Amending and Changing the Seismic Behavior of K-bracing by Yielding Damped Braced Frame (YDBF)

An inactive control method is to prepare the kinds of dampers as inactive energy wasting factor for metallic structure buildings. Yielding metallic dampers (or excurrent) are metallic devices which can waste energy in an earthquake by the effect of non-elastic changes of metals, also in the braced systems of structure buildings, they can improve resistance against earthquake and their damages control potential significantly. With regard to the geometry of K-bracing and the weaknesses which are by the effect of a resultant of two compressive and tensile forces of Bersnon, Iran's earthquake regulation in 2008 has exerted some limitations for using of this system. Therefore, in this research we tried to eliminate these limitations to some extent by using of metallic dampers. For doing this research, by using of two software of finite components (sap2000, Abaqus) with static non-linear analysis, we achieved the same purpose. This kind of dampers due to the simplicity of their installation and low cost of them can be applied both in new and existing buildings.

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A New Control Method for Vibration and Noise Suppression in Switched Reluctance Machines

Energies ◽

10.3390/en12081554 ◽

2019 ◽

Vol 12 (8) ◽

pp. 1554 ◽

Cited By ~ 3

Author(s):

Man Zhang ◽

Imen Bahri ◽

Xavier Mininger ◽

Cristina Vlad ◽

Hongqin Xie ◽

...

Keyword(s):

Control Strategy ◽

Noise Suppression ◽

Control Method ◽

Negative Impact ◽

Low Cost ◽

Radial Force ◽

Torque Control ◽

Transient Condition ◽

Switched Reluctance ◽

Switched Reluctance Machines

Due to their inherent advantages such as low cost, robustness and wide speed range, switched reluctance machines (SRMs) have attracted great attention in electrical vehicles. However, the vibration and noise problems of SRMs limit their application in the automotive industry because of the negative impact on driver and passengers’ comfort. In this paper, a new control method is proposed to improve the vibratory and acoustic behavior of SRMs. Two additional control blocks —direct force control (DFC) and reference current adapter (RCA)—are introduced to the conventional control method (average torque control (ATC)) of SRM. DFC is adopted to control the radial force in the teeth of the stator, since the dynamic of the radial force has a large impact on the vibratory performance. RCA is proposed to handle the trade-off between the DFC and ATC. It produces an auto-tuning current reference to update the reference current automatically depending on the control requirement. The effectiveness of the proposed control strategy is verified by experimental results under both steady and transient condition. The results show that the proposed method improves the acoustic performance of the SRM and maintains the dynamic response of it, which proves the potential of the proposed control strategy.

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Design and multichannel electromyography system-based neural network control of a low-cost myoelectric prosthesis hand

Mechanical Sciences ◽

10.5194/ms-12-69-2021 ◽

2021 ◽

Vol 12 (1) ◽

pp. 69-83

Author(s):

Saygin Siddiq Ahmed ◽

Ahmed R. J. Almusawi ◽

Bülent Yilmaz ◽

Nuran Dogru

Keyword(s):

Neural Network ◽

Control Method ◽

Low Cost ◽

Hand Movement ◽

Cost Effective ◽

Network Control ◽

Human Hand ◽

Prosthetic Hand ◽

Myoelectric Prosthesis ◽

System File

Abstract. This study introduces a new control method for electromyography (EMG) in a prosthetic hand application with a practical design of the whole system. The hand is controlled by a motor (which regulates a significant part of the hand movement) and a microcontroller board, which is responsible for receiving and analyzing signals acquired by a Myoware muscle device. The Myoware device accepts muscle signals and sends them to the controller. The controller interprets the received signals based on the designed artificial neural network. In this design, the muscle signals are read and saved in a MATLAB system file. After neural network program processing by MATLAB, they are then applied online to the prosthetic hand. The obtained signal, i.e., electromyogram, is programmed to control the motion of the prosthetic hand with similar behavior to a real human hand. The designed system is tested on seven individuals at Gaziantep University. Due to the sufficient signal of the Mayo armband compared to Myoware sensors, Mayo armband muscle is applied in the proposed system. The discussed results have been shown to be satisfactory in the final proposed system. This system was a feasible, useful, and cost-effective solution for the handless or amputated individuals. They have used the system in their day-to-day activities that allowed them to move freely, easily, and comfortably.

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Adsorption of UV254 in Kerian River water onto ZeliacTM: Analysis using linear and non-linear forms of isotherm models

Global NEST Journal ◽

10.30955/gnj.001968 ◽

2017 ◽

Vol 19 (1) ◽

pp. 74-81 ◽

Cited By ~ 1

Keyword(s):

River Water ◽

Function Analysis ◽

Low Cost ◽

Error Function ◽

Linear Regression Analysis ◽

Freundlich Isotherm ◽

Linear Analysis ◽

Isotherm Models ◽

Freundlich Isotherms ◽

Non Linear

The composite media, ZeliacTM was developed with the initial aim to provide low cost adsorbent with promising adsorption capacity. This study was conducted to investigate the removal of UV absorbance at 254 nm (UV254) in Kerian river water using ZeliacTM as the media. Batch experiments study was carried out to determine the optimum removal of UV254 by ZeliacTM. The experimental data were fitted to Langmuir and Freundlich isotherms to investigate the adsorption mechanism. The results from batch study exhibit that ZeliacTM is capable to remove 74.4% UV254 at the dosage of 7g/100 ml. Linear isotherm analysis suggests that the best fitting linear line is Freundlich isotherm with R2 values of 0.9294 indicating multilayer adsorption. Similarly, non-linear regression analysis reveals that the adsorption of UV254 by ZeliacTM is attributed by physisorption. The non-linear Freundlich isotherm gives a better fit to the adsorption of UV254 than Langmuir isotherm with R2 values of 0.9488. The results are supported with low values of X2, ARE, HYBRID and MPSED from the error function analysis.  Additionally, it is noted that the linear analysis overestimates the constant parameters’ values for Freundlich isotherm, which cause larger errors as estimated by the error function analysis. Hence, non-linear analysis is more appropriate in explaining the batch experiment data.

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Design of Orbit Controls for a Multiple CubeSat Mission Using Drift Rate Modulation

Aerospace ◽

10.3390/aerospace8110323 ◽

2021 ◽

Vol 8 (11) ◽

pp. 323

Author(s):

Youngbum Song ◽

Sang-Young Park ◽

Geuk-Nam Kim ◽

Dong-Gu Kim

Keyword(s):

Drift Rate ◽

Time Synchronization ◽

Control Method ◽

Low Cost ◽

Relative Distance ◽

Laser Communication ◽

Surveillance Systems ◽

Rate Modulation ◽

Orbit Control ◽

Orbital Drift

For the low-cost improvement of laser communication, which is critical for various applications such as surveillance systems, a study was conducted on relative distance control based on orbital drift rate modulations for multiple CubeSats during formation flying. The VISION mission covered in this paper comprises two CubeSats to demonstrate laser communication technology in space. During the mission, the deputy CubeSat changes the relative distance to execute mission objectives within various scenarios. Impulsive controls decrease, maintain, and increase the relative distance between the CubeSats by changing the orbital drift rates. The simulation results indicated that the desired orbital operation can be conducted within a given ΔV budget. In addition, the errors in the orbit determination, thrust maneuvers, and time synchronization were analyzed to satisfy the mission requirements. The mass-to-area ratio should be matched to adjust the relative distance between satellites with different properties by drift rate modulation. The proposed orbit control method appropriately operated the VISION mission by adjusting the drift rate modulation. The results of this study serve as a basis for the development of complex orbit control simulations and detailed designs that reflect the characteristics of the thrust module and operational aspects.

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Delivering More Fit-for-Purpose Wells with Low Cost Approach at Untapped Area Matured Field – Application of Cone Concept Statistical Approach

10.2523/iptc-21419-ms ◽

2021 ◽

Author(s):

M. Hatta M. Yusof ◽

M. Zarkashi Sulaiman ◽

Rahimah A. Halim ◽

Nurfaridah Ahmad Fauzi ◽

Ahgheelan Sella Thurai ◽

...

Keyword(s):

Statistical Analysis ◽

Statistical Approach ◽

Control Method ◽

Low Cost ◽

Volatile Oil ◽

Field Application ◽

Well Design ◽

Execution Phase ◽

Sand Control ◽

Fit For Purpose

Abstract This paper discusses the Case study of Field A in offshore Sarawak, Malaysia which focus on re-thinking development based on statistical analysis of the fields. Conventionally, well design is driven by subsurface requirement by targeting the high-reserve sand and well is designed to meet subsurface objectives. However, the conventional way may not be efficient to develop matured field environment due to the high CAPEX and the inconsistencies among well design especially in current volatile oil price period. The objective of this fit-for-purpose approach which is called "Cone Concept Statistical Approach" is to steer away from the conventional way of targeting only sweet spots whilst leaving the remaining potential resources undeveloped. Based on the statistical analysis and subsurface fields pattern, the "Cone Concept Statistical Approach" in which standardizing well design and trajectories was developed to extract the whole fields’ reserve at maximum. Well design boundaries were introduced to ensure this approach can be replicated throughout the field. Not only this study covers drilling perspective, completion perspective was also taken into consideration by exploring a cheaper and fit for purpose sand control method, considering it is a matured field with relatively short remaining field life. The Well Cost Catalogue for this field-specific approach was also developed which contains different types of design and completion, in order to holistically evaluate sand control method and identify the best option for the project moving forward. This "Cone Concept Statistical Approach" aims to enable operator to drill simple wells within the same allocated budget in which poses low-to-no risk in the design and execution phase. This promotes a learning curve to improve operation & HSE, and ultimately gets positive project economics. Since this simple approach can be implemented early on even during the pre-FEL stage, the FDP team & host authority can come together to jointly discuss the targets/platform ranking and segregate them into various phases. Hence, the number of platforms or drilling centers, and its location also can be optimized early on with this concept, and again, translating into further reduction in overall project cost. This paper will help other operators and host authority to understand better on how a specific development concept on statistical approach can result and turn the matured-challenging fields into more economically attractive projects – low overall development cost and maximizing the recovery.

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Aerial physical interaction via IDA-PBC

The International Journal of Robotics Research ◽

10.1177/0278364919835605 ◽

2019 ◽

Vol 38 (4) ◽

pp. 403-421 ◽

Cited By ~ 4

Author(s):

Burak Yüksel ◽

Cristian Secchi ◽

Heinrich H. Bülthoff ◽

Antonio Franchi

Keyword(s):

Unmanned Aerial Vehicle ◽

Control Method ◽

Low Cost ◽

Surface Inspection ◽

Physical Interaction ◽

External Disturbances ◽

Aerial Vehicle ◽

Passivity Based Control ◽

The Stability ◽

First Time

This paper proposes the use of a novel control method based on interconnection and damping assignment–passivity-based control (IDA-PBC) in order to address the aerial physical interaction (APhI) problem for a quadrotor unmanned aerial vehicle (UAV). The apparent physical properties of the quadrotor are reshaped in order to achieve better APhI performances, while ensuring the stability of the interaction through passivity preservation. The robustness of the IDA-PBC method with respect to sensor noise is also analyzed. The direct measurement of the external wrench, needed to implement the control method, is compared with the use of a nonlinear Lyapunov-based wrench observer and advantages/disadvantages of both methods are discussed. The validity and practicability of the proposed APhI method is evaluated through experiments, where for the first time in the literature, a lightweight all-in-one low-cost force/torque (F/T) sensor is used onboard of a quadrotor. Two main scenarios are shown: a quadrotor responding to external disturbances while hovering (physical human–quadrotor interaction), and the same quadrotor sliding with a rigid tool along an uneven ceiling surface (inspection/painting-like task).

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Alterations in the mechanical, chemical and biocompatibility properties of low-cost polyethylene and polyester meshes after steam sterilization

Hernia ◽

10.1007/s10029-020-02272-w ◽

2020 ◽

Vol 24 (6) ◽

pp. 1345-1359 ◽

Cited By ~ 1

Author(s):

Reiko Wiessner ◽

R. Lorenz ◽

A. Gehring ◽

T. Kleber ◽

C. Benz ◽

...

Keyword(s):

Melting Point ◽

Low Cost ◽

Tensile Force ◽

Human Fibroblasts ◽

Chemical Properties ◽

Tensile Tests ◽

Steam Sterilization ◽

Tensile Forces ◽

Mechanical Tensile ◽

And Chemical Properties

Abstract Introduction In Africa and other Low Resource Settings (LRS), the guideline-based and thus in most cases mesh-based treatment of inguinal hernias is only feasible to a very limited extent. This has led to an increased use of low cost meshes (LCMs, mostly mosquito meshes) for patients in LRS. Most of the LCMs used are made of polyethylene or polyester, which must be sterilized before use. The aim of our investigations was to determine changes in the biocompatibility of fibroblasts as well as mechanical and chemical properties of LCMs after steam sterilization. Material and methods Two large-pored LCMs made of polyester and polyethylene in a size of 11 x 6 cm were cut and steam sterilized at 100, 121 and 134 °C. These probes and non-sterile meshes were then subjected to mechanical tensile tests in vertical and horizontal tension, chemical analyses and biocompatibility tests with human fibroblasts. All meshes were examined by stereomicroscopy, scanning electron microscopy (SEM), LDH (cytotoxicity) measurement, viability testing, pH, lactate and glycolysis determination. Results Even macroscopically, polyethylene LCMs showed massive shrinkage after steam sterilization, especially at 121 and 134 °C. While polyester meshes showed no significant changes after sterilization with regard to deformation and damage as well as tensile force and stiffness, only the unsterile polyethylene mesh and the mesh sterilized at 100 °C could be tested mechanically due to the shrinkage of the other specimen. For these meshes the tensile forces were about four times higher than for polyester LCMs. Chemical analysis showed that the typical melting point of polyester LCMs was between 254 and 269 °C. Contrary to the specifications, the polyethylene LCM did not consist of low-density polyethylene, but rather high-density polyethylene and therefore had a melting point of 137 °C, so that the marked shrinkage described above occurred. Stereomicroscopy confirmed the shrinkage of polyethylene LCMs already after sterilization at 100 °C in contrast to polyester LCMs. Surprisingly, cytotoxicity (LDH measurement) was lowest for both non-sterile LCMs, while polyethylene LCMs sterilized at 100 and 121 °C in particular showed a significant increase in cytotoxicity 48 hours after incubation with fibroblasts. Glucose metabolism showed no significant changes between sterile and non-sterile polyethylene and polyester LCMs. Conclusion The process of steam sterilization significantly alters mechanical and structural properties of synthetic hernia mesh implants. Our findings do not support a use of low-cost meshes because of their unpredictable properties after steam sterilization.

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Design, Analysis, and Verification of an Electro- Hydrostatic Actuator for Distributed Actuation System

Sensors ◽

10.3390/s20030634 ◽

2020 ◽

Vol 20 (3) ◽

pp. 634 ◽

Cited By ~ 2

Author(s):

Yang Li ◽

Zongxia Jiao ◽

Zimeng Wang

Keyword(s):

Phase Difference ◽

Dynamic Characteristics ◽

High Efficiency ◽

Control Method ◽

Low Cost ◽

Detailed Structure ◽

Actuation System ◽

And Control ◽

Valve Control ◽

Direct Pump

In order to provide a simplified and low-cost solution of the terminal for a distributed actuation system, this paper proposes an electro-hydrostatic actuator (EHA) based on the linear drive principle. The proposed actuator is directly driven by a linear pump with a collaborative rectification mechanism, whose performance relies on the collaboration of the internal two units. A pair of linear oscillating motors are employed to drive the two pump units respectively. The control of the actuator is based on the modulation of the oscillating amplitude, frequency, and phase difference of the two motors. The advantage of this actuator is that no more valve control is needed to rectify the linear pump besides the high efficiency of the direct pump drive. In this paper, both schematic and detailed structure of the actuator is presented. The kinematic and dynamic characteristics are analyzed and modeled, based on which the control method is proposed. The experiments verify the validity of the actuator structure and control.

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Low-Cost Position Sensorless Speed Control of PMSM Drive Using Four-Switch Inverter

Energies ◽

10.3390/en12040741 ◽

2019 ◽

Vol 12 (4) ◽

pp. 741 ◽

Cited By ~ 5

Author(s):

Omer Kivanc ◽

Salih Ozturk

Keyword(s):

Control Method ◽

Low Cost ◽

Experimental Studies ◽

Speed Control ◽

Estimation Algorithm ◽

Phase Lock Loop ◽

Pass Filter ◽

Low Pass Filter ◽

Current Controller ◽

Position Sensorless

A low-cost position sensorless speed control method for permanent magnet synchronous motors (PMSMs) is proposed using a space vector PWM based four-switch three-phase (FSTP) inverter. The stator feedforward d q -axes voltages are obtained for the position sensorless PMSM drive. The q-axis current controller output with a first order low-pass filter formulates the rotor speed estimation algorithm in a closed-loop fashion similar to PLL (Phase Lock Loop) and the output of the d-axis current controller acts as the derivative representation in the stator feedforward voltage equation. The proposed method is quite insensitive to multiple simultaneous parameter variations such as rotor flux linkage and stator resistance due to the dynamic effects of the PI current regulator outputs that are used in the stator feedforward voltages with a proper value of K gain in the q-axis stator voltage equation. The feasibility and effectiveness of the proposed position sensorless speed control scheme for the PMSM drive using an FSTP inverter are verified by simulation and experimental studies.

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Investigation of partially bonded fiber-reinforced elastomeric isolators (PB-FREIs) with nominal vertical tensile loads

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2018-0014 ◽

2019 ◽

Vol 46 (8) ◽

pp. 669-676 ◽

Cited By ~ 1

Author(s):

Niel C. Van Engelen ◽

Michael J. Tait ◽

Dimitrios Konstantinidis

Keyword(s):

Seismic Isolation ◽

Low Cost ◽

Compressive Load ◽

Polymer Fibers ◽

Experimental Investigations ◽

Loading Conditions ◽

Fiber Reinforced ◽

Conventional Steel ◽

Tensile Forces ◽

The Cost

Unbonded fiber-reinforced elastomeric isolators (FREIs) were initially proposed as a potential low-cost alternative to conventional steel-reinforced elastomeric isolators (SREIs). FREIs are similar to SREIs but comparatively lightweight as the steel components from SREIs have been replaced with polymer fibers in FREIs. Subsequent experimental investigations identified that unbonded FREIs have desirable characteristics for seismic isolation due to the unbonded application and fiber reinforcement. The unbonded application removes mechanical fasteners, relying on friction to transfer horizontal loads, further reducing the cost. However, the unbonded application also introduces limitations, being susceptible to slip in certain loading conditions and being incapable of resisting tensile forces. In this paper, the concept of partially bonded FREIs (PB-FREIs), a proposed solution to these limitations, is further investigated experimentally with nominal vertical tensile loads. It is shown that PB-FREIs can achieve similar properties to an unbonded FREI with a vertical compressive load.

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