Systematic Design Procedure Research Articles

Large-aperture 256-element fully populated random array for therapeutic ultrasound applications: Experimental study of its functionality and characterization of the radiated field

Recently, a new method has been proposed for designing random high-intensity focused ultrasound (HIFU) arrays with the maximum possible filling factor and polygonal elements of equal area, based on capacity constrained tessellation [Rosnitskiy et al., IEEE Trans. UFFC (2018)]. Following this approach, a 256-element piezocomposite array with a radius of curvature of 150 mm, a diameter of 200 mm, and an operating frequency of 1.2 MHz was designed at the Laboratory for Industrial and Medical Ultrasound (LIMU) of Moscow State University. The array was subsequently manufactured by Imasonic (France). It can be driven using a Verasonics ultrasound engine. Electrical matching was performed for each element using matching network created by Image Guided Therapy (France). This report presents the system design procedure and experimental results for array characterization using acoustic holography and acoustic power measurements using the radiation force balance. In addition, a theoretical study was carried out using the “HIFU beam” simulator developed at LIMU (freely available at www.limu.msu.ru) to assess the array's ability to achieve highly nonlinear regimes with shocked pressure waveforms. The possibility of using the array for HIFU applications such as acoustic levitation and manipulation, histotripsy and transcostal HIFU therapy is discussed. [Work supported by RSF 19-12-00148.]

Robust pole placement and random disturbance rejection for linear polytopic systems with application to grid-connected converters

This paper deals with an application of robust state feedback pole placement for discrete-time polytopic systems with stochastic disturbance attenuation. A set of stochastic signals is described using differential entropy functional. In the paper the parameter-independent robust state-feedback controller design procedure for linear discrete-time polytopic systems with theoretic-information constraints on the set of external random disturbances is proposed. Such additional constraints allow to find a tradeoff between H2 and H∞ control with better control energy consumption and improved robustness against random disturbances. This approach is applied to PWM inverters with LCL filters connected to the grid under uncertain parameters. Simulation results indicates that proposed controller allows to improve frequency and transient responses with better performance than existing ones.

First mode damping ratio oriented optimal design procedure for damped outrigger systems with additional linear viscous dampers

The damped outrigger system is in widespread use as a damping modification system for tall buildings that provides high additional damping in addition to the bending back effect against the core. However, while the enhanced seismic performance of damped outrigger systems was confirmed in previous studies all over the world, a general-purpose optimal design method focusing on modal damping ratios has not been established yet. This paper proposes an optimal damper design kit composed of a first mode damping ratio oriented design policy, simple equations of optimal damper-connection stiffness ratio to maximize first mode damping ratio, a machine learning model to estimate first mode natural period and damping ratio. The tenability of the first mode damping ratio-oriented design policy was confirmed by performing complex modal analyses on single to quad damped outrigger systems incorporating linear viscous dampers and assigning realistic stiffness values to the outrigger trusses. The simple design equations of optimal damper-connection stiffness ratio and the machine learning model for first mode characteristics were developed based on a large number of analytical results. The proposed optimal design kit has been made available as a web application-based design tool.

Tracking control with disturbance rejection of nonlinear fractional order fuzzy systems: Modified repetitive control approach

This paper addresses the problem of tracking control and disturbance rejection for nonlinear fractional order systems. To this end, based on Takagi-Sugeno (T-S) fuzzy modeling approach and a fractional order modified repetitive controller, an output feedback strategy is constructed for a class of nonlinear fractional order systems. T-S fuzzy model represents an accurate model of nonlinear fractional order systems and simplifies the procedure of control system design. By introducing a novel Fuzzy Lyapunov Function (FLF), sufficient conditions are established in the framework of Linear Matrix Inequalities (LMIs) to ensure the stability of the closed-loop system. Based on the achieved conditions, it is shown that the external disturbance is attenuated and the output of the system tracks the periodic reference input with an ignorable error. Lastly, three examples including fractional order Chua’s circuit, Lorenz-like and Chen systems are performed to show the efficiency of the method proposed in this paper.

Design, Fabrication, and Experimental Results of a Pulsed Power-Based Four-Stage Induction Coilgun for Launching a Heavy Projectile

Since 2016, Hanwha Defense Corporation has been working on applying electromagnetic launch technologies such as induction coilguns to cold-launch systems that can launch guided missiles. First, a design procedure of a multistage coilgun system based on the pulsed power driven by capacitor banks was developed using the Taguchi method, and a laboratory-scale three-stage coilgun capable of launching a 21.68-kg projectile at a maximum speed of 27.5 m/s was built and the results of the experiment were announced in 2018. In this article, we design, fabricate, and present the experimental results of a pulsed power-based four-stage induction coilgun using the proposed procedure to prove the validity of the electromagnetic launch technology for heavy missile launch. In this experiment, a 100-kg projectile was fired under 4-kV charging conditions, the maximum speed of the projectile was 25 m/s or more, and an efficiency of 15% was achieved without considering the mass of the armature. In this study, by accelerating a 100-kg projectile to 27 m/s, the feasibility of an electromagnetic launcher developed for heavy missile launch was verified.

Achieving a realistic design for a superconducting gantry with large momentum acceptance for proton therapy

Purpose:A systematic design procedure for a superconducting gantry is presented. To increase the momentum acceptance of the gantry beamline, alternating-gradient combined-function magnets were used to suppress dispersion. Methods:The main difficulties and challenges occurring in the design procedure, such as the difference between low- and high-order optics and the difference in beam behavior between simplified optics models and realistic magnetic fields, were analyzed. On the basic of these analyses, a step-by-step iterative design approach was proposed. In these steps, a genetic algorithm (GA) was used for multi-objective optimization, and graphics processing unit (GPU) acceleration was adopted for realistic model simulation. Results:The results of the design demonstrated that momentum acceptance of −7%∼5% was achieved for particle tracking in realistic magnetic fields. Conclusions:Using a GA, multi-objective optics fitting up to the fifth order became feasible. The optimization procedure was also more intelligent compared with the traditional one, which depends on experience and manual intervention. The use of GPU acceleration in magnetic field calculation and particle tracking dramatically reduced the overall optimization time. Finally, design optimization for a large momentum acceptance gantry beamline with realistic magnetic fields was achieved.

Implementation of Decision Support Personnel Recruitment System for Laguna State Polytechnic University-San Pablo City Campus

The Laguna State Polytechnic University-San Pablo City Campus viewed the hiring of possible employees as a major problem in the university because it takes time for the human resource department to facilitate the process of recruitment. The main objective of the study is to implement a web-based decision support personnel recruitment system that can screen qualified applicants, assist the human resource personnel in ranking the applicants and generate reports. The system was developed using PHP, CSS, Java Script and XHTML as programming platform and MySQL as database engine. The system design, testing and evaluation procedures were presented. Test results show that the project is secured and can be best viewed in Google Chrome, IE7+, Mozilla Firefox and Opera Mini using personal computer, laptop, tablet and mobile phone. Two questionnaires were distributed - ISO 9126 Software Quality Matrix and acceptability survey to determine whether the implementation was successful. Based from the results of evaluation conducted, the project was rated as excellent with an overall mean of 4.52. The users also agreed that the system was acceptable in terms of interface, operability, security and portability. It was recommended that the system should allow multiple applications for different job vacancies and the ranking of applicants with the same points should be tie regardless of who submitted the application first.

A method for assessing of ship fuel system failures resulting from fuel changeover imposed by environmental requirements

Environmental regulations instigated the technological and procedural revolution in shipping. One of the challenges has been sulfur emission control areas (SECA) and requirement of fuel changeover. Initially, many reports anticipated that new grades of low sulfur fuels might increase various technical problems in ship operation. This research develops a simple and easy to use method of the failure severity and intensity assessment in relation to fuel changeover. The scale of failure rate in the ship’s fuel system was evaluated qualitatively and quantitively, using developed failure frequency indicator and the time between failure. Based on 77 records of fuel system failures collected on seven ships, it has been found that frequency of failures related to SECA fuel changeover is on average nearly three times higher compared to the rest of sailing time. Their severity did not significantly change, but the structure of failures changed considerably. The method and presented results may help in improvement of ship’s systems design and on-board operational procedures.

Comparison of Wind Tunnel Test Data for Low-Rise Buildings with Main Wind Force Resisting System Design Procedures

The adequacy of the directional and envelope procedures for the design of the main wind force resisting system is not well understood. The purpose of this study is to evaluate the directional and envelope procedures based on wind tunnel test data for a set of low-rise enclosed buildings with gable-shaped roofs in open terrain (Exposure C). The base shear force and the conditional reliability index are used to determine the adequacy of the procedures. The base shear was compared to the design base shear in each direction based on the horizontal component of the wind load on the wall and roof. The reliability index, β conditional on the occurrence of the design wind speed was computed for a range of system capacities. The main findings are (1) the directional procedure produced a larger design base shear compared to the envelope procedure, primarily due to the difference in external pressure coefficients, (2) the directional procedure provided a higher β, and (3) the envelope procedure provided a β that did not meet the standard target β equal to 3.0 for the main wind force resisting systems with low variability in capacity, but neither procedure met the standard target β for the main wind force resisting systems with high variability in capacity.

Reprint of: Bio-based design methodologies for products, processes, machine tools and production systems

The paper explores and presents results of an investigation handling design methodologies using the bio-space and biological phenomena combined with the technical space for the development, design and application of products, machine tools, processes and manufacturing systems carried out by a multinational team including Fraunhofer and CIRP fellows. The main biological approach for designing was bio-inspiration. However, links and examples implementing bio-integration and bio-intelligence were also considered and analyzed during the investigation.The paper describes a systematic design procedure starting from requirements and applications related to manufacturing, using well-known theories and experience in engineering, however analyzing and applying biological materials, properties, structures, phenomena and complete systems. Sustainability aspects combined with the immense and ever growing capacity of ICT and digitization possibilities provided new options for design methodologies.A moveable and flexible machine tool was virtually used as a demonstrator to describe the new methodology. It was proved that the ongoing process of learning from nature and applying biological phenomena, structures and materials, together with new technologies such as Additive Manufacturing (AM) can develop new ideas, processes, manufacturing systems, and products with benefits to performance, productivity, efficiency and sustainability. Nature and biological domains can be integrated, can inspire, be implemented or even applied as an intelligent system in the design procedure.

Robust Skin Attachable Sensor for Core Body Temperature Monitoring

We designed a skin-attachable sensor for measuring core body temperature (CBT). Past studies on non-invasive CBT measurement did not consider heat loss and measurement errors caused by ambient convection. To address the effect of convection, we designed a heat flow path in the structure of the CBT sensor. Topology optimization provided a systematic design procedure without the need for numerous, complex trials. By using topology optimization, we developed an optimized aluminum structure, a truncated cone with a hole. The sensor with the aluminum structure was evaluated by numerical calculation and experiment. We determined that the heat loss induced by ambient convection was effectively reduced, and the CBT estimation accuracy and robustness to convection were improved. The feasibility of the CBT sensor was demonstrated in an experiment using a phantom with an accuracy of 0.1 °C, showing potential for applications to thermal and fluidic devices.

Robust repetitive control for a class of uncertain nonlinear systems

AbstractThis paper presents an output‐feedback repetitive control method for a class of systems with nonlinearities, unknown state‐dependent uncertainties, and external disturbances. An additive‐state‐decomposition approach is used to decompose the system under study into a primary linear periodic system in charge of repetitive‐control tracking task and a secondary linearized system in charge of robustly stabilization task. Such a treatment not only significantly simplifies system analysis and controller design, but also provides an effective method to cope with the intrinsic constraints between tracking and disturbance rejection. Another attractive point lies in two aspects. On one hand, a periodic term from the nonlinearity in the plant is extracted to be treated in the primary system and the known plant information is used to design controller parameters, which greatly improves the disturbance rejection ability of the system. On the other hand, repetitive control gain, feedback control gain, and the observer gain are optimized through an optimization algorithm by introducing an index to evaluate the overall system performance. System stability criteria and design procedure are developed. Finally, a case study on the tracking control of a chuck‐piece system demonstrates the validity of the proposed method. Comparisons with some existing methods show that the proposed method achieves better performances in both signal tracking and disturbance rejection.

Inline Combline Filters of Order N With up to N + 1 Transmission Zeros

In this article, we describe several alternative inline implementations for combline filters with transmission zeros (TZs) located both below and above the passband. A systematic design procedure is also presented using a lumped-element equivalent circuit. Following the design procedure that we propose, up to $N+1$ TZs can be implemented with an inline filter of order $N$ . The generation of the TZs is explained physically in terms of mixed inductive and capacitive couplings. Several filters are also manufactured and tested. Good agreement between the measured and simulated results is demonstrated, thereby fully validating the new filter concepts.

Hydraulic Design of the Center-Pivot Irrigation System for Gradually Decreasing Sprinkler Spacing

Design strategies that enhance modern irrigation practices, reduce energy consumption, and improve water use efficiency and crop yields are fundamental for sustainability. Although microirrigation is currently a widely applied method, center-pivot irrigation systems have become very popular on large farms, thanks to their automation, wide-coverage, and reliability. Different design procedures have been proposed, even though some aspects have not been solved yet. This paper presents a simple design procedure for center-pivot systems using a gradually decreasing sprinkler spacing along with a pivot lateral, which makes it possible to set favorable and uniformly distributed water application rates. The sprinkler spacing distribution along the radial direction is derived by considering just one dimensionless group accounting for the geometric and hydraulic input parameters. According to this outcome, the results showed that the suggested procedure made it possible to select the sprinkler characteristics and the pipe diameter based on the desired input parameters, i.e., the uniform water application rate and the lateral length. For assigned input parameters, the lateral length is delimited by a threshold value, indicating that lateral lengths longer than that threshold value require the modifications of a sprinkler flow rate or pipe diameter. Finally, applications based on the proposed hydraulic design procedure were performed and discussed for two different cases.

Three-dimensional terminal angle constraint finite-time dual-layer guidance law with autopilot dynamics

Considering the problem of intercepting a target at desired terminal angles in the three-dimensional (3D) space, this paper proposes a finite-time dual-layer guidance law with consideration of the second-order autopilot dynamics. The proposed guidance law owns a cascaded structure, which is divided into an outer system and an inner system. To achieve the finite-time convergence, the outer and inner controllers are developed based on the nonsingular terminal sliding mode control. With the aid of the command filter, which can compute the first and the second derivatives of the virtual signal simultaneously, the design procedure of the fourth-order guidance system is simplified into two steps. Moreover, extended state observers are used to estimate the unknown target maneuver and the acceleration derivative of the missile, which facilitates the real implementation. Simulation results verify the performance of the proposed guidance law.

Controller Design of an Active Front-End Converter Keeping in Consideration Grid Dynamic Interaction

This paper presents a systematic control design procedure for an active front-end (AFE) converter connected to a power electronics embedded grid. A parametric model of the grid is firstly identified using the AFE itself to excite the system. This model is then integrated with AFE one in order to obtain a global system representation. Subsequently, a globally optimized local controller is synthesised for the AFE keeping in consideration interaction between the converter and the grid. The proposed method is finally tested experimentally and its performance is compared with a traditional Proportional-Integral (PI) controller in a dq synchronous reference frame.

Recommendation Systems For E-commerce Systems An Overview

Due to the huge expand in global markets and financial transactions, the importance of E-commerce has grown significantly, so to achieve fully functioning, scalable, reliable, efficient, secure, and user-friendly E-commerce system, Adequate system analysis and design procedures are essential. On the other hand The internet vast growing has totally altered the way most companies work. The Internet has created a means for e-Commerce the internet has created a way to provide a unique avenue for companies and customers to sell and buy goods and services. When creating an e-commerce website, there are several goals that must be taken into account, one of them is how to Increase the site’s efficiency to ensure customer turnout and thus achieve the required material profits. There are several methods that are followed to increase the efficiency of the site. One of these methods is the recommender system. This paper produces a study overview of the value of recommended systems and thoroughly analyzed Collaborative Recommender System (CF) techniques with its techniques., which presents proposals to customers according to their interests, making it easier for the customer to search and thus choose the goods that suit him.

A Novel Procedure for Quick Design of Off-Grid PV Water Pumping Systems for Irrigation

It is known that meteorological variables from meteorological online services can be used for the design of photovoltaic (PV) water pumping systems for irrigation. The software LORENTZ COMPASS in such a manner uses as inputs solar irradiation, precipitation, and ambient temperature collected by the NASA Langley Research Centre over a period of more than 20 years. This paper proposes a novel procedure that uses the sunshine duration, precipitation, and ambient temperature as inputs. These inputs were collected by Weather Online UK during a period of 25 years. The effects of different data collection periods and data availabilities on the design of the PV water pumping system are also analysed and discussed. Along with the meteorological data, the proposed procedure uses as inputs datasheets from manufacturers of pumping systems and PV modules. The procedure is based on the Sivkov model that correlates the global horizontal irradiation with the sunshine duration and the elevation angle of the Sun. A case study, i.e., an existing PV water pumping system designed using LORENTZ COMPASS is used as reference for purposes of comparison and validation of the procedure. The results of the comparison showed a high level of accuracy, and a number of interesting conclusions are drawn from them.

Compactmulti‐frequencysystem design forSWIPTapplications

The potential advantages of simultaneous wireless information and power transfer (SWIPT) applications have necessitated innovations in the associated circuits and systems. This article, therefore, explores the concept of cascaded resonators, for the first time, in the design of a compact-size defected ground structure (DGS)-based tri-band wireless power transfer (WPT) system to advance the SWIPT technology. The design is augmented with a systematic design procedure that is preceded by the development of a new double-elliptic DGS-based tri-band resonator. Initially, the analysis of the proposed resonator is performed to identify the impact of defect size on the bandwidth. Subsequently, the resonators are cascaded to achieve a tri-band functionality and then utilized in the design of WPT. The designed WPT operates at 0.3, 0.5, and 0.9 GHz, and takes a compact size of 39 × 13 mm2. The measurement of the realized WPT with the transmitter and receiver, separated by the distance of 10 mm, provides an efficiency of around 60% at all three bands with the figure of merit values of about 0.5. Furthermore, the proposed design achieves a bandwidth of more than 3 MHz bandwidth at the frequencies corresponding to communication standards.

Systems Medicine Design for Triple-Negative Breast Cancer and Non-Triple-Negative Breast Cancer Based on Systems Identification and Carcinogenic Mechanisms.

Triple-negative breast cancer (TNBC) is a heterogeneous subtype of breast cancers with poor prognosis. The etiology of triple-negative breast cancer (TNBC) is involved in various biological signal cascades and multifactorial aberrations of genetic, epigenetic and microenvironment. New therapeutic for TNBC is urgently needed because surgery and chemotherapy are the only available modalities nowadays. A better understanding of the molecular mechanisms would be a great challenge because they are triggered by cascade signaling pathways, genetic and epigenetic regulations, and drug–target interactions. This would allow the design of multi-molecule drugs for the TNBC and non-TNBC. In this study, in terms of systems biology approaches, we proposed a systematic procedure for systems medicine design toward TNBC and non-TNBC. For systems biology approaches, we constructed a candidate genome-wide genetic and epigenetic network (GWGEN) by big databases mining and identified real GWGENs of TNBC and non-TNBC assisting with corresponding microarray data by system identification and model order selection methods. After that, we applied the principal network projection (PNP) approach to obtain the core signaling pathways denoted by KEGG pathway of TNBC and non-TNBC. Comparing core signaling pathways of TNBC and non-TNBC, essential carcinogenic biomarkers resulting in multiple cellular dysfunctions including cell proliferation, autophagy, immune response, apoptosis, metastasis, angiogenesis, epithelial-mesenchymal transition (EMT), and cell differentiation could be found. In order to propose potential candidate drugs for the selected biomarkers, we designed filters considering toxicity and regulation ability. With the proposed systematic procedure, we not only shed a light on the differences between carcinogenetic molecular mechanisms of TNBC and non-TNBC but also efficiently proposed candidate multi-molecule drugs including resveratrol, sirolimus, and prednisolone for TNBC and resveratrol, sirolimus, carbamazepine, and verapamil for non-TNBC.