Transmission Of Type Research Articles

Power Transmission Technology Using Wireless Network

In this paper, we have presented the concept of wireless transmission i.e. power transmission without using any type of the electrical conductor and/or wires. We have presented an idea that is discussed here about how electrical energy can be transmitted as microwaves so that to reduce the transmission, allocation and other types of losses. Such technique is known as Microwave Power Transmission (MPT). We have also presented and correlated several aspects with the currently available Power transmission systems to the related history of wireless power transmission systems and also the related developmental changes. The basic design, merits and demerits, applications of Wireless Power Transmission are also discussed . The paper describes the various types of WPT technologies; Inductive Coupling, Magnetic Resonance and Radio Frequency (RF) technology. It also discusses the advantages and shortfalls of each type. An extensive survey of past works was discussed. Results from the research findings showed that distance and conversion efficiency were limiting factors in implementing wireless transfer technology

Cultural transmission among hunter-gatherers

We examine from whom children learn in mobile hunter-gatherers, a way of life that characterized much of human history. Recent studies on the modes of transmission in hunter-gatherers are reviewed before presenting an analysis of five modes of transmission described by Cavalli-Sforza and Feldman [L. L. Cavalli-Sforza, M. W. Feldman, Cultural Transmission and Evolution: A Quantitative Approach (1981)] but not previously evaluated in hunter-gatherer research. We also present two modes of group transmission, conformist transmission, and concerted transmission, seldom mentioned in hunter-gatherer social learning research, and propose a unique mode of group transmission called cumulative transmission. The analysis of the additional modes of transmission indicated that cultural evolutionary signatures of vertical transmission, such as the conservation of cultural traits, have been underestimated because previous studies have seldom considered remote generations or distinguished intrafamilial from extrafamilial horizontal and oblique transmission. However, field data also indicate that hunter-gatherer children interacted with and learned from many nongenetically related individuals; about half of children’s and adolescents’ horizontal and oblique social learning came from nongenetically related individuals. Intimate living conditions of hunter-gatherers provide opportunities for group transmission, and ethnographic evidence presented demonstrates that at least three types of group transmission exist. All three forms of group transmission theoretically contribute to the conservation of culture, homogeneity of intracultural diversity, and high intercultural diversity. Analysis of additional modes of oblique and horizontal transmission and discussion of previous and unique modes of group transmission demonstrate the various mechanisms by which hunter-gatherer children learn and how cultures are conserved and contribute to cumulative culture.

Vibration source inversion-based fault diagnosis: approach and application

The gear transmission system of industrial equipment is characterized by a highly integrated structure, non-stationary operating conditions, and large loads. Therefore, the attenuation of fault signal characteristics and the complexity of operating conditions in gear transmission systems significantly affect the effectiveness of vibration signal-based fault diagnosis. This paper proposes a unified diagnostic framework based on vibration source inversion for two typical transmission component fault signal phenomena: meshing frequency modulation sidebands and equally spaced fault characteristic frequency interval harmonic clusters. This approach incorporates the vibration transfer path analysis of passive subsystems and identifies bearing dynamic forces, followed by their decomposition, reconstruction, and sensitive frequency band localization. It enables accurate diagnosis of complex gear transmission systems under non-stationary conditions with limited vibration testing. The effectiveness and advantages of this method over existing mainstream signal processing techniques are validated through actual cases of gear and weak bearing fault diagnosis on a complex planetary gear transmission system test bench.

Dynamic analysis of two-stage steering reducer for electric vehicle based on ROMAX

Abstract. With the rapid development of electric vehicles in the modern market, the efficiency and performance requirements of electric vehicle transmission systems are getting higher and higher. As an important part of the electric vehicle reducer, the steering reducer can make full use of the advantages of the two-stage deceleration transmission, achieve more efficient power transmission, and improve the acceleration performance and driving performance of electric vehicles. This paper aims to design a two-stage steering reducer for an electric vehicle, which adopts planetary gear transmission type. Firstly, the working principle of the electric vehicle steering reducer is analyzed, and the overall design scheme of the reducer is drawn up. Secondly, the transmission system parameters of the reducer are designed and calculated, including transmission ratio distribution, tooth number ratio calculation, etc. Secondly, the transmission structure of the reducer is designed, including input shaft, output shaft, first planetary gear train, second planetary gear train, reducer shell, bearing, etc., and the reducer model is drawn by three-dimensional software Solidworks. Finally, the strength and deformation check analysis of the two-stage reducer is carried out by using the finite element software ROMAX to evaluate the performance of the designed reducer under this working condition. The full text design has a certain reference, and can be applied to other electric vehicle reducer design to provide theoretical guidance.

A theoretical model of excess attenuation of acoustic signals propagating under cracked sea-ice landscapes.

The Arctic sheet is transitioning from a continuous cover of thick multi-year ice to a fragmented landscape of thin young ice. If the type of acoustic transmission allows repetitive interaction of rays with the sea surface, in the fragmented scenario acoustic rays will undergo a random sequence of reflections from water or sea-ice interfaces. Calm sea conditions in the water channels between the ice floes (leads) and the smooth, flat surface of the young ice bottom reduce scattering due to interface roughness, resulting only in scattering due to inhomogeneity in surface reflectivity. Using an idealized framework, this study investigates the extent to which the mid- to high-frequency underwater acoustic propagation is altered due to repetitive interactions of acoustic signals with a sea surface consisting of a random distribution of ice sheets and leads. An expression for the coherent field (the acoustic field averaged over an ensemble of realizations of sea-ice distributions) was derived from theory. Any deviation from a homogeneous surface condition (either by randomly adding ice slabs in a free ice surface or by including leads in a fully ice-covered sea surface) leads to an excess attenuation of the coherent field. Results are validated by numerical simulations.

Physics-informed and data-driven hybrid method for transmission accuracy design optimization of planetary roller screw mechanism

The planetary roller screw mechanism (PRSM) faces an ever-increasing precision transmission demand in current advanced equipment. The relationship between machining errors and transmission accuracy remains elusive due to the over-simplified physical models and small-sample experimental datasets. This work proposes a physics-informed and data-driven hybrid strategy for PRSM transmission accuracy evaluation and tolerance optimization. In the physical model, a PRSM transmission accuracy model is developed to calculate transmission error that considers 16 machining errors in eccentric, nominal diameter, pitch, flank angle, and roller consistency. In the dataset establishment, thread profile measurements and dynamic leadscrew inspections are conducted for the machining error and transmission accuracy data acquisition. A data augmentation approach combining the physical model with the generative adversarial network is utilized to predict travel deviation, variations, and axial backlash and estimate machining error contribution with the small-sample experimental dataset. It is firstly found that the roller consistency of nominal diameter significantly affects PRSM travel variation V2π with a 17.3 % importance value. With the developed framework, the key tolerances for screw, roller, nut, and roller consistency are optimized toward a typical precision transmission requirement using the non-dominated sorting genetic algorithm. It also provides a tolerance grade recommendation table with PRSM transmission accuracy level in engineering practice.

A Review Reliability and Availability Analysis of IEC 61850 Based Substation Communication Architectures

Modern Ethernet technology's high-speed capabilities enable efficient data transfer, and its leadership in the LAN space further distinguishes Ethernet as an intriguing communication method. For important substation automation applications to operate successfully, communications must meet cost, performance, and reliability requirements technology for substation automation management. The IEC 61850 standard was published by the International Electro-Technical Commission (IEC) to provide interoperability among enterprise substation automation systems for communication networks within power substations. This standard specifies Ethernet-based communication systems for substation automation systems (SAS). With the aid of Ethernet switches, Ethernet offers versatility in terms of configuring different designs. On the other hand, before using appropriate Ethernet architectures for critical applications in substations, they must be assessed for availability and reliability. This study uses the reliability block diagram (RBD) approach to analyse the availability and reliability evaluation of practical Ethernet Cisco device topologies. With a typical transmission substation in mind, dependability block diagrams for intra-bay and inter-bay communications have been created. Additionally, the dependability and accessibility of the actual Ethernet topologies have been compared, and some recommendations have been derived from the findings. These recommendations include the following Index Terms: substation automation systems (SAS), availability, IEC 61850, smart electronic device (IED), and dependability.

The 4D Camera: An 87 kHz Direct Electron Detector for Scanning/Transmission Electron Microscopy.

We describe the development, operation, and application of the 4D Camera-a 576 by 576 pixel active pixel sensor for scanning/transmission electron microscopy which operates at 87,000 Hz. The detector generates data at ∼480 Gbit/s which is captured by dedicated receiver computers with a parallelized software infrastructure that has been implemented to process the resulting 10-700 Gigabyte-sized raw datasets. The back illuminated detector provides the ability to detect single electron events at accelerating voltages from 30 to 300 kV. Through electron counting, the resulting sparse data sets are reduced in size by 10--300× compared to the raw data, and open-source sparsity-based processing algorithms offer rapid data analysis. The high frame rate allows for large and complex scanning diffraction experiments to be accomplished with typical scanning transmission electron microscopy scanning parameters.

Влияние цифровых технологий на бытие и становление новых форм коммуникации (селфи)

The research aims to determine the impact of digital technologies on the development of new forms of communication (including selfies) that respond to the needs of the modern individual. The article provides a theoretical reflection on the features of the development of information and communication technologies and their impact on meeting the communication needs of society. The negative consequences of screen-based and virtual communication are highlighted, and it is noted that digital technologies contribute to the development of a special form of communication aimed at presenting oneself to others through the posting of one’s photographs online. The scientific novelty of the work lies in identifying the ontological-social significance of the influence of digital technologies on the communicative component of modern society from the perspective of the gadget-defining component, where the electronic device acts as an intermediary, dictating new rules of behavior and methods of communication interaction. The article examines forms of interpersonal communication and communicative behavior strategies caused by the development of digital technologies, identifies the negative consequences of screen-based and visual communication, and offers ideas for overcoming them. As a result of the study, the authors concluded that selfies, as a special way of self-presentation and conveying information about oneself to others, are an important element of communication for the modern individual. This type of communication is determined by the development of digital technologies and is available to everyone, as it is not limited by national-cultural and language barriers. Selfies are a visualized text that does not require special erudition to understand, which explains both the positive and negative sides of this phenomenon. The authors believe that selfies will not lose their relevance in the future, therefore, considering them from the perspective of an integral and inevitable communicative component of modern existence will open up new horizons in the study of man and society, and also help minimize the negative consequences of using this type of information transmission.

Efficient resource management in direct and indirect transmission in V2X communications

Autonomous driving systems consist of vehicles that are able to communicate not only with other vehicles but also with entities in their environment, forming vehicle-to-everything (V2X) communication. However, the V2X applications have intense requirements posing a significant challenge to the telecommunication infrastructure. In this work, we consider two types of transmission, i.e. direct and indirect, and we utilize analytical traffic-engineering models with a view to conduct a performance analysis of a vehicular network that enables V2X communication. We additionally propose two resource management strategies in order to decrease the request rejection probability and consequently ensure enhanced communication conditions. The results reveal that the proposed resource management strategies constitute a strong asset for improving the system’s service provisioning capability.

Photonic defect modes in cholesteric liquid crystal resonators with embedded isotropic layers

Photonic defect modes are explored as a viable alternative to standard photonic band edge modes in photonic crystal applications, especially due to their typically high Q-factors and local density of states. For example, they can be used in nonlinearity enhancement, lasing, and cavity quantum electrodynamics. However, they are strongly dependent on any structural change and need to be well-controlled to ensure the desired resonance frequency. Here, we present a study of the photonic defect modes that appear in a structure where a layer of isotropic material is embedded between two layers of cholesteric liquid crystal (CLC), using full electrodynamics numerical simulations. We present typical transmission spectra and electric field profiles of selected defect modes and then analyze the influence of geometrical and material parameters on the eigenfrequencies and Q-factors of the modes within and around the photonic bandgap, including refractive indices and thicknesses of isotropic and liquid crystal layers, and different anchoring orientations at the boundaries of the isotropic defect layer. Additionally, a connection of such defect modes to previously extensively analyzed twist defect modes is given. Eigenmodes in asymmetric resonators are also presented, where CLC layers surrounding the intermediate isotropic layer are not equally thick, enabling biasing of specific directional light emission. More generally, this work aims to contribute to the understanding and design capability in topological soft matter photonics where defect mode lasing could be realized in CLC geometries with different singular and solitonic topological defect structures.

Synaptic imbalance and increased inhibition impair motor function in SMA.

Movement is executed through the balanced action of excitatory and inhibitory neurotransmission in motor circuits of the spinal cord. Short-term perturbations in one of the two types of transmission are counteracted by homeostatic changes of the opposing type. Prolonged failure to balance excitatory and inhibitory drive results in dysfunction at the single neuron, as well as neuronal network levels. However, whether dysfunction in one or both types of neurotransmission leads to pathogenicity in neurodegenerative diseases characterized by select synaptic deficits is not known. Here, we used mouse genetics, functional assays, morphological methods, and viral-mediated approaches to uncover the pathogenic contribution of unbalanced excitation-inhibition neurotransmission in a mouse model of spinal muscular atrophy (SMA). We show that vulnerable motor circuits in the SMA spinal cord fail to respond homeostatically to the reduction of excitatory drive and instead increase inhibition. This imposes an excessive burden on motor neurons and further restricts their recruitment to activate muscle contraction. Importantly, genetic or pharmacological reduction of inhibitory synaptic drive improves neuronal function and provides behavioural benefit in SMA mice. Our findings identify the lack of excitation-inhibition homeostasis as a major maladaptive mechanism in SMA, by which the combined effects of reduced excitation and increased inhibition diminish the capacity of premotor commands to recruit motor neurons and elicit muscle contractions.

Phase sequence selection method of double-circuit transmission lines on the same tower based on a comprehensive index

Abstract The non-transposition erection of transmission lines will lead to the imbalance of electrical parameters, which will affect the protection and automatic reclosing. The best phase sequence arrangement is determined by comprehensively considering the comprehensive indexes (current imbalance, secondary current, and recovery voltage) of double transmission un-transposed lines with shared towers. PSCAD/EMTDC electromagnetic transient simulation software is applied to build a typical 750kV transmission line model for simulation analysis, and the comprehensive indexes under different phase sequence arrangements are studied. The analysis reveals that the arrangement of phase sequence exerts a significant consequence of the comprehensive index. The findings indicate that the margin and different secondary current and recovery voltage indexes, double transmission un-transposed lines with shared towers can be erected in the same direction or in different phase sequences to reduce the current imbalance.

High-ratio planetary gearbox with EC gearing for robot applications

AbstractThe drive system of robots and robot-like systems (RLS) is often designed with a combination of an e-motor and a gearbox with a high transmission ratio to optimize performance. The various types of possible robot gearboxes can be selected based on their characteristics, which strongly influence the performance of the entire robotic system. Planetary gear drives have advantages due to their high efficiency and low design complexity. Disadvantageous is the low transmission ratio per stage and the resulting large design space required with the currently predominant involute gearing. Using special tooth profile shapes, such as the eccentric cycloid (EC) gearing, enables a high transmission ratio per stage to be achieved, thus reducing the design space required. In order to evaluate the design, a description of the geometry and characteristics of the EC gearing is necessary. The application-optimized design can be made accessible on an interdisciplinary basis using a suitable description language for the product development of the complete robotic system. The paper shows the design and analysis of a planetary gearbox with a high transmission ratio for applications in robotics. The planetary gear stage is designed with the EC gearing, which offers advantages compared to the involute gearing. The performance of the selected gearing is evaluated based on various characteristics. This allows advantages to be identified compared to the established types of transmission for robots and RLS. Overall, the paper presents a new robot gearbox with a comprehensive description and analysis directly accessible for simulation or production using additive manufacturing.

HIV, HCV and HIV-HCV Coinfections in the General Population versus Inmates from Romania.

The objective of this study was to analyze the epidemiological links of the human immunodeficiency virus (HIV), hepatitis C virus (HCV) and HIV-HCV coinfections to less studied types of transmission in certain populations. We performed an observational, prospective study on 903 patients aged between 15-87 years who took part in the Open Test Project. They were divided in two subgroups: general population vs. individuals from prisons who were questioned about multiple risk factors. A chi-square independence test was used to establish correlations between risk factors and results of screening tests. Logistic regression was used to calculate the probability of a reactive screening test based on each independent risk factor and age. HIV was very strongly associated with unprotected sexual intercourse with HIV-positive partners (the strongest association), unprotected sexual intercourse with sex workers, newly diagnosed sexually transmitted diseases (STDs), intravenous drug users (IDUs) and sharing injecting materials. In the case of HCV reactive tests, very strong associations have been established with IDUs (the strongest association), unprotected sex with IDUs and sharing injecting materials. Our study indicates the need for implementing targeted public health programs, tailored to the local epidemiology that can ultimately lead to micro-elimination of hepatitis and HIV infections in this area.

Preparation and research of high electromagnetic wave transmission type concrete in 5G frequency band

In urban areas with many buildings, the transmission of 5 G signals can be greatly absorbed or reflected, leading to decreased effectiveness of transmission. To address the issues mentioned above, the functional admixture formed by the mixture of nanocrystalline cellulose (NCC) and diammonium hydrogen phosphate (DAP) is added into concrete in this study, the electromagnetic transmission performance (ETP) and mechanical properties of concrete are enhanced simultaneously for the first time, and the electromagnetic transmission coefficient of concrete is doubled. When NCC and DAP are mixed, the electromagnetic transmission coefficient of concrete improved by 117.65 %-124.35 %, among which, when 0.5 wt% DAP and 4 wt% NCC are mixed, the electromagnetic transmission coefficient of concrete is the highest, and some frequency bands are as high as 70 %, meeting the requirements of electromagnetic wave transmitting materials. In addition, the compressive strength of concrete containing 4 wt% NCC and 0.5 wt% DAP increases by 24.3 % compared to concrete containing only 4 wt% NCC.

Examining drivers injury severity for manual and automatic transmission vehicles-involved crashes: Random parameter mixed logit model with heterogeneity in means and variances

The effect of vehicle transmission type on driver injury severities have not been thoroughly studied. The study used four-year historical crash data that occurred between the year 2019 and 2022 in Ghana. The data shows 1856 and 2272 crashes for automatic and manual transmission, respectively. The study examined the factors influencing driver injury severity in crashes involving vehicles with manual and automatic transmissions, using Random Parameter Mixed Logit Model to account for heterogeneity in the dataset. It was observed that use of manual transmission is related to a higher risk of incapacitating and fatal injuries compared to automatic transmission. Specifically, for automatic transmission vehicle-involved crashes, factors related to fatal injury were overaged vehicles, public transport, morning and evening peak hours, head-on and rollover crashes. Crashes involving saloon cars and low age cars were associated with incapacitating injury whiles rainy weather condition was related to both fatal and incapacitant injuries. Regarding manual transmission, fatal injury was associated with crashes involving male and novice drivers, cars, pickup trucks, HGV, public transports, morning and evening peak hours, rainy weather conditions and curved roads. Also, buses, private cars and trip distance were related to incapacitating injury. The rollover crashes and overaged vehicles were also associated with both fatal and incapacitating injuries. Four random parameters demonstrated heterogeneity in means, with two factors influencing the variances of two parameters for automatic transmission model. For the manual transmission model, five random parameters showed heterogeneity in means, with four variables influencing the variances of three parameters. These findings are valuable for policymakers, manufacturers, and drivers in implementing targeted interventions and safety measures to promote road safety.

Optimal Multiple Wind Power Transmission Schemes Based on a Life Cycle Cost Analysis Model

Due to the high cost and complex challenges faced by offshore wind power transmission, economic research into offshore wind power transmission can provide a scientific basis for optimal decision-making on offshore wind power projects. Based on the analysis of the topology structure and characteristics of typical wind power transmission schemes, this paper compares the economic benefits of five different transmission schemes with a 3.6 GW sizeable onshore wind farm as the primary case. Research includes traditional high voltage alternating current (HVAC), voltage source converter high voltage direct current transmission (VSC-HVDC), a fractional frequency transmission system (FFTS), and two hybrid DC (MMC-LCC and DR-MMC) transmission scenarios. The entire life cycle cost analysis model (LCCA) is employed to thoroughly assess the cumulative impact of initial investment costs, operational expenses, and eventual scrap costs on top of the overall transmission scheme’s total cost. This comprehensive evaluation ensures a nuanced understanding of the financial implications across the project’s entire lifespan. In this example, HVAC has an economic advantage over VSC-HVDC in the transmission distance range of 78 km, and the financial range of a FFTS is 78–117 km. DR-MMC is better than the flexible DC delivery scheme in terms of transmission capacity, scalability, and offshore working platform construction costs in the DC delivery scheme. Therefore, the hybrid DC delivery scheme of offshore wind power composed of multi-type converters has excellent application prospects.

Joint diagnosis and validation of lightning risk for transmission lines by using multisource data

This study proposes an improved method for assessing lightning risk for typical 750-kV transmission lines in Northwest China. The method involves enhanced preprocessing of multisource parameters and a joint diagnosis of lightning risk; on the basis of the diagnosis results, a cause analysis is conducted to identify towers at high lightning risk. In this study, raw data on the following parameters were obtained and processed: line lightning withstand capability calculation parameters, lightning localization parameters, microtopography parameters, and distributed monitoring parameters. These data were then integrated into a comprehensive multisource database. Furthermore, this study established a model for calculating lightning withstand capability; the study considered the influence of altitude and optimized the classic electrogeometric model. The joint diagnosis method was validated using distributed monitoring data. Through this method, this study identified the characteristics of typical high-risk towers and the underlying factors contributing to the high lightning risk on transmission lines.

Transmissive and reflective type multi-nanolayer electro-optical modulators for chip-to-chip free space optical interconnection: wavelength-scale electromagnetic modelling by the method of single expression

Transmissive and reflective type multi-nanolayer electro-optical modulators for chip-to-chip free space optical interconnection: wavelength-scale electromagnetic modelling by the method of single expression