Principle Of Conversion Research Articles

Research Progress on Photothermal Therapy of Malignant Tumor Cells

Malignant tumors, also known as cancer, are among the diseases with the highest incidence and mortality rates in the world. Photothermal therapy (PTT) involves injecting materials with high photothermal conversion efficiency (PTA) into the human body and using the principle of photothermal conversion to kill malignant tumor cells at the lesion site with high temperatures. This paper reviews various methods of photothermal therapy for malignant tumors, summarizes the basic therapeutic logic of photothermal therapy, and forecasts the future development prospects of this treatment method.

Vibrothermography for NDT : dynamic control of thermal sources by acoustic fields

Among the plethora of Non-Destructive Evaluation (NDE) techniques, the coupling of acoustic/vibration and thermography has emerged as a powerful method, more particularly denoted as sonothermography, utilizing the principle of energy conversion from acoustic waves to thermal heat sources to reveal structural abnormalities or create tunable volumic sources in materials. The calculation of the displacement field induced by acousto-vibrational excitations, using the analytical expression of energy conversion, has led to the generation and modeling of localized thermal sources in space over time within a material. By manipulating the input parameters of acoustic signals (frequency, phase, amplitude), we have demonstrated that it is possible to strategically position these sources in space and optimize the dissipation of thermal energy. The variation of parameters (creating a phase shift, a beat, a reversal law, etc.) makes it possible to control and move these internal heat sources to scan the material (in numerical approach and in the near future experimentally). The analysis of the resulting fields (acoustic-vibration and thermal), using inverse methods, opens up new possibilities for measuring the physical properties (mechanical, thermal) or characterizing defects in a material.

Piezoelectric Energy Harvesting for Civil Engineering Applications

This work embarks on an exploration of piezoelectric energy harvesting (PEH), seeking to unravel its potential and practicality. PEH has emerged as a promising technology in the field of civil engineering, offering a sustainable approach to generating energy from ambient mechanical vibrations. We will explore the applications and advancements of PEH within the realm of civil engineering, focusing on publications, especially from the years 2020 to 2024. The purpose of this study is to thoroughly examine the potential and practicality of PEH in civil engineering applications. It delves into the fundamental principles of energy conversion and explores its use in various areas, such as roadways, railways, bridges, buildings, ocean wave-based energy harvesting, structural health monitoring, and even extraterrestrial settings. Despite the potential benefits of PEH in these domains, there are significant challenges that need to be addressed. These challenges include inefficient energy conversion, limitations in scalability, concerns regarding durability, and issues with integration. This review article aims to address these existing challenges and the research gap in the piezoelectric field.

KESANTUNAN BERBAHASA DALAM KOMENTAR AKUN INSTAGRAM “BAWASLU RI” SEBAGAI BAHAN AJAR TEKS ANEKDOT KELAS X

Language is a communication tool that one can use to convey their feelings and desires. Therefore, language functions as a tool to convey what is implied in one's mind. In the context of showing awareness of the dignity of others in language, either directly or indirectly, is known as language politeness. there is a violation and compliance of the principle of politeness or courtesy in a comment. Where at the time of commenting, the speaker feels free to give an utterance of positive or negative criticism. In giving an utterance must pay attention to the principles of conversation. The qualitative approach applied in this study emphasizes an in-depth understanding of the phenomenon under study. The data obtained are not in the form of numbers, but words that reflect the thoughts and experiences of the subject. This research was conducted using qualitative descriptive method. Based on the contextual research that refers to analysis, what is meant by descriptive in this research is the description of the objectives and formulation of the problem of how the principles of language politeness in the comments of Bawasli RI's Instagram account involve pragmatic theory from the study of the principles of language politeness according to Leech. The results of this study include two things that are in accordance with the formulation of the problem and the objectives of the research discussed, namely 1) The form of adherence to the principle of politeness is.

Mechanism Exploration of the Photoelectrochemical Immunoassay for the Integration of Radical Generation with Self-Quenching.

Photoelectrochemical (PEC) sensing mechanisms based on enzyme-catalyzed strategies primarily achieve the quantitative analysis of biomolecules through the enhancement or attenuation of photocurrent signals. However, there are still no reports that delve into the principles of photocurrent signaling conversion in the reaction between photoactive materials and the biomolecules. In this work, we demonstrated that indium oxysulfide InOS-0.5 heterojunction has excellent peroxidase activity to catalyze the reaction of H2O2-generated hydroxyl radicals (•OH) with the self-generated electrons, thereby resulting in synergistic quenching of the photocurrent signal. Based on the above principles, we coupled InOS-0.5 with a sandwich-type immunoassay to introduce H2O2 production catalyzed by glucose oxidase for the development of a PEC immunosensing platform. H2O2 reacted with InOS-0.5 to produce •OH with strong oxidizing properties, thus quenching the photogenerated electrons and realizing the PEC detection of the carcinoembryonic antigen (CEA, as a model analyte). The photocurrent intensity decreases with the logarithmic increase in CEA concentration (0.02-50 ng mL-1), with a remarkable limit of detection of 8.9 pg mL-1 (S/N = 3). This study further investigates the mechanism of hydrogen peroxide-induced photocurrent quenching, providing deeper insights into the mechanisms of electron-hole transport in hollow porous semiconductor materials and paving the way for the development of efficient PEC sensors.

Flouting Conversational Maxims In The Rom-Com Movie The Kissing Booth 2

To create effective communication, individuals must adhere to the four conversational maxims or principles of cooperation. However, in the world of movies, language use tends to be more varied, and sometimes not subject to the norms of language politeness and the context of language use. As a result, the information conveyed can be unclear and ambiguous, which in turn leads to violations of the conversational maxims. The purpose of this study is to analyze the types of flouting maxims found in The Kissing Booth 2 Movie and to identify the reasons behind the flouting maxim since it is very important to make communication as effective as possible. In this study, the researcher used a theory proposed by Grice in Levinson in analyzing the types of flouting maxims and the theory proposed by Leech in analyzing the reason behind the flouting maxim that occurs in the movie. This study used a descriptive qualitative method to provide a deeper understanding of the flouting maxim and the reasons for flouting. The data were collected from the conversations that occurred among the characters in The Kissing Booth 2 Movie. The results found that there were violations of the maxims of quantity, quality, relevance, and manner committed by the characters. Relevance violations are less frequent (8.3%) and typically occur when characters fail to shift topics in response to specific questions. Intriguingly, maxim violations do not invariably yield negative outcomes, as characters collaborate to convey their intended meanings smoothly. This collaborative approach is particularly prevalent (65%), signifying that characters often flout maxims when illocutionary goals diverge from social goals. Ultimately, the study concludes that the flouting maxim of quantity prevails, and collaborative reasons dominate as the most common motivation behind maxim deviations.

Multipoint Variable parameter compliant control of redundant manipulator based on the equivalent twin model of flexible contact dynamics

To elucidate the dynamic coupling mechanism involved in multipoint/arbitrary point contact during human–robot interactions with redundant manipulators, we introduce a compliant control strategy that adapts to variable parameters. This strategy is based on the flexible contact dynamic equivalent twin system for human–robot interactions. Using the Virtual Elastic Element Representation model for arbitrary point contact dynamics and leveraging the skeleton principle for contact force conversion, we construct a flexible contact dynamic equivalent twin system tailored for redundant manipulators with multipoint/arbitrary point contact capabilities. Within this system, we implement real-time adjustments to the impedance stiffness coefficient in conjunction with the virtual end velocity of the manipulator. We optimize the joint angular velocity of the manipulator while considering the motion allocation of redundant degrees of freedom. This optimization enables multipoint contact variable parameter compliance control for safe human–robot interactions. To validate our approach, we analyze the multipoint contact dynamic model of the redundant manipulator's interaction with humans and assess the feasibility of the variable parameter compliance control method using robot operating system simulations. Ultimately, we verify the effectiveness and practicality of our proposed compliance control method through simulation and experimental results.

Analysis of the Second-Order NS SAR ADC Performance Enhancement Based on Active Gain

This paper presents a novel second-order passive noise shaping (NS) successive approximation register (SAR) analog-to-digital converter (ADC) based on active gain. The proposed scheme achieves a further improvement in the signal-to-noise ratio (SNR) of the proposed NS SAR ADC by reducing the kT/C noise and the conversion rate. After having presented the conversion principle, the theoretical analysis of the performance enhancement based on noise and other considerations is presented.

Numerical Modeling and Analysis of Pendant Installation Method Dynamics Using Absolute Nodal Coordinate Formulation

Accurately simulating the deployment process of coupled systems in deep-sea environments remains a significant challenge. This study employs the Absolute Nodal Coordinate Formulation (ANCF) to dynamically model and analyze multi-body systems based on the Pendant Installation Method (PIM). Utilizing the principle of energy conversion, this study calculates the stiffness, generalized elastic forces, mass matrices, and Morison equation, formulating a motion equation for the dynamic coupling of nonlinear time-domain forces in cables during pendulum deployment, which is numerically solved using the implicit generalized-α method. By comparing the simulation results of this model with those from the catenary theory model, the advanced modeling capabilities of this model are validated. Lastly, the sensitivity of the multi-body system under various boundary conditions is analyzed. The results indicate that deployment operations are more effective in environments with strong ocean currents. Furthermore, upon comparing the impacts of structural mass and deployment depth on the system, it was found that deployment depth has a more significant effect. Consequently, the findings of this study provide a scientific basis for formulating subsequent optimization strategies.

Metapragmatic awareness development in Chinese Children: A conversational competence perspective

The current study investigates the development of metapragmatic awareness in conversational competence among Chinese children aged 4–12 years. Utilizing eight cartoons, children were engaged with a series of metapragmatic questions targeting violations of four maxims of cooperation. By assessing their performance in a task involving conversational principles, we explore the progression of their metapragmatic skills. The results shows i) The metapragmatic awareness in different age groups increased. The early school-age stage was the transitional period in the development of children's metapragmatic awareness. The development range of metapragmatic awareness did not continuously increase in the later school-age stage. ii) Metacognitive awareness was in the salient position in the preschool stage, and in the early school-age stage metarepresentational awareness was predominant. Three forms of metapragmatic awareness did not develop sequentially. iii) The Chinese paratactic language structures and their profound cultural backgrounds influenced children's performance of metapragmatic awareness. This research provides a new paradigm for developmental pragmatics and it has a certain value for the treatment and intervention of the children with pragmatic impairments.

Flexural performance of innovative thin-walled steel–timber composite floor slabs

A floor slab carries and distributes the floor load in a structure and is an important component that affects overall structural performance. Therefore, it is important to investigate the mechanical properties of such materials. In this study, flexural performance tests under static load are conducted for an innovative thin-walled steel–timber composite floor slab, and the failure mode, bearing capacity, stiffness, deflection, and strain development are investigated. The results show that the floor slab can be quickly assembled using self-tapping and wood screws and exhibits good flexural performance. Using ABAQUS finite-element software, the effects of the oriented-strand board (OSB) thickness, thin-walled–steel-plate height, steel strength, and boundary conditions on the flexural performance of composite floor slabs are investigated. Furthermore, based on the EN1995–1-1 code and equal-section conversion principle, the simplified beam-unit model is established for the theoretical calculation of the composite floor slab. The effective bending stiffness is calculated by considering the influence of the slip modulus of the connector, and the stress distribution law of the section is analysed. The results provide a reliable design basis and reference for the application of thin-walled steel–timber composite floor slabs in engineering practice.

Wind turbine gearbox oil temperature feature extraction and condition monitoring based on energy flow

Supervisory Control and Data Acquisition (SCADA) data is widely used for wind turbine gearbox condition monitoring (WTGCM) due to its easy access and low cost, thus ensuring the safe and reliable operation of wind turbine gearboxes. However, existing WTGCM methods based on SCADA overlook the fundamental thermal physics and sensor failure. To effectively address the challenges of weak feature generalization and numerous false alarms, we propose a highly robust WTGCM method based on energy flow. Firstly, based on the principles of thermal balance and wind energy conversion, a feature extraction method considering the physical change process of oil temperature is proposed. Secondly, the performance of different feature extraction methods is quantitatively analyzed using data evaluation criteria. The reasons why different feature extraction methods have different effects are revealed through dimensionality reduction analysis. Finally, we compare the proposed method with other feature extraction methods using four models to validate the excellent performance of the proposed method in the early fault warning. The results demonstrate that the proposed method reduces the average root mean square error by 18.21% during the healthy operation of the wind turbine gearboxes. Moreover, the proposed method performs excellently in early warning of mechanical and sensor faults, significantly reducing the number of false alarms. The average warning time for mechanical faults is 32.56 h earlier.

GENETIC SYNTHESIS OF HYBRID ELECTRO-MECHANICAL SYSTEMS FOR MOTOR-SPINDLE UNITS WITH ADAPTIVE SPATIAL STRUCTURE

The results of fundamental research carried out at the Department of Electromechanics of KPI named after Igor Sikorsky, it was established that the structural organization and evolution of arbitrary classes of technical systems that function on the principles of electromechanical energy conversion is determined by the principles and laws of genetically organized systems. Motor-spindles (M-Ш) also belong to the category of such systems. The energy and genetic core of technical systems with electromechanical energy converters is the active zone of the energy converter, which is a physical and information carrier of genetic information and the corresponding genetic code. The trend of creating multi-coordinate motor-spindle units with a spatially adaptive structure, designed to function as part of metalworking centers and machines with digital control systems, is analyzed. In genetically organized systems, the processes of structuring objects of any level of complexity are implemented on the basis of the elemental information base of genetic programs using genetic synthesis operators. From the point of view of the theory of genetic structure formation, spatial adaptation is the result of chromosomal transformations using the principles of hybridization, mutation, replication, and isomerism. The problem of synthesizing a hybrid multifunctional EM structure for motor-spindle units with a spatially adaptive modular structure was formulated and solved. A generalized genetic model of chromosomal synthesis of hybrid electromechanical modules of motor-spindle units according to a given function has been developed. The structural formulas of hybrid electromagnetic chromosomes, which determine the population structure of original technical solutions, have been determined. Based on the simulation results, the structures of spatially adaptive motor-spindle units with two-, three-, and four-coordinate movement of the working body were synthesized. Based on the results of the research, a genetic catalog was created, which serves as a system basis for the development of original technical solutions for motor-spindle units.

Real-time monitoring method for power system voltage based on optical voltage sensors

Abstract A real-time monitoring method for power system voltage based on optical voltage sensors is proposed to obtain transient voltage signals and achieve real-time tracking of instantaneous changes in electrical parameters of the power system accurately and effectively. Analyzing the topology principle of power system transformers clarifies the installation location of optical voltage sensors. By combining the measurement principle of optical voltage sensors, the electrical, optical modulation, and optical-electrical conversion of voltage signals are achieved, and the voltage signal of the power system is output. Using the short-time Fourier transform method to perform temporal processing on the output signal and obtaining a voltage signal sliding window based on wavelet packet decomposition, we set the normal range threshold of the voltage signal in the sliding window, combined with information entropy theory to extract key features of the voltage signal and achieve real-time monitoring of the power system voltage. The experimental results show that the proposed method can effectively obtain transient voltage signals of the power system, with an average detection accuracy of 92.61%, and the output voltage can be adjusted promptly to reflect the instantaneous changes in the power system voltage.

Mechanical mechanism of shear cavitating water jet dissociation of flake graphite

Abstract To obtain the mechanical mechanism of shear-type cavitation water jet dissociating flake graphite to improve the grinding technology of flake graphite, the motion state of flake graphite particles in shear-type cavitation water jet, the micro-jet impact process, the high-pressure elastic potential energy pressure release process, and the water wedge stretching process have been analyzed using the theory of hydraulic transport of liquid-solid two-phase, the theory of jets, the cavitation primordial principle, the principle of capacity conversion, and the water wedge action. The primary mechanical mechanism of shear cavitation water jet dissociation of flake graphite is collision friction effect, micro-jet impact, pressure release, and water wedge stretching effect, under these four kinds of loads individually or jointly, to achieve the purpose of removing the surface of flake graphite particles of the veinstone minerals to realize the dissociation of flake graphite. Moreover, the collision friction, pressure release, and water wedge stretching effects destroy the material under tensile stress to remove the veinstone minerals, and the micro-jet impact effect is the destruction of the material under compressive stress to remove the veinstone minerals.

Model experimental study on special frequency of hydraulic pump working condition headcover for ultra-high head pump-turbine

Abstract With the accelerated construction of pumped-storage power stations, high-head and high-capacity pumped-storage units are gradually becoming the mainstream of development. When operated on-site, the high-head and high-capacity pumped-storage units reflect the phenomenon of special frequency of the head cover vibration of the water pump, which has attracted widespread attention from the industry. In order to deeply reveal the flow mechanism of pumped-storage units, model experiments on the head cover were conducted through the similarity conversion principle between the model and the prototype. The experiment results show that the occurrence of specific frequency in the Head cover of the water pump during operation is due to the rotating flow separation in the vaneless area.

Flexible Ultrasonic‐Induced Wireless Energy Conversion Technology in Implantable Biomedicine

AbstractNumerous associated challenges arise with the advancement and continuous improvement of implantable medical devices, such as the frequent requirement for battery replacement. The flexible ultrasonic‐induced wireless energy conversion (UWEC) technology has garnered significant interest due to its superior energy transmission efficiency, safety, and biocompatibility compared to traditional electromagnetic wireless energy conversion technology. This paper provides a comprehensive review of the recent advancements in two types of flexible UWEC technologies, triboelectric nanogenerators, and piezoelectret nanogenerators, with a focus on their applications in implantable medical treatments. First, the energy conversion principles and general materials of flexible UWEC are presented. Then, the research and application of flexible UWEC devices are introduced in detail based on their medical functions. At the end of this review, perspectives and opportunities are discussed.

To the question of construction of welding inverter sources with a high power factor

Purpose. Design a power-factor-corrected, energy- and cost-efficient switchmode power supply for welding. Methodology. It is proposed to use the principle of direct conversion and to develop the "hybrid" power circuit consisting of a main power path using direct conversion and an auxiliary power path having a converter with an intermediate DC link with relatively low stored energy. Since a load to the welding power supply is the welding arc, its instantaneous power fluctuations during the mains voltage period essentially do not influence the welding process due to the thermal constant of the weld pool molten metal. Effective use of this features of the welding arc allows to optimize the power processing, reduce the amount of energy stored in the reactive elements of the circuit and improve the economical, mass and dimensional parameters of the supplies. Findings. A new power factor corrected switchmode power supply topology is proposed utilizing beforementioned principles of power processing. The algorithm for calculating the switching frequency of supply power switches is given. To confirm the adequacy of the developed provisions, an experimental sample of the power supply was created. Oscillograms of mains voltage and source current consumption and oscillograms in output current limitation mode are obtained. The results of experiments showed that the supply has a power factor > 0.94 in a wide range of powers. Originality. A distinctive feature of the supply is the absence of additional inductive components in the power path, a lower capacitance of the DC-link bulk capacitor and a simplified scheme for limiting its inrush current during initial charging. The supply has an increased open circuit voltage, independent of the mains voltage, which allows for easy arc ignition during manual arc welding. Practical value. Due to the increased power factor, the current drawn from the mains is 30 % to 45 % lower than that of widespread inverter supplies without a power factor corrector. These features allow to simultaneously use more power supply units with the same mains current load, and/or to provide stable welding in conditions of a "weak" mains.

Torque System Modeling and Electromagnetic Coupling Characteristics Analysis of a Midpoint Injection Type Bearingless Permanent Synchronous Magnet Motor

Taking the Midpoint Injection type Bearingless Permanent Magnet Synchronous Motor (MPI-BL-PMSM) as an object, to solve its problems of large torque pulsation and insufficient suspension force when adopting Midpoint Suspension Current Unilateral Injection (MPSC-UI), a Midpoint Suspension Current Bilateral Injection (MPSC-BI) solution is proposed. Based on the half-winding structure of MPI-BL-PMSM, and from the electromechanical energy conversion principle, the torque model for MPSC-BI solution is established. On this basis, the torque model for MPSC-UI method was derived. The correctness of the established torque mathematical models based on half-winding structure was verified through the finite element method (FEM), and the “dual-frequency” electromagnetic coupling characteristics of suspension current on electromagnetic torque were compared and analyzed from the perspectives of theoretical model and FEM simulation. The results indicate that the MPSC-BI method can effectively suppress or avoid the torque pulsation coupled by suspension current and can obtain about 1-time increase of controllable suspension force; the advantages of MPSC-BI solution in dynamic torque decoupling characteristics are demonstrated, while the only downside is that the coupling effect of torque current on radial suspension force is slightly greater than that of the MPSC-UI method.

Recent Advances in Development of Biosensors for Monitoring of Airborne Microorganisms.

The early detection of infectious microorganisms is crucial for preventing and controlling the transmission of diseases. This article provides a comprehensive review of biosensors based on various diagnostic methods for measuring airborne pathogens. This article aims to explore recent advancements in the field of biosensors tailored for the detection and monitoring of airborne microorganisms, offering insights into emerging technologies and their potential applications in environmental surveillance and public health management. The study summarizes the research conducted on novel methods of detecting airborne microorganisms using different biological sensors, as well as the application of signal amplification technologies such as polymerase chain reaction (PCR), immunoassay reactions, molecular imprinted polymers (MIP) technique, lectin and cascade reactions, and nanomaterials. Antibody and PCR detection methods are effective for specific microbial strains, but they have limitations including limited stability, high cost, and the need for skilled operators with basic knowledge of the target structure. Biosensors based on MIP and lectin offer a low-cost, stable, sensitive, and selective alternative to antibodies and PCR. However, challenges remain, such as the detection of small gas molecules by MIP and the lower sensitivity of lectins compared to antibodies. Additionally, achieving high sensitivity in complex environments poses difficulties for both methods. The development of sensitive, reliable, accessible, portable, and inexpensive biosensors holds great potential for clinical and environmental applications, including disease diagnosis, treatment monitoring, and point-of-care testing, offering a promising future in this field. This review presents an overview of biosensor detection principles, covering component identification, energy conversion principles, and signal amplification. Additionally, it summarizes the research and applications of biosensors in the detection of airborne microorganisms. The latest advancements and future trends in biosensor detection of airborne microorganisms are also analyzed.