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This study presents a graphical method - genetic algorithm (GMGA) approach which combines graphical method (GM) and genetic algorithm (GA) for the parameter estimation of twofold Weibull mixture model. GM is firstly conducted to obtain crude estimates based on which the searching domain of each parameter is constructed to prevent the subsequent GA process from local convergence. Then GA searches the optimal parameter estimates according to the fitness function, which is a measurement of the absolute residuals between the fitted and the empirical distribution functions. The fitness function is developed through modifying the Kolmogorov-Smirnov (K-S) test so that it can also be directly used as a criterion of goodness-of-fit test. A numerical example is provided to verify the effectiveness of GMGA. The results show that the parameter estimates obtained by GMGA are more accurate than by some existing approaches.

Based on the rafts observation of 26 high-rise buildings in Vietnam and around the world, it is recorded that they are very thick. So, the questions is, what is the role of raft (and its thickness) in a foundation system individually, and the interactions between raft-soil and pile in the whole upper structure in general? And why do rafts in some buildings seem to be very thick? For example, MesseTurm Tower is 256 meters tall with raft's thickness of 6.0 meters while the others are relatively thinner such as Dubai Tower is 400 meters tall with raft's thickness of 2.5 meters. A literary review and a parametric study on the factors affecting raft thickness shows that it depends on the number of floors, pile system's properties and Young modulus of soil. Based on the mentioned observation, a graphical method is, therefore developed. The method is then verified and calibrated into six case studies equivalent to six buildings constructed in Vietnam and around the world. The estimated raft thicknesses from the 26 mentioned cases using the graphical method are reasonable in comparison with designed ones. Thanks to that, they can explain the cases of thick or thin rafts.

Systems Engineering is evolving from a largely text-based endeavour towards a more graphical and model-based approach. However, there is little agreement on the underlying concepts and processes used in systems engineering and their representation in models. This paper proposes a requirements modelling approach based on a reduced set of underlying concepts, which can readily be given a graphical representation. We then show how a graph isomorphism could be used to transform from the requirements space into the design space. At the same time we review the ability of current models to represent the key concepts and transformations.

In electrical power systems, coordination and selectivity of protection devices are extremely important so that when a disturbance or defect occurs in the system must have a actuation of the protection, isolating the defect from the rest of the system. The objective of this paper is to evaluate the coordination of overcurrent relays using graphical method in an interactive platform, this simulation environment allows the visualization of the various actuation curves used by several relay manufacturers. The graphical method was implemented in Matlab Graphical User Interface (GUI) a graphical programming interface containing curves of several standardizations, being able to adjust the slopes of inverse-time curves and adjustment parameters of the instantaneous and timed overcurrent functions, generating a coordination diagram. Results are presented through test cases show that the proposed methodology is effective in coordination relays problems.

Test engineers are often faced with the challenge of selecting test cases that maximize the chance of discovering faults while working within a limited budget. Combinatorial testing is an effective test case selection strategy to address this challenge. The basic idea is to select test cases that ensure that all possible combinations of settings from two (or more) inputs are accounted for, regardless of which subset of inputs are selected. This is accomplished by using a covering array as the test case selection mechanism. However, for any given testing scenario, there are usually several alternative covering arrays that may satisfy budgetary and coverage requirements. Unfortunately, it is often unclear how to choose from these alternatives. Practitioners often want a way to explore how the input space is being covered to decide which alternative is best suited for the testing scenario. In this paper we propose a graphical method that may be used to evaluate binary covering arrays. The method allows practitioners to visualize input space coverage for inputs of interest. We illustrate the method with several examples.

Graphical methods (GM), based on analysing data derived from tracer passages, are robust tool used to estimate the descriptive parameters related to a microvasculature. These parameters known as: fractional plasma volume (vp), transfer constant (Ktrans), total distribution volume (vD). This study examines the time frame at which these methods can produce more accurate results. To do so sets of uptake tissue curves (Ct) were simulated by using approximation to the tissue homogeneity model (AATH) and the arterial input function (Cp) is constructed by adding three Gamma-variant. The tissue uptake curve is divided into five time frames, as follows: initial time to AIF's peak [t0,tp], AIF's peak to AIF's first pass [tp,tfp], first time passage [to, tfp], at equilibrium teq, initial time to equilibrium [t0, teq], and initial time to washout time [t0, tf] The study revealed that care should be taken in using GM during the bolus passages; more accurate Ktrans estimates can be determined more accurately from the initial data obtained from the first passage of the bolus within the time frames [t0, tp] and [tp, tfp]. Contrary to expectation, the unidirectional model decline to measure vp. On the other hand, the bidirectional is success to estimate vD more accurately within the time frame [tfp, tf].

A graphical method for the preliminary design of phased array antennas is proposed. Despite its simplicity the proposed technique results computationally efficient and allows to estimate both the number of elements and their mutual distance, taking into account constraints on the side lobe level, the bandwidth and the beamwidth requirements.

With the increasing number of urban vehicles, traffic congestion is becoming more and more serious. Bidirectional green-wave coordinated control is one of the main ways to alleviate the city traffic congestion and improve the efficiency of city traffic. In this paper, a bidirectional green-wave control method based on random optimal graphic method is proposed. According to the different capacity of the road in both directions, the formula of bandwidth proration coefficient is established, and the green-wave bandwidth is allocated reasonably. The target formula of bidirectional green-wave and the target formula of the bidirectional additional bandwidth of the key intersection are used to find the suitable bidirectional green-wave band. The effectiveness of the method is evaluated using on an arterial road simulated by the VISSIM simulation software, and compared with the traditional graphic method. The simulation results show that the capacity of the optimized arterial road is improved effectively compared with the traditional graphic method.

This paper proposed a method for constructing the graphic modeling system on the basis of Visio drawing control through a lot of research about the technology of testable modeling and analysis. A regional growth algorithm based on the idea of image segmentation is put forward to obtain the fault-test dependency matrix and corresponding testability indicators such as fault detection rate(FDR) and fault isolation rate(FIR) are calculated according to the matrix. The optimal decision tree is also generated in this paper using AO∗ algorithm, which provides effective and reliable guidance for fault isolation. At last, the functions of the testability modeling and analyzing are verified taking a tape player as the research object. The experiment results show that the scheme is feasible and has important reference value for developing testability analysis tools.

A graphical method for a two-input two-output (TITO) system to compute all feasible stable region is proposed in this paper. It is the first time the stability region of the internal model controller parameters is given in the parameter space for multivariable system. The internal model controller can be designed by effective open-loop transfer function (EOTF). Next, the parameter space is divided into stable and unstable regions. Finally, the example is presented to demonstrate the validity of the proposed method.

Complex robotic systems like the DLR Hand Arm System integrates a huge amount of sensors and actuators. Hence system design and especially communication infrastructure design has to be flexible in a heterogeneous network of different bus systems. As basis, a modular electronic concept as well as a well-structured communication concept is necessary [1]-[3]. SpaceWire suites well to these requirements since on one hand it supports arbitrary topologies from point to point up complex network structures and on the other hand it is easy to implement and has a small footprint. Additionally its logical and regional addressing scheme enables changes in the topology during runtime simply by reprogramming the routing switches. However, such changes require expert knowledge. This work presents a graphical method to setup and configure SpaceWire network topologies. This enables non-experts to replace or integrate new components to the system or to set up a test bed to investigate a specific aspect. The developer provides a GraphML description [4] specifying the SpaceWire communication capabilities of each component. Thus the user is able to adapt the SpaceWire network topology or to set up a new one simply by merging the different GraphML descriptions of the used components. A post process is afterwards used to analyze the GraphML description and to generate the necessary configuration messages according to the topology. This enables faster development cycles and rapid prototyping. The approach is approved and explained using the SpaceWire network topology of the DLR Hand Arm System.

Refractive index of the substrate depending on its absorption is used in the graphical method for optical characterization of a film on a transmitting substrate, from its transmission spectrum. Three amorphous chalcogenide films on identical glass substrates are characterized by the graphical method. Indications are presented that these characterizations are more accurate than previous characterizations of the same films.

Minimum intake and exhaust flow resistance you need to get to build a high-performnace engine. If all these facets are optimized and we add high RPM the result is high output.

Wind power resources are abundant in India; as a result the wind power industry has entered a period of rapid growth, and has been facing new challenges currently. Wind power is environment friendly and renewable in nature. The wind is caused by an air in motion and is produced by the uneven heating of the earth's surface by the sun. The wind speed has been one of the most significant parameter in the design and investigation of wind energy conversion systems (WECS). The objective of the present research paper is to assess the feasibility of wind power generation for a new site in Himachal Pradesh using micro-turbines. The major contribution of this paper, envisages two parameters, i.e., shape and scale parameter based Weibull distribution model for investigating wind speed variations and Weibull parameters calculation by Least Squares Fit Method (LSM) also known as Linear regression model using graphical method. This research work shows that the hilly site of Hamirpur in Himachal Pradesh has good wind power potential and large magnitude of winds have been available for power generation during the months of March to June suitable for low wind power generation.

This paper presents a new two-direction green wave optimization method to solve the coordination control problem of urban arterial traffic. An optimization method based on MATLAB graphical computation was proposed to solve the synchronous optimization for five parameters including the phase, the phase sequence, the offset, the cycle time and the split. Inbound coordination in the heavy traffic flow direction was achieved firstly, and the offset between each intersection in the outbound direction was adjusted by using phases with asymmetric signal mode, lag-open or advanced-close and etc. Then the coordinated control scheme for multi-plan was designed flexibly according to the characteristics of different intersections. The implementation shows: this method can take into account the non-motor vehicles, pedestrian and intersection traffic demands, improve the traffic efficiency for arterial roads, and reduce vehicle stop delay.

A graphical method for identifying positive feedback loops in analog circuits is presented for the purpose of identifying the stable equilibrium points. Graphical models for key analog components are developed and hierarchically used to obtain a graphical representation of an analog circuit. From this graphical circuit representation, positive feedback loops are defined. Applications to identifying Trojan operating states and trust in electronic circuits are discussed.

This paper proposed a method to calculate the operating point of photovoltaic (PV) generation system under shading effect. To simplify the algorithm, the graphical method is used in this research. The PV modules in each string are divided in to two group, i.e. shaded and unshaded groups. In addition, the double diode model with Bypass diode is proposed in this paper. This model is used to investigate the output characteristic, i.e. current, voltage, and power. The characteristic given from the PV model is used to plot the I-V and P-V graph for each PV group. The characteristic of each group is combined together to obtain the characteristic of the whole string. The graphical method is used to specify any peak power that occurs under shading effect. The result shows that the proposed method can determine the operating point of PV system when shading effect occurs without optimization.

This paper presents a graphical method used for Fault Detection and Isolation (FDI) of hybrid dynamic systems. The developed method is based on the notion of Global Analytical Redundancy Relations (GARRs) from the hybrid bond graph model, which describes the system behavior at all of its operating modes. We use a hybrid tank system to illustrate the concept of the GARR.

A new technique is presented to design proportional-derivative (PD) controller for integrator plus dead time (IPDT) processes. For developing this technique a graphical approach is used. More precisely speaking, five loci are established and plotted in the controller parameters plane, so that on each locus a performance index such as stability margins and crossover frequencies to be constant. Then it is assumed that the characteristics of the desired feedback system are stated in the form of two of these loci. After that by sketching the two under considering loci the intersecting point of them is obtained and hence the values of the controller coefficients are determined. The proposed method is illustrated by an example.

This paper describes a graphical method for the optimization of Quadrature Voltage Controlled Oscillators (QVCOs) based on the coupling of two LC-tank VCO. A three-dimensional phase noise analysis diagram and graphical optimization approach is presented, to optimize QVCO phase noise while satisfying design constraints such as power dissipation, tank amplitude, tuning range and start up condition. The obtained QVCO can be tuned between 2.2GHz and 2.58GHz, and shows a phase noise of −129 dBc/Hz at 1MHz offset from a 2.4 GHz carrier, for a current consumption of 9.25mW. The equivalent phase error and amplitude error between I and Q signals are respectively 0.65° and 1.87%.

Based on the selected chemical and physical properties of amino acids, a dynamic 3-D graphical representation of protein sequences is outlined. We introduce the numerical characterization of protein graphs as descriptors to analyze and compare the nine ND5 proteins, and the results consist with the known fact of evolution. The graph of protein sequences have good visibility, the approach is simple, convenient, and fast.

This paper presents a graphical method for safety assessment of grounding systems. For a grounding system to be safe, the maximum touch and step voltages should not exceed postulated safety criteria. The method presented in this paper is applicable to the safety criteria of the IEEE Standard 80 as well as the IEC-479-1. Both standards define safety criteria in terms of allowable body current. The allowable body current is then translated into the allowable touch and step voltages. Thus, safety assessment of a grounding system is referred to a procedure by which the actual maximum touch and step voltages are computed and compared to the maximum allowable (safe) touch and step voltages. Since the IEC-479-1 safety criteria are nonlinear, a graphical method is presented for safety assessment.