Operation Principle Research Articles

AUTOMATION OF FORKLIFT TRUCK SLEWING MECHANISM

This article considers the problem of warehouse automation, offers its solutions based on the analysis of existing approaches and techniques in the field of unmanned material handling machines. The structural scheme of forklift truck and turning mechanism, which becomes the basis for modernization of the machine, is described in detail. The description of the mechanism operation and the way of its control is given, and also the hydraulic scheme of the machine units control is displayed taking into account the improvement of the forklift design, the principle of the mechanism operation and the hydraulic scheme is described, the comparative analysis of the chosen way of warehouse automation in relation to other existing ones is formulated, the conclusions about the corresponding changes in the forklift design are presented in the conclusion, the image of the operator's console of the automated forklift is given.

РАЗРАБОТКА МОДЕЛИ ФИЗИЧЕСКОГО ПРИНЦИПА ДЕЙСТВИЯ СИСТЕМЫ АВТОМАТИЧЕСКОГО РЕГУЛИРОВАНИЯ ПОДАЧИ ТОПЛИВА ДИЗЕЛЬНОГО ДВИГАТЕЛЯ

The article discusses the use of an engineering-physical method for automatically regulating fuel supply in a diesel engine at the stage of constructing a model of the physical principle of operation. The resulting model of the system allows us to display the movement of the working fluid in space and its physical interaction in time.

Direct air capture capacity configuration and cost allocation based on sharing mechanism

Direct air capture (DAC) offers a potential solution for capturing carbon dioxide directly from the atmosphere, making it a promising technology in the field of negative carbon solutions. However, its current stage is characterized by high costs and a lack of maturity, placing it in the early phases of commercial application. To address these challenges, this paper introduces a novel cost-sharing mechanism specifically designed for DAC equipment within the context of carbon emission management in power systems. The aim is to facilitate both DAC capacity configuration and cost allocation. We begin by dissecting the operational principles of DAC and reviewing ongoing demonstration projects. We then pioneeringly devises a unified operational model (UOM) for DAC, which integrates electricity and carbon considerations seamlessly. Following this, we introduce an enhanced version of the carbon emission flow (CEF) theory, customized for DAC deployment. This sets the stage for the design of a DAC-specific carbon capture cost-sharing mechanism. Building on these foundations, we develop a meticulous DAC capacity planning model. This is accompanied by a cost allocation methodology based on the Shapley value framework. The ultimate goal is equitable cost allocation among stakeholders and optimized DAC capacity planning. Case studies validate the efficacy of both the proposed model and the cost allocation methodology. The insights from this study contribute to advancing theoretical frameworks for carbon capture technologies and have practical implications for engineering designs in real-world implementation.

Harvesting the power of the oceans: Advancements, challenges, and the promising future of wave energy

This dissertation explores the pivotal domain of wave energy, delving into its historical evolution, technological advancements, and economic prospects. In response to escalating environmental challenges and the imperative to address climate change, the pursuit of sustainable and ecologically benign energy sources has gained prominence. Wave energy emerges as a compelling frontier within the realm of renewable energy, tapping into the perpetual undulations of oceans. The study traces the conceptual antecedents of wave energy from the 19th century to its current status as a burgeoning renewable energy source. Significant strides in technology during the 1990s and 2010s marked a shift towards optimizing energy conversion efficiencies, exploring novel materials, and refining wave energy converter designs. The dissertation analyzes diverse wave energy converter types, their operational principles, and their potential applications. Despite challenges such as environmental impact, operational reliability, and high capital costs, the unwavering commitment of researchers positions Wave Energy as a sanguine contender in the renewable energy landscape. The economic outlook for wave energy is promising, with global potential estimated at 2 billion kilowatts, fostering socio-economic benefits and contributing to carbon emission reduction. By presenting a comprehensive examination of wave energy, this dissertation underscores its significance in the pursuit of sustainable, environmentally friendly, and reliable energy solutions.

A critical review of transitioning from conventional actuators to artificial muscles in upper-limb rehabilitation devices

Brain injuries resulting from spinal cord injuries, strokes, or cerebral palsy are among the traumas most capable of compromising the motor activities of human limbs, hence the necessity for the development of exoskeletons dedicated to the rehabilitation of these organs. This review examines the landscape of actuators essential for the design of cutting-edge upper-limb rehabilitation exoskeletal structures. Beyond merely surveying the current types of actuators available, the paper aims to provide guidelines for selecting actuators that fit optimally with the objectives of upper-limb rehabilitation. The description starts with a brief discussion on the biomechanics of the upper limbs, focusing on the kinematics of pivotal joints (wrist, elbow, shoulder). Subsequently, the existing actuators are systematically reviewed, offering detailed insights into their primary features, operational principles, strengths, weaknesses, and noteworthy applications within the realm of rehabilitation robotics. After the discussion about the actuators, the paper advances by furnishing valuable guidelines for actuators’ selection tailored for upper limb rehabilitation. These guidelines discuss crucial factors, such as the forces required and the natural Range Of Motions (ROMs) of upper limb joints. Finally, the manuscript serves as a valuable resource for researchers, engineers, and practitioners involved in the development of innovative upper-limb rehabilitation devices.

Shunt options for normal pressure hydrocephalus: a comparison of complications, overdrainage rates and neurological outcomes between integra low flow regulated and Codman Hakim programmable shunts

Aims: Shunt surgery is the most commonly performed treatment for idiopathic normal pressure hydrocephalus, and shunt systems with different operating principles are employed. This study aimed to retrospectively compare programmable ventriculoperitoneal shunts and flow-regulated shunts in terms of complications, overdrainage rates, and neurological outcomes. Methods: Between January 2020 and May 2022, 44 patients who underwent shunt operation with a diagnosis of idiopathic normal pressure hydrocephalus at our clinic were retrospectively analyzed. Patients were categorized into two groups: the programmable ventriculoperitoneal shunt and the flow-regulated shunt group. Demographic characteristics, complications, rates of insufficient drainage/overdrainage, and surgical outcomes were compared. Results: There were 26 patients in the programmable ventriculoperitoneal shunt group and 18 patients in the flow-regulated shunt group. In the programmable ventriculoperitoneal shunt group, 14 patients (53.8%) required 27 shunt setting adjustments owing to excessive or inadequate drainage. Subdural effusion was observed in five patients (19.2%), and shunt revision was performed in one patient (3.8%). Subdural effusion was observed in two (11.1%) patients in the flow-regulated shunt group. One of these patients (5.5%) underwent shunt revision. There was no significant difference between the groups in terms of the development of subdural effusion and need for shunt revision (p>0.05). The rate of improvement in at least one of the symptoms was 53.8% in the programmable ventriculoperitoneal shunt group at the 1st-month postoperative outpatient follow-up. In the flow-regulated shunt group, this rate was 72.2% and there was no statistically significant difference. Both groups showed similar clinical improvement at the 1-year follow-up. Conclusion: There was no difference between the groups in terms of neurological outcomes and the need for shunt revision. However, the use of flow-regulated shunts has demonstrated earlier rates of clinical improvement without the need for reprogramming.

Review of Energy Storage Capacitor Technology

Capacitors exhibit exceptional power density, a vast operational temperature range, remarkable reliability, lightweight construction, and high efficiency, making them extensively utilized in the realm of energy storage. There exist two primary categories of energy storage capacitors: dielectric capacitors and supercapacitors. Dielectric capacitors encompass film capacitors, ceramic dielectric capacitors, and electrolytic capacitors, whereas supercapacitors can be further categorized into double-layer capacitors, pseudocapacitors, and hybrid capacitors. These capacitors exhibit diverse operational principles and performance characteristics, subsequently dictating their specific application scenarios. To make informed decisions in selecting capacitors for practical applications, a comprehensive knowledge of their structure and operational principles is imperative. Consequently, this review delved into the structure, working principles, and unique characteristics of the aforementioned capacitors, aiming to clarify the distinctions between dielectric capacitors, supercapacitors, and lithium-ion capacitors.

Gas-liquid countercurrent flow characteristics in a microbubble column reactor

Countercurrent flow mode is widely utilized in many chemical unit operations due to its effective enhancement of mass transfer driving force. While the microbubble column reactor has garnered attention for its substantial gas–liquid specific surface area and fast mass transfer rate under the concurrent flow condition, countercurrent flow microbubble column reactors remain relatively underexplored. Consequently, in this study a novel microbubble generator device featuring gas–liquid co-crossing a microfiltration membrane was developed. This device could generate microbubbles with narrow size distribution, and proved suitable for integration into the countercurrent microbubble column reactor. Further investigation ensued to elucidate the operational principles of this dispersion method. Finally, the hydrodynamic behavior of the countercurrent microbubble column reactor was examined. Remarkably, a gas–liquid-specific surface area 2300 m2/m3 was reached, surpassing that of conventional bubble column reactors by a significant margin. New gas–liquid chemical processes and process intensification technologies could be developed accordingly.

Origami single-end capacitive sensing for continuous shape estimation of morphing structures

In this work, we propose a novel single-end morphing capacitive sensing method for shape tracking, FxC, by combining Folding origami structures and Capacitive sensing to detect the morphing structural motions using state-of-the-art sensing circuits and deep learning. It was observed through embedding areas of origami structures with conductive materials as single-end capacitive sensing patches, that the sensor signals change coherently with the motion of the structure. Different from other origami capacitors where the origami structures are used in adjusting the thickness of the dielectric layer of double-plate capacitors, FxC uses only a single conductive plate per channel, and the origami structure directly changes the geometry of the conductive plate. We examined the operation principle of morphing single-end capacitors through 3D geometry simulation combined with physics theoretical deduction, which deduced similar behavior as observed in experimentation. Then a software pipeline was developed to use the sensor signals to reconstruct the dynamic structural geometry through data-driven deep neural network regression of geometric primitives extracted from vision tracking. We created multiple folding patterns to validate our approach, based on folding patterns including Accordion, Chevron, Sunray and V-Fold patterns with different layouts of capacitive sensors using paper-based and textile-based materials. Experimentation results show that the geometry primitives predicted from the capacitive signals have a strong correlation with the visual ground truth with R-squared value of up to 95% and tracking error of 6.5 mm for patches. The simulation and machine learning constitute two-way information exchange between the sensing signals and structural geometry. By embedding part of the origami surface with morphing single-end capacitive sensors, FxC presents a unique solution that leverages both the mechanical properties of origami and sensing properties of capacitive sensing.

Whole-field principal angle and optical path retardation measurements using white light OPD scanning polariscope with first moment algorithm

White-light Optical Path Difference (OPD) scanning polariscope is currently an accepted technique for analyzing photoelastic specimens. While it has proven effective in overcoming limitations associated with phase-stepping and fringe scanning techniques, it is constrained when evaluating optical path retardation smaller than the light source coherence length. To address this limitation, a white-light OPD scanning polariscope, equipped with a first moment algorithm, has been introduced for the comprehensive examination of whole-field principal angle and optical path retardation. This article demonstrates the design and operational principles of the proposed polariscope, details an experimental setup for its deployment, and presents findings from practical applications of this setup. The results confirm the effectiveness and practicality of the proposed polariscope. Furthermore, these results highlight its precision, with standard deviations of 0.176° for principal angle and 6.4 nm for optical path retardation measurements.

A new single magnetic core coupled-inductor based active switched Quasi Z-source inverter

This paper presents a novel topology for Z-source inverters (ZSI). The new Z-Source network is based on the coupled-inductors and active switched boost. Features of the topology include high voltage boost ability, single magnetic-core, low voltage stress on the active switch, and capacitors. The principles of operation, analysis, voltage and current equations of each component, and the converter voltage gain in the steady-state are presented. A comparison with other topologies has also been performed to determine the advantages and disadvantages of the proposed ZSI. Finally, experimental results of the laboratory prototype are presented to confirm the performance of the proposed topology.

Polymer Materials for Optoelectronics and Energy Applications.

This review comprehensively addresses the developments and applications of polymer materials in optoelectronics. Especially, this review introduces how the materials absorb, emit, and transfer charges, including the exciton-vibrational coupling, nonradiative and radiative processes, Förster Resonance Energy Transfer (FRET), and energy dynamics. Furthermore, it outlines charge trapping and recombination in the materials and draws the corresponding practical implications. The following section focuses on the practical application of organic materials in optoelectronics devices and highlights the detailed structure, operational principle, and performance metrics of organic photovoltaic cells (OPVs), organic light-emitting diodes (OLEDs), organic photodetectors, and organic transistors in detail. Finally, this study underscores the transformative impact of organic materials on the evolution of optoelectronics, providing a comprehensive understanding of their properties, mechanisms, and diverse applications that contribute to advancing innovative technologies in the field.

Global regularity for critical SQG in bounded domains

AbstractWe prove the existence and uniqueness of global smooth solutions of the critical dissipative SQG equation in bounded domains in . We introduce a new methodology of transforming the single nonlocal nonlinear evolution equation in a bounded domain into an interacting system of extended nonlocal nonlinear evolution equations in the whole space. The proof then uses the method of the nonlinear maximum principle for nonlocal operators in the extended system.

Imaging the Lung in ARDS: A Primer.

Despite periodic changes in the clinical definition of ARDS, imaging of the lung remains a central component of its diagnostic identification. Several imaging modalities are available to the clinician to establish a diagnosis of the syndrome, monitor its clinical course, or assess the impact of treatment and management strategies. Each imaging modality provides unique insight into ARDS from structural and/or functional perspectives. This review will highlight several methods for lung imaging in ARDS, emphasizing basic operational and physical principles for the respiratory therapist. Advantages and disadvantages of each modality will be discussed in the context of their utility for clinical management and decision-making.

Compact lab-on-printed circuit board (PCB) for free-surfactant silver nanomaterial synthesis

This study introduces a compact Lab-on-Printed Circuit Board (PCB) device featuring thermal integrated microfluidic channels designed for nanoparticle synthesis. Commonly, complex heating chambers are employed to expedite reactions and enhance nanomaterial productivity, yet they pose challenges in temperature control and mixing rates within the reaction chamber. To address these issues, we propose a compact device composed of PDMS microfluidic channels and a PCB platform. The PCB heater, constructed to precisely regulate temperature within the microfluidic channels, utilizes copper lines as heating resistors, while an Arduino kit is employed for temperature measurement and control. Leveraging a Proportional–integral–derivative (PID) controller through programming, the device achieves rapid temperature increase and stable control within the microfluidic channels. Experimental validation demonstrates the operational principles and capabilities of this device, showcasing observable changes in nanoparticle size and morphology. Discussions on these observed results are included in this work.

Improved Design of a SiC MOSFET Gate Drive with Crosstalk Suppression Capability

For high-frequency switching applications, silicon carbide (SiC) devices are more suitable than silicon-based devices, which is conducive to improving the efficiency and power density of power electronic equipment. However, as the switching frequency increases, the influence of parasitic parameters on the switching characteristics of devices becomes increasingly apparent. When SiC metal-oxide-semiconductor field-effect transistors (MOSFETs) are applied in bridge circuits, the crosstalk problem easily occurs with the complementary conduction of upper and lower transistors, which seriously limits the promotion of SiC MOSFETs. However, the existing crosstalk suppression drive circuit tends to increase the switching loss, switching delay, and control complexity; therefore, a gate drive with crosstalk suppression capability is proposed. In this paper, the gate drive has two features: a negative voltage to shut down the SiC MOSFET; and an adjustment of the gate-source equivalent impedance. To accomplish this goal, the mechanism of crosstalk voltage generation is analyzed. Furthermore, the operation principle of the gate drive is analyzed, and the parameters of the gate drive are designed. Eventually, the proposed gate drive is verified by an LTspice simulation and experimental platform. The results prove that the gate drive can suppress the crosstalk voltage without affecting the switching speed.

STRUCTURE FEATURES OF MINIMUM FREQUENCY SHIFT KEYING SIGNAL MODEMS

The article discusses specific features of constructing modems for minimum frequency shift keying signals using various schemes with high noise immunity levels. An analysis of the formation of these signals and frequency modulation signals, which are orthogonal if enhanced, is provided, including quantitative indicators and comparative characteristics. Two schemes of minimum frequency shift keying signal demodulators (coherent and autocorrelation) are examined, including their comparative features. Operation principles of these demodulator circuits with the use of timing diagrams are described, requirements for the reference oscillator generators included in coherent demodulators are formulated, as well as the requirements for minimum frequency shift keying signals, which ensure the greatest noise immunity in autocorrelation demodulators of minimum frequency shift keying signals with binary signals quantization.

Overview of motors for heavy drones

The article is devoted to an overview of engines used in heavy drones. The main types of engines, their principles of operation, advantages and disadvantages are considered. The article examines a wide range of electric motors, such as brushless DC (collectorless) motors, which are the main components in modern quadcopters. Types of engines, their technical characteristics, as well as their use in specific models of quadcopters are also considered. This article will help you better understand the specifics of different types of motors and how they affect quadcopter functionality and performance.

3D Simulation-Driven Design of a Microfluidic Immunosensor for Real-Time Monitoring of Sweat Biomarkers.

This study presents the design and comprehensive 3D multiphysics simulation of a novel microfluidic immunosensor for non-invasive, real-time detection of pro-inflammatory biomarkers in human sweat. The patch-like device integrates magnetofluidic manipulation of antibody-functionalized magnetic nanoparticles (MNPs) with direct-field capacitive sensing (DF-CS). This unique combination enhances sensitivity, reduces parasitic capacitance, and enables a more compact design compared to traditional fringing-field approaches. A comprehensive 3D multiphysics simulation of the device, performed using COMSOL Multiphysics, demonstrates its operating principle by analyzing the sensor's response to changes in the dielectric properties of the medium due to the presence of magnetic nanoparticles. The simulation reveals a sensitivity of 42.48% at 85% MNP occupancy within the detection zone, highlighting the sensor's ability to detect variations in MNP concentration, and thus indirectly infer biomarker levels, with high precision. This innovative integration of magnetofluidic manipulation and DF-CS offers a promising new paradigm for continuous, non-invasive health monitoring, with potential applications in point-of-care diagnostics, personalized medicine, and preventive healthcare.

New Measuring and Data Transmission Equipment for Operational Oceanography at the Gelendgik Black Sea Test Site of Institute of Oceanology of the RAS

The design and principles of operation of the bottom multi-modem station MDS-II, located in the coastal zone (depth of location — 25 m) of the northeastern part of the Black Sea at the Gelendzhik Test Site of IO RAS are described. The station is connected to the coastal center by means of a bottom fiber-optic cable, through which power is supplied to the station, and online transmission of measurement data takes place. The station is an underwater server to which one can connect a measuring device and get a real-time access to it, as well as remotely control on its operation. The design of an automatic stationary station for vertical sounding (SSVS) of water column, which is also used at the Gelendzhik Test Site, is also described. This station is installed close to the MDS-II multi-modem station and is connected to one of its modems. The station consists of a bottom electric winch installed on the seabed and a floating module (probe) on a cable line wound around the winch drum. When the command ʺsoundingʺ is given, the cable unwinds and the floating module, equipped with temperature and pressure sensors, floats and measures the water temperature profile from the bottom layer to the sea surface. Then the cable is winding on a drum, and the floating module returns to the bottom layer. A prototype of a new SSVS is being developed, which will allow sounding of the water layer with a thickness of up to 100 m. It will be equipped with a multi-parameter probe that makes joint measurements of hydrophysical and bio-optical parameters.