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Crystallography is the study of the configuration and properties of a crystalline state. With the aid of mathematical approach, the crystal can be classified into different types of space groups, one of which is called the Bieberbach group. A mathematical approach has been used to solve problems regarding crystal properties and can provide a piece of information on the group structure such as the homological invariant. In computing the algebraic properties of a group, the group must first be transformed into a polycyclic presentation, such that the presentation consists of generators that describe the group. Based on the polycyclic presentation, the computation of the derived subgroup, G', is done to further explicate the homological invariants. The computation of G' is vital as it will be used to satisfy several definitions, theorems, and propositions in explicating the homological invariants of a group such as the nonabelian tensor square. The derived subgroup is written in the form of commutator. It is found that the derived subgroup for the second Bieberbach group of dimension six with the quaternion point group of order eight consists of 72 commutators in which 42 of the commutators are the identity elements, and it is further simplified to only consisting of 5 commutators. [ABSTRACT FROM AUTHOR]

Power delivering capabilities and the number of loads connected to the power supplies are increased due to the development of new devices through technological advancement. Many industrial and domestic applications require a power converter which has the ability and functionality to convert the single input voltage level to multiple output voltage levels, so that it can drive many DC loads like Laptops, Switched Mode Power Supplies, DC Drives, accessories in electric vehicle (EV), This paper proposes one such power converter namely non-isolated boost converter, which has a single input (12V) and two outputs (48V and 24V). It uses only two switches for two outputs thereby reducing the component count and hence the cost of the converter is reduced. Current Mode Control (CMC) Scheme employed here uses two Proportional Integral (PI) controllers such as outer voltage controller and inner current controller respectively. Closed loop simulation is carried out using Matlab/Simulink software tool. It is inferred from the simulation results that the output voltages are well regulated for line, load and set point variations. [ABSTRACT FROM AUTHOR]

In the current study, utilizing the (λ μ) contraction condition, we proposed a new end point result for set valued functions in bipolar metric space. The continuity and commutativity of mappings are not used to prove this theorem. The example has been provided to support the conclusion. The many previous results from the literature are extended, improved, and modified in this paper. [ABSTRACT FROM AUTHOR]

We present how to profitably approximate swimming trajectories leveraging Radial Basis Functions (RBFs). The data of these trajectories were obtained by recording athletes of the Deaf Olympic Italian National Team while swimming. In particular, collected videos were processed by U-NET, a deep learning model architecture, resulting in some sets of two-coordinates points of virtual targets. The obtained sets of points describe trajectories that are approximated with RBFs. [ABSTRACT FROM AUTHOR]

In the conventional turning process, a lathe is operated manually by an operator with special skills. The manual operation has several weaknesses i.e. the quality of the product depends on the skill of the operator, the measurement accuracy is less accurate, need a long time to set the machine, the cutting rate depends on the operator's experience, and the quality of the surface product must be checked regularly. To overcome these weaknesses, it is necessary to have such a control system to optimize the feed rate on a lathe by considering allowable cutting force and other machining limitations. For this reason, this study focused on the detection and control of cutting forces on lathes using a fuzzy logic controller. This research was conducted by modifying a variable speed bench lathe. The feed rotary on the lathe was replaced with a stepper motor so that the feed motion could be carried out automatically. A load cell is attached to the tool post to detect cutting force during machining time. The program for adjusting the feed rate and detecting cutting force is created based on the fuzzy logic controller method. The sensor's cutting force read was used as a value to adjust the feed rate. The result shows that the overall cutting force has been successfully controlled at set point 2.55 N and the delay time output also followed the trend of cutting force input. [ABSTRACT FROM AUTHOR]

Building occupants are known to be affected by Indoor Environmental Quality (IEQ). Maintaining IEQ quality can provide comfort, reduce disease occurrence, and increase occupant productivity. Natural Lighting, Natural Ventilation, and Mechanical Ventilation are the three parameters that influence the quality of indoor environment. These three parameters are subdivided further into several factors that determine Indoor Environmental Quality. Using a meta-analysis and content analysis, this study seeks to identify the contributing factors that influence the improvement of Indoor Environmental Quality. Using keywords related to IEQ, ten literatures and twelve factors related to IEQ improvement are obtained. There are five factors related to natural lighting, five factors related to natural ventilation, and two factors related to mechanical ventilation. The analysis results show that Building Orientation, Window to Wall Ratio, Window Opening and Ventilation, and Operating Temperature Set Point are the most frequently mentioned factors in IEQ improvement in the literature reviewed. [ABSTRACT FROM AUTHOR]

Second-order unstable processes are frequently encountered in process industries. The higher-order process dynamics are approximated to second-order processes in order to design a controller. In industrial processes, Proportional Integral Deriva-tive(PID) controllers are still widely used controllers. PID, cascaded with filters provides satisfactory closed-loop performance for unstable processes. The present work proposes a PID controller cascaded with a fourth-order filter for an unstable Second Order Process with Time Delay(SOPTD). A polynomial approach is used to estimate the controller and filter parameters analytically. For the time delay approximation, a higher-order Laguerre shift is utilized. The Maximum Sensitivity(MS) criterion is used in order to calculate the tuning parameter(λ). To reduce servo response overshoots, a set point filter is chosen. The present method is compared with other reported methods using various performance indices. [ABSTRACT FROM AUTHOR]

The present paper aims at the design of a Proportional-Integral-Derivative(PID) with a fourth-order filter for controlling Second Order Process with Time Delay (SOPTD). The PID and fourth-order filter parameters are obtained analytically using the polynomial approach. The selection of the sole tuning parameter (λ) depends on Maximum Sensitivity (MS) criteria. As it is inevitable to adopt approximation of time delay in the process of deriving unknown controller parameters, a higher-order approximation of time delay i.e second order Pade's shift is used to ensure more accuracy relatively with the existing methodologies. The controller introduces zeros in the overall transfer function of close loop control system. These zeros may result in overshoot in the response. In order to bring down this overshoot, a set point filter is employed. The proposed method is compared to other existing techniques and the performance evaluation is presented in terms of various performance indices. The proposed method is also validated on a real-time process i.e a DC servo motor. The relation between speed and voltage of DC servo motor is obtained with the help of input out put data. The proposed method is then utilised to derive the controller parameters. [ABSTRACT FROM AUTHOR]

The need for energy has become a primary need and requires the stability of electrical energy generation. In a wind turbine system, a special control is needed to keep the turbine rotation at a certain limit. However, in reality, load conditions often fluctuate due to an increase or decrease in load. Therefore, the purpose of this research is to design an ANFIS controller to control blade pitch angel with adaptive changes in wind speed and load dynamics, and the testing is done through simulation on Simulink/MATLAB. The controller works to adjust the blade angle when the generator speed exceeds/less than the set point value due to changes in wind turbine speed and load dynamics. By adjusting the rotor speed of the generator, the output power delivered can be balanced with the use of the load, which is indicated by the output frequency value being stable at 50 Hz. From the ANFIS controller testing process through simulation, it can be concluded that the ANFIS controller generator can maintain the output frequency with load dynamics due to the presence of a more controlled pitch angle control than the Fuzzy-PID controller by decreasing up to 1,454% overshoot and 6,26s settling time. [ABSTRACT FROM AUTHOR]

In the work, we investigate fixed points and invariant sets of quadratic Lotka–Volterra mappings acting in a finite-dimensional simplex. Lotka–Volterra quadratic mappings are remarkable for their "abundance" of fixed points (for example, all vertices of a simplex are fixed points), and therefore they are interesting for study. It is known that isolated fixed points have an odd number of nonzero coordinates, and considering these fixed points to be isolated, we give an algorithm for finding fixed points in addition to the vertices of the simplex that belong to the faces. In the paper, we prove the existence of invariant curves connecting a certain pair of fixed points, which consist entirely of fixed points. And also we prove that there is an invariant plane passing through fixed points belonging to strong faces. [ABSTRACT FROM AUTHOR]

In this paper, we interpolate data points by General Hybrid Trigonometric (GHT) Bezier curve. GHT-Bezier curve contains four free parameters to allow curve flexibility. By determining control points on the GHT-Bezier curve based on a certain degree, we interpolate the curve that pass through the data points. We use uniform parameterization method on GHT-B curves. Firstly, we discussed the uniform parameterization of GHT-Bezier curve. Then we demonstrate the parametrization method on few sets of data points. We observed the curvatures of the parametrized curves for selected different values of free parameters in GHT-Bezier curve. [ABSTRACT FROM AUTHOR]

The aim of this research is divided into two main parts, the first is to find new concepts to limit points based on the concept of focal set defined in i-TPS, where we called the first type strips point and the second type redirect point, and we have highlighted in this research the most important properties and the connection between them. The second goal is to define new types of dens sets through these points. Dense sets have importance in applied mathematics, to be a new pivot that solves some problems that can only be solved by using dense sets [ABSTRACT FROM AUTHOR]

The planning or scheduling process is one important factor in determining the success of a project. If project scheduling is done properly, the probability of success of a project will be even greater because scheduling is an important element in project success. Therefore, it is necessary to optimize the project so that it can be seen how long a project can be completed and look for the possibility of accelerating the project implementation time with the project objectives can be completed on time and at an economical cost. Applying the critical path method (CPM) in the project schedule is expected to produce a time schedule with the right duration of work and a high probability of success. Making a network diagram is needed to determine the interrelationships between activities so that the critical path of the lintel set point project will be identified. The concept of cost slope is applied by considering the existence of normal costs and acceleration costs to determine project optimization. From the data processing results, this project can normally be carried out with a duration of 171 days and requires a cost of IDR 431,185,000. Applying the CPM method gets the optimal solution where the project can be done in 155 days with a project cost of IDR 429,171,000. [ABSTRACT FROM AUTHOR]

Allow G being a strict chart with point setV & line set E. The mapping g :V(G)→{0,1} of one-to-one & onto labeling produced a line-labeling g : E(G)→{0,1}explained by g *(uv) = |g(u) − g(v)| for evey lines uv ∈ E(G). Letting Vg (i) to be the point set V of G along with g(v) = i & Eg(i) to be the line setuv along with g *(uv) = i. The cardinalities of Vg (0),Vg (1), Eg (0) and Eg (1) are symbolized by vg (0),vg (1),eg (0) and eg (1) orderly. If these two conditions, |vg (0) − vg (1)|≤1&|eg (0) − eg (1)≤1 are satisfied in graph G then it is termed as cordial labeling & graphs carrying that particular labeling is called Cordial graphs. Here in this article, we look into cordial labeling of join and composition of some graphs. [ABSTRACT FROM AUTHOR]

This paper makes a comparative analysis of efficiency improvement of Brushless DC (BLDC) motors in motoring mode by controlling varying load conditions. Proportional integral (PI) controller and proportional integral derivative (PID) controllers are implemented to improve efficiency of BLDC motors. Sample size has been calculated using G power software and it is determined that each algorithm requires 20 samples and totally 40 sample tests have been carried out. Based on the results obtained it is inferred that the PID controller provides better Efficiency 61% compared to PI controller 57% for a set point of 1500 RPM and The 95% confidence intervals are derived using a P value of 0.05, which is deemed statistically significant. PID controller provides better efficiency improvement compared to PI controller for selected data set. [ABSTRACT FROM AUTHOR]

This paper makes a comparative analysis of Efficiency improvement of Brushless DC (BLDC) motors in generating mode by controlling the varying load conditions. Materials & Methods: Proportional integral (PI) controller and proportional integral derivative (PID) controllers are implemented to improve efficiency of BLDC motors. The sample size is calculated to be 40 for two groups. Results: Based on the results obtained it is inferred that the PID controller provides better Efficiency 82% compared to PI controller 78% for a set point of 1500 RPM and P value is <0.05 considered to be statistically significant and 95% confidence intervals are calculated. Conclusion: PID controller provides better efficiency improvement compared to PI controller for selected data set. [ABSTRACT FROM AUTHOR]

The vibrational Raman and IR spectroscopic activities of molecules depend on their responses to the perturbation of light radiation upon them. These responses in turn are determined by the geometrical structures of the molecules that have been classified into different types of point group symmetries. By using group theoretical methods, the analysis of the vibrational spectroscopic activities can be done without making the full calculation on the probability amplitude integral for simple molecules. Molecules with D3h, D4h, and D5h point group symmetries had been chosen in this work to show how this group theoretical method analysis work. [ABSTRACT FROM AUTHOR]

Both boundary points and boundary sets are important topological concepts that have wide resonance and influence in applied mathematics, especially in metric spaces which have drawn researchers to them. Hence, we highlight the construction of new type of boundary points and boundary sets in i-topological proximity space and highlight the most important possible properties of them and their relationship of them. [ABSTRACT FROM AUTHOR]

The basic idea of this article is to confine an Inverse Eccentric fuzzy graph(IEF(G)) with a membership function on the point set and line set of IEF(G) and to establish IEF(G) using these functions. Further, determined the degree of a point set for an Inverse Eccentric Fuzzy Graph. Also Characterised by limitations on the order and size of the inverse eccentric fuzzy graph. Theoretims relating to the point membership function on subgraphs and spanning subgraphs of an Inverse Eccentric Fuzzy Graph are discussed. [ABSTRACT FROM AUTHOR]

Python Programming is emerging as a great computational tool in the field of mathematics. In this paper, we particularly discuss the application of the python programming language to generate the limit points and the derived set for each subset of a given set in a topological space. For this, we make use of the different compound data types available in python including the dictionary, list and also the set operations. This variety of data types and numerous math functions in python allows the user to compute coding to solve extensive problems within a short span of time. It also provides the platform to explicitly convert one data type to another making it more convenient to code. One must be well versed with the concept of neighborhood in analysis as knowing the neighborhood of each point of a subset is essential to find the limit point of a subset and those limit points when collected, leave us with the derived set. Thus, we would also be eventually focusing on gathering the neighborhood of each point of a subset and then finding the limit points for each subset, which will lead us to the final step of computing the derived set. [ABSTRACT FROM AUTHOR]

The concepts of associated soft point subset for a soft subset and associated soft subset for a subset of the set of all soft points are presented in this work. Moreover, a Galois connection is established between the complete lattice of all soft subsets of a soft set and the power set (which is a complete lattice) of the set of all soft points of the soft set. [ABSTRACT FROM AUTHOR]

In the research domain of Mathematics, Topology plays a major role as it is all about studying the surfaces or the region. It deals with the objects that retain their properties irrespective of continuously changing their shape but without adding any additional substance over them or without making any additional hole in them. In point set topology, for any set, if some of its subsets are collected in such a way that it possesses three specific conditions, then such a collection will be known as the topology for that set. Though it sounds simple, practically it turns hectic to frame such collections when the cardinality (n) of the set is large. For instance, for any set with n=3, one can frame 29 distinct topologies. But all of a sudden, when n=4, the total number of possible topologies raise to 355. Thus, arriving at such a collection with more subsets satisfying the topological axioms turns highly complicated. To overcome this issue, in this paper, we have developed a Python program which will act as the Topology Generator. Irrespective of the cardinality of the set, this coding will function effectively such that as and when the topologists are in need of making use of a topology with a larger number of subsets in it, it won't be hectic any more. In that way, this program might be helpful for larger range of audience starting from the students who are undergoing their masters up to the eminent researchers in the field of topology. [ABSTRACT FROM AUTHOR]

A system with self-organized criticality in a randomly moving environment is studied with field theoretic renormalization group analysis. The system is described by the anisotropic model of a "running sandpile" (continuous stochastic equation) introduced by Hwa and Kardar in [Phys. Rev. Lett.62: 1813 (1989)]. Moving environment is modelled by the Navier-Stokes equation for a randomly stirred incompressible fluid. We find a system of β-functions whose zeroes (being coordinates of fixed points of renormalization group equation) determine universality classes – regimes of critical behavior. It turns out that at most realistic values of the spatial dimension d = 2 and d = 3 there exists universality class of the pure advection by randomly moving environment (i.e., of a passively advected scalar field). Thus, isotropic motion renders both the nonlinearity of the Hwa-Kardar model and its anisotropy marginal (or irrelevant) for long-time large-distance behavior. Practical calculations are performed to the first order of the expansion in small parameter ε (one-loop approximation). [ABSTRACT FROM AUTHOR]

We consider the problem of finding the sizes of the largest and the least caps in projective geometry PG(n, 3) over the field F3={0, 1, 2}. A cap is a set of points, no three of which are collinear. We give two new recurrence constructions for complete caps in projective geometry PG(n, 3). Notice that the constructed caps for some n′s have maximal possible sizes. [ABSTRACT FROM AUTHOR]

Point Set Registration (PSR) algorithms have very different underlying theoretical models to define a process that calculates the alignment solution between two point clouds. The selection of a particular PSR algorithm can be based on the efficiency (time to compute the alignment) and accuracy (a measure of error using the estimated alignment). In our specific context, previous work used a CPD algorithm to detect and quantify change in spatiotemporal datasets composed of moving and shape-changing objects represented by a sequence of time stamped 2D polygon boundaries. Though the results were promising, we question if the selection of a particular PSR algorithm influences the results of detection and quantification of change. In this work we review and compare several PSR algorithms, characterize test datasets and used metrics, and perform tests for the selected datasets. The results show pyCPD and cyCPD implementations of CPD to be good alternatives and that BCPD can have potential to be yet another alternative. The results also show that detection and quantification accuracy change for some of the tested PSR implementations. [ABSTRACT FROM AUTHOR]

We present mathematical remarks and comments on the 1D conformal mechanics of de Alfaro-Fubini-Furlan, the isotropic oscillator driven by the conformal mode, and the Galajinsky variant of Schwarzian mechanics. We discuss their relation with the Ermakov-Pinney Equation and the Kummer-Schwarz equation as well as their Lie point symmetry groups. [ABSTRACT FROM AUTHOR]

This article discusses a security analysis provided by blockchain technology. The importance of distributed ledger when communicating in equitable distributed networks. This situation can be expressed in the abstract from the point of view of a group of generals from the Byzantine army, stationed at a camp with their troops around an enemy fortress. By communicating only through communications, the generals must agree on a common battle plan. However, one or more of them can be traitors who will try to confuse others. Mathematically, the algorithm is proven to ensure that loyal generals reach an agreement. The byzantine generals' problem is analysed, Byzantine fault tolerance (BFT) and Byzantine agreement problem. Mathematically, the theorem of reaching consensus with M number of compromised nodes is demonstrated while maintaining an acceptable level of Byzantine fault tolerance (BFT).The results of the article can be used practically when constructing a blockchain for exchange of messages in VANET, also in the MQTT data transfer protocol in IoT. [ABSTRACT FROM AUTHOR]

Process Automation Systems are widely known to be a crucial element in processing plants worldwide. In an environment that is ever-changing, process automation is applied in industries when possible to mitigate complexities with advance process control (APC) systems specifically leading to higher efficiency, less operator interaction and increased profits. APC is a proven control and optimization technology delivering measurable and sustainable improvements in production yield, coupled with the added value of energy savings. Many researches focused on modelling the Ethylene glycol (EG) production process each with distinct reactors and reactions. On the other hand, the advances on its control system were poor. Thus, this research fills the gap on the implementation of APC for the EG reactor. In this work, a linear based model predictive control (LMPC) is developed and implemented in EG reactor. The aim of LMPC is to control the production rate and reactor temperature for an optimized hydrogenation reactor. The optimal set point used is based on multi-objective optimization approach using £-constraint method. A state-space model is used in the prediction control is constructed with the best fit of 91.51% and 83.34% for EG production rate and reactor temperature, respectively. The LMPC is developed in Simulink and tuned via the MPC design toolbox in Matlab. The LMPC performance was evaluated based on the analyses results obtained from set point tracking, disturbance rejection and robustness test. The results showed that the LMPC can operate efficiently under tight boundary constraint. This sums up that the LMPC can control both control variables under strict boundary conditions. [ABSTRACT FROM AUTHOR]

This paper addresses the detection of 3D hand pointing direction from RGB-D data by a mobile robot. Considering ubiquitous forms of pointing gestures, the 3D pointing direction is assumed to be inferable from hand data only. First, a novel sequential network-based learning model is developed for the simultaneous detection of hands and humans in RGB data. Differing from previous work, its performance is shown to be both accurate and fast. Following, a new geometric method for estimating the 3D pointing direction from depth data of the detected hand is presented along with a mathematical analysis of sensor noise sensitivity. Two new data sets for pointing gesture classification and continuous 3D pointing direction with varying proximity, arm pose and background are presented. As there are no such data sets to the best of our knowledge, both will be publicly available. Differing from previous work, the robot is able to estimate the 3D hand direction both accurately and fast regardless of hand proximity, background variability or the detectability of specific human parts - as demonstrated by end-to-end experimental results. [ABSTRACT FROM AUTHOR]

The article constitutes the outlines capture of the digital Arabic character images which is appropriate for non-Roman (Arabic) fonts. The external boundaries of Arabic font character (ع) have been traced and boundaries of holes of a specific Arabic characters such as (و), the three interpolated curves of the Arabic character (ه). For (ك) character trace parent (ل) and their child (ء) and (..) in Arabic character ((ي) were outlined by the modification of Jacobs stopping criteria along with the tracing Moore-Neighbor algorithm. Moreover, a new algorithm has been presented using picewise cubic Hermite spline interpolation (PCHIP) to process the margins of characters and shapes. This algorithm is significant in computer graphics. Sample plots have been included to illustrate the power, effictiveness and flexiblility of this algorithm. Hermite spline algorithm is more suitable for few nodes on the outline of characters or shapes. The modified algorithm can be categorized in terms, types: capture a given set of data points. [ABSTRACT FROM AUTHOR]

This article demonstrates the improvement of control performance in formaldehyde production process using model predictive control (MPC) in comparison between conventional proportional-integral control. MPC is an advance process control which can improve the performance of a control process in terms of time delay, open loop instability, constraints, and thereof combinations. MPC will reduce the variance in the control variable that affects the process to operate closer to physical constraints. The empirical model of the MPC controller is based on the process reaction curve (PRC) by using the first order plus dead time (FOPDT) approach. Four controllers which were flow control (FIC-102), temperature control (TIC-101), pressurce control (PIC-101), and liquid level control (LIC-101) were tested by changing the set points (SP) and giving disturbances. The performance indicator for the controllers are shown by their value of integral of absolute error (IAE) and integral of square error (ISE). The results show that the MPC improved the controllers' performance either tested by changing SP or giving disturbance and are better in terms of IAE or ISE. [ABSTRACT FROM AUTHOR]

In this paper, we introduce the notion of c-cover for the associated L-fuzzy point set of an L-fuzzy set and it is shown that the set of all c-covers o f t he associated L-fuzzy point se t is a pa rtially ordered se t. Fu rther, we es tablish a connection, which is both a Galois connection and a Lagois connection, between the poset of all L-fuzzy i-covers of an L- fuzzy set and the poset of all c-covers of the associated L-fuzzy point set. [ABSTRACT FROM AUTHOR]

Ocean acidification is one of the phenomena caused by climate change in the world. Most Ocean acidification (OA) experimental is carried out in a laboratory by creating a simple system. In this research, the seawater in tank is given CO2 gas regulated using a needle valve driven by stepper motors using Proportional-Integral-Derivative (PID) controller. This tank is equipped with a stirrer to accelerate the system's homogeneity, flow sensor, and pH sensor. Arduino as a system control is tasked to regulate stepper motors, reading and keeping the pH value according to the set point value while recording the changes of pH value occurring in the tank. This research shows that the system can reach a desired set point and maintain it with 1.7 % overshoot. From the experimental results, OA system has a good response with a final pH value of 7±0.09 that can also be concluded this system is very suitable for long-term research. [ABSTRACT FROM AUTHOR]

In the industrial world, mixing operations are very widely used to process raw materials into products such as petroleum, chemicals, and various other types, so increasing the effectiveness of mixing operations is necessary. Usually, in industrial-scale plants, the conventional PID controller is used in the main controllers that are relied upon, but they often underperform, especially when dealing with non-linear systems. In this research, a neural network (NN)-based controller is proposed to overcome that problem. The plant model used for the simulation in this research is a mixing water plant, where the temperature and water level in the mixture tank will be controlled. This plant consists of 2 water flow inputs, namely cold water and hot water, which flows into the mixed tank where the temperature and water level of the mixture will be maintained and controlled according to the desired set points by regulating the flow of cold water and hot water. There are two types of NN-based controllers in this simulation study. The first is NN-based controller which has inputs in the form of the set point (SP), the current step (n) process variable (PV), and the previous step (n-1) process variable, while the second is a NN-based controller with set point (SP), error, and change of error for the inputs. Both of these NN-based controllers were developed using feed-forward neural networks, and the simulation was conducted by using MATLAB/SIMULINK. The simulation results show that the proposed NN-based controllers provide better performances when compared to conventional PID controllers. The best performance is obtained using the NN-based controller that has inputs in the form of set point, error, and change of error, with settling time of 472.7 s and rise time of 242.0 s in controlling the temperature, and settling time of 984.4 s, rise time about 447.6 s in controlling the level, that is faster than the PID controller which has 613.7 s and 393.9 s for settling time and rise time respectively in controlling the temperature, while gives settling time of 3216 s and rise time 412.8 s in controlling the level. Moreover, the NN-based controller produces a system response that has no overshoot at all. [ABSTRACT FROM AUTHOR]

The paper extends recently developed idea of stable evaluation of the Gaussian kernel. Owing to this, the Gaussian radial basis function that is sensitive to the shape parameter can be stably evaluated and applied to interpolation problems as well as to solve differential equations, giving highly accurate results. But it can be done only with grids being the Cartesian product of sets of points, what limits the use of this idea to rectangular domains. In the present paper, by the association of an appropriate transformation with the mentioned method, the latter is applied to solve differential equations on quadrilateral irregular domains. As an example a biharmonic problem is taken into consideration. The numerical tests show high accuracy and usefulness of the method.. [ABSTRACT FROM AUTHOR]

The article considers the traveling salesman problem on plane with a finite set of detour points M1, M2,..., Mn. A heuristic method is proposed for finding an approximate solution to this problem, in which at the first step the convex hull of the set of points M1, M2,..., Mn is constructed. This method can be used to solve the simple pursuit problem with one pursuer and several evaders, when the players make a simple move. The goal of the pursuer is to minimize the time of catching the last evader, and the evaders try to maximize this time. Players are supposed to use piecewise-constant strategies, i.e. players can change their direction of movement (the pursuer can also change the order of pursuit), only at certain moments of the correction t0, t1,...,tn,.... It is also assumed that at each moment of correction t, the pursuer chooses the pursuit order based on minimizing path the length of detour path E1(t), E2(t),..., En(t). If we assume, in addition, that the pursuit should occur along a closed loop, then at each moment of the correction t the pursuer solves the traveling salesman problem with detour points E1(t), E2(t),..., En(t), P(t). [ABSTRACT FROM AUTHOR]

In this note, we discuss properties of the trace of the energy-momentum tensor and their implications for inflation models. One property is the decoupling of heavy degrees of freedom from low-energy dynamics. This is intuitively apparent from the effective field theory point of view, but one has to take into account the so-called trace anomaly to explicitly demonstrate the decoupling. It is relevant to scalaron decay in R2 inflation models. Another is a quantum contribution to a non-minimal coupling of a scalar field to gravity. It might modify inflation dynamics. The non-minimal coupling disappears from the action in the flat spacetime, but leaves the so-called improvement term in the trace of energy momentum tensor. We discuss the "natural" value of a non-minimal coupling from the renormalization group point of view. [ABSTRACT FROM AUTHOR]

Solar fields of parabolic troughs are extensive complex thermal hydraulic facilities. Intra-hour and intra-minute variabilities of the DNI, mainly caused by passing clouds, pose an operational challenge for parabolic trough power plants. Under perfect circumstances a solar field controller would adjusts the mass flow in such a way, that the design temperature is always maintained constant with a maximized focus rate. However, heterogeneous irradiance conditions or flow distribution may cause some solar field sections to temporarily overheat while others may not reach the set point temperature, which in turn leads to an economic loss. State of the art solar field controllers have only access to incomplete information on spatial DNI variability, from DNI measurements of few pyrheliometers. Solar field controllers could be optimized with access to highly resolved DNI informations both in space and time. Such DNI information can be provided by all sky imager (ASI) based irradiance monitoring systems. In a previous study we developed and benchmarked new solar field controllers with access to spatial DNI information from an ASI system for a 50 MWe plant close to Córdoba (Spain). Significant improvements in revenue were observed. Yet, this previous study was limited to 22 days only. In this study, we estimate the potential benefit of these new solar field controllers over a 2 year period on the basis of the simulation results over 22 days. The upscaling method makes use of DNI variability classes. Using the ASI data we obtain a significant improvement in revenue up to 2% for the 2 year period. [ABSTRACT FROM AUTHOR]

Precipitation is a main input to many hydrological applications, such as water management, flood forecasting and hydrological modelling. The goodness of the rainfall field estimation can thus affect their performances. Despite radar-based and satellite-based measurements have nowadays become very common and accurate, rain gauges monitoring stations are still needed. The gauge density and its spatial distribution are two of the key factors influencing the accuracy in precipitation estimation. Even if in the last decades many studies proposed several methodologies for the design of optimal monitoring networks, only few studies use hydrological model performance as a design criterion. The purpose of this study is to define the optimal rain gauge network for the Mignone River catchment (Italy). The optimal network is defined through a multi-objective optimization approach, where the interpolation error of precipitation is minimised and the performance of a hydrological model based on the Width Function Instantaneous Unit Hydrograph theory is maximised. The optimization is run both without and with constraints, which are based on rainfall patterns. A score to choose the best set of points in the Pareto front is presented. The results suggest that there are preferential areas where sensors locations achieve optimal interpolation error and model performance. [ABSTRACT FROM AUTHOR]

The paper deals with investigation of the important problem of processing the ophthalmic data on the post-operation status of patients. The groups of patients differ by the type (technology) of fixing the intraocular lenses (IOL). Validity of each type of technology is estimated by computation of criteria for distinction of data between groups. The initial information comprises measurements of several ophthalmic indices. The samples on each index are very short; in each index, as a rule, the samples of patients’ groups overlap each other; any probabilistic characteristics of the measuring indices are unknown; any probabilistic characteristics of the measuring errors are also unknown. So, the standard methods of mathematical statistics can be applied only in the formal way and have shown to be inefficient. In contrast, the Hausdorff distance (from the set theory) as the criterion of distinction between two samples (both for one- and, especially, for two-dimensional indices) demonstrated to be reliable to distinct the patient’s status. Computations of the Hausdorff distance are valid for any relative location of point sets under comparison. [ABSTRACT FROM AUTHOR]

PI and PID controllers are usually found to provide poor performance for high-order, nonlinear processes, and multiple-input and multiple-output (MIMO) systems with strong loop interactions. One of the most common multivariable system found is the distillation column. In this study, a new structure of fuzzy self-tuning PI (fuzzy-PI) controller for distillation column is proposed. The values of Kp and Ki are initially tuned with Ziegler-Nichols closed loop method and are always updated based on the system's condition. With the self-tuning structure, the fuzzy-PI controller improves the conventional PI controller in terms of the linear distillation column control performance. The controllers' performance are tested by XD and XB set point change and XF disturbance change. [ABSTRACT FROM AUTHOR]

A proportional – integral controller retuning is performed on formaldehyde production process at PT X. Retuning is carried out to improve the controller performance on the process. The process model is estimated by a first order plus dead time model (FOPDT), and then the controller parameters are tuned using the Ziegler-Nichols (PRC), Wahid-Rudi-Victor (WRV), Cohen-Coon, autotuning, and fine tuning. The controller performance is tested using set point (SP) tracking and disturbance rejection with integral of square error (ISE) as performance indicator. There are three controllers that are tested, i.e., the steam flow controller (FIC -102), air temperature controller (TIC – 101), and tank level controller (LIC – 102). Fine tuning method provides a better control performance for FIC - 102 and TIC - 101, while autotuning method provides a better control performance for LIC - 102 compared to the previous settings in the field. Performance improvement for set point (SP) tracking are 81,59% (FIC – 102), 94,11% (TIC – 101), and 85,61% (LIC – 102). While performance improvement for the disturbance rejection are 95,5% (FIC – 102), 94,53% (TIC – 101), 93,16% (LIC – 102). Thus, retuning PI controllers work well and by using the suggested controller tuning, a better controller performance of PT X can be achieved. [ABSTRACT FROM AUTHOR]

The most human The most human form of energy today is electricity. While one of the fuels capable of producing electricity is biogas. Biogas produced by cattle farmers has great potential in Indonesia. However, from the electricity sector the generator set output still cannot produce good stability if there is a change in load. The speed of rotation of the generator is strongly influenced by frequency and voltage. While the rotating speed of the generator is caused by changes in the load that changes continuously. In testing the close loop system is in accordance with the desired set point value of 3000 RPM and the response reaches a steady state. Even though a continuous load variation is carried out the system will still maintain the set point. While the open loop response test shows that the system is not can reach set point. This is because the system is not controlled by the control. The PV value is not equal to the SV value. This proves that if the system is given a different voltage continuously, the RPM or rotation speed also varies. From the simulation results, the maximum overshoot value is 8.6%, 0.1 second delay time, 0.4 second rise time, 0.8 second peak time and 4 second settling time. With the PID parameter obtained at the generator speed rotation system, that is for Kp=1.4, Ki 1.3 and Kd=0.12. As for modeling validation, get an error of 0.25%. [ABSTRACT FROM AUTHOR]

Due to a huge amount of energy consumed by an air conditioning (A/C) system in buildings, several methods and technologies have been developed to enable this system works in the more efficient way. One of the methods is to regulate the room temperature without ignoring human thermal comfort in the air conditioned space. In the A/C system, the higher the room temperature setting, the lower the energy consumption. To investigate the effect on the energy consumption of A/C system due to difference room temperature setting, an experimental study on the A/C system with cooling capacity of 3.7 kW using R32 as working fluid was conducted. In this study, the room temperature was set from 20 to 24°C, with temperature increment of 1°C. The measurements were carried out for 180 minutes for each room temperature setting. The results show that the energy savings due to increment of 1°C from 20 to 21°C, 21 to 22°C, 22 to 23°C and 23 to 24°C are varied. The biggest and lowest energy consumption reductions occur at 21 to 22°C and 23 to 24°C, which are 13.5% and 10.7%, respectively. As a result, the increment in room temperature setting of 1°C from 21 to 22°C generates the most significant energy saving as compared to other setting temperatures. [ABSTRACT FROM AUTHOR]

This paper is concerned with relationships among G-inverse shadowing property, G-expansivity and G-Sensitivity. In the class T_0, G-inverse shadowing does not imply G-expansive. We generalize the concept of eventually sensitive to G-space, and we see that G-inverse shadowing does not imply eventually G-sensitive in the class T_0. On the other hand, G-inverse shadowing with totally G-transitive imply G-sensitive in the class of continuous methods T_c. So, G-sensitive is obtained from G-inverse shadowing and dense set of G-periodic point . [ABSTRACT FROM AUTHOR]

In recent years, a 3D laser scanner has increasing attention as one of the modern technologies to digitizing the 3D object surface in manner to obtain a mathematical representation of object’s and surface reconstruction. Due to limitations of a 3D laser scanners, the row point cloud, which are acquired from these techniques, included some undesired information such as noise points and associated huge number of points in point cloud. In the present paper, a new proposed point cloud simplification algorithm for scanned object using 3D laser scanner (Matter and Form) has been adopted in manner to extract the necessary geometric features which represented by a 3D surface curvature. This algorithm based on instantaneous calculation of 3D Gaussian curvature for each data point. The curvature value indicates both quality of the topical calculations and a noise isolating and detection in the point cloud set. A MATLAB environment has been adopted to construct a proposed point cloud simplification algorithm program, this program has been proved using a practically case studies. The results proved the effectiveness of the proposed algorithm in local calculation of 3D curvature and detection and isolate the noise points in point cloud where the percent of data which was ignored as noisy data point were (49.29%) and (57.30%), of total data point number after applying the algorithm for the first and second proposed case studies respectively. [ABSTRACT FROM AUTHOR]

Mobile mapping systems (MMS) are becoming used in standard geodetic tasks more common in the last years. This paper deals with independent accuracy evaluation of MMS RIEGL VMX-450, and recommendation for which types of tasks is effective to use tested MMS. Data from mobile laser scanning and mobile photogrammetry obtained by tested system were evaluated. The new test point field was built in area of Advanced Materials, Structures and Technologies (AdMaS) research centre that is part of Brno University of Technology. The points were signalized and stabilized using reflective checkerboard targets that were placed on roads, traffic signs, and buildings. Geodetic network and test point field were measured with high accuracy by Trimble R8s GNSS system and Trimble S8 HP total station. The coordinates were calculated by geodetic network least squares adjustment with a combination of GNSS and terrestrial measurements. This field can be also used for other high precise testing/calibration purposes. The accuracy evaluation was done based on three sets of coordinates obtained by: 1) geodetic network least squares adjustment, 2) georeferenced laser scanning point cloud, 3) mobile photogrammetry. Two typical point groups were tested. The first group contains points located at the ground (horizontal targets), this is used for the standard task - mapping of extra-urban roads. The second group contains points at different height levels (vertical targets), this is standardly used for mapping in urban areas. The results of this analysis can be beneficial for people in geodetic praxis. [ABSTRACT FROM AUTHOR]

The control problem of a wind system considered as an isolate source of power has been taken into account. The wind system is composed of a horizontal-axis wind-turbine connected to synchronous generator. In order to simulate the dynamic behavior of wind system, appropriate mathematical models for both the horizontal-axis wind-turbine and the synchronous generator have been considered. The proposed control algorithm relies on the fuzzy logic framework exploiting the knowledge of few steady state working conditions (control input - controlled output value pairs). The fuzzy logic scheme, not only properly combines the knowledge within the working point data set, but it also is able to consider the controlled variable deviation (control tracking error) and its first time derivative. Then few results of control problems are finally illustrate in order to prove the reliability of the suggested enhanced control technique. [ABSTRACT FROM AUTHOR]

An approach to identify critical loops within connected systems especially in co-simulation frameworks is presented. Therefore a classification of the coupling signals is done to distinguish between different types of signals: continuous, discontinuous, discrete and flat. Based on this classification structural loops between the connected subsystems are identified and rated to get critical loops in sense of coupling effort. This information supports application engineers to identify critical signals from a coupling point of view and to set proper coupling methods to handle these coupling signals efficiently [ABSTRACT FROM AUTHOR]

Effective linearity measures are useful in image processing. Sets of points with relatively high linear pattern are taken as support region. In this work, we introduce a linearity measure known as convex hull area-length ratio to obtain support region for boundary points of an image. The measure is invariant under transformations such as scaling, rotation and translation. The algorithm is using simple computation and resistant to protrusion in data set. Dominant point detection is the extension application after the support region determination. The capability of the measure is presented graphically with boundary points of images. [ABSTRACT FROM AUTHOR]