of load growth is investigated with the proposed method as it is required for system expansion, planning and operation. The proposed method has good convergence pattern and execution time for all type of realistic loads and size of the networks. The efficacy of the proposed method is tested with different RDS and compared with other existing methods.

Target tracking system has important application in military and civilian. In it, speed and accuracy are two important evaluations indicators. Harris algorithm is used to extract little part of target corner features which can improve this method’s speed. Then, the proposed method uses optic flow method which has high matching accuracy to match those extracted corner features in the following video frames. However, when the tracked target is rotated or transformation, the distributing of matched feature point is changed and target is easily lost. In order to overcome this shortcoming, bary algorithm is used to compute the bary of those matched features as displacement of target. It is proved by experiments that this method has not only high speed and tracking accuracy but also higher robustness to target rotation, transformation, shelter etc.

Based on image processing technology, this paper constructs a fabric-pilling evaluation system in which the edge flow method is used to implement pilling segmentation of complex fabrics. Then the system extracts three characteristic parameters: the number of pilling, total area of pilling and optical volume of pilling and describes the relationship between grades. Finally, in the three-dimensional space, the grade evaluation of fabric pilling is implemented by use of the least distance method. Experiments on various fabric-pilling images show that the system has extensive applicability and good result.