Tracking Characteristics Research Articles

Investigation on the relationships among process parameters, molten pool characteristics, and fabrication quality of Ti-10V-2Fe-3Al by laser direct energy deposition

Ti-10 V-2Fe-3Al (Ti-1023) titanium alloy is a metastable high-strength β titanium alloy. Defects such as spatters, pores, and poor surface quality tend to occur during the laser direct energy deposition (LDED) of Ti-1023 titanium alloys, prohibiting its large-scale engineering application. Therefore, to obtain high-quality LDED of Ti-1023 titanium alloy, this study used a regression analysis model to investigate the relationship between key process parameters and the geometrical characteristics of single clad tracks to obtain the forming process map. In addition, an off-axis high-speed camera was used to monitor the forming process of the Ti-1023 titanium alloy single clad tracks, and the correlation between the forming quality of the three types of forming conditions—namely incomplete melting, normal melting, and over-melting—and the characteristics of the molten pool was analyzed. Finally, this study established a simplified relationship between the process parameters, the molten pool characteristics, and fabrication quality of LDED of Ti-1023 titanium alloy, which is expected to improve development for the online monitoring and increase the application of LDED Ti-1023 titanium alloy.

The Role of In-Service Pavement Studies on the German Highway Network in the Innovation Process

Innovations in the road construction sector are key to tackling the major challenges that the transport infrastructure sector is currently facing. In-service pavement studies (ISPS) are a vital component of the innovation process in the highway infrastructure sector. This paper defines the role of ISPS in the innovation process of the German highway construction sector and identifies suitable criteria to assess and evaluate the innovation characteristics of the in-service test tracks. In conclusion it provides generalisable recommendations how ISPSs can be improved as a tool to foster further innovations in the sector. To gain insights into the innovation characteristics of the ISPS qualitative expert interviews were conducted with the researchers that were responsible in setting-up, monitoring and evaluating the ISPSs.

Psychological characteristics of athletes-track and field athletes with DMCS depending on their sports qualifications

The purpose of the research is related to the study of the psychological characteristics of track and field athletes of different levels of athletic qualifications who have musculoskeletal system damage. In total, 22 athletes participated in the study. The first group included Paralympic athletes of the highest skill level (members of the national teams of Russia, Masters of Sport, World Class Sport Masters), the second group included athletes of lower grades (the first grade, Candidates for the Master of Sports). The research methods: the method of "Locus of control" by J. Rotter, Salvatore Maddi's resilience test adaptation in the version of D. Leontiev, a technique for diagnosing stress (K. Schreiner), K. Lusin's emotional intelligence test. The results of the study revealed significant differences in locus control depending on the level of sports qualification (p≤0.01). The athletes with higher grades have more noticeable internality, and most of all in terms of individual achievements. For athletes of lower grades, the external locus of control is more characteristic. Reliable direct correlations of the internal locus of control with indicators of resilience, such as engagement and control have been revealed. A negative relationship between the external locus of control and the resilience of track and field athletes with musculoskeletal system damage has also been revealed. The revealed facts allow to build the right psychological work with athletes, aimed both at improving the psychological training of athletes and at organizing the educational and training process.

Features of the temperament of track and field athletics depending on their sports specialization

The purpose of the study was to study the individual typological characteristics of track and field athletes, depending on the specialization and level of sports qualifications. The study involved 30 athletes, a total of 30 elite athletes participated in the study; the average age of the respondents was 23.5 years, among them 21 athletes have had the titles of Honored Master of Sports, Master of Sports of International Degree, Master of Sport. To assess the individual typological characteristics of athletes, the method of G. Aizenk was used. The results of the study showed that there are significant differences in the individual typological characteristics of track and field athletes in different types of specializations. It was revealed that among the athletes of speed and power athletics (short sprint, long jump, triple jump, high jump and pole vault), athletes of predominantly sanguine and choleric-melancholic temperament types predominate. Among the athletes of the speed–strength endurance group (400 m runners), there are athletes with a bright predominance of a mixed type of sanguine-choleric. In the group of athletes with a specialization in endurance (middle- and long-distance runners), athletes of a sanguine-phlegmatic type of temperament predominate in 75% of cases. The conducted research with the participation of successful and highly qualified athletes makes it possible to identify those individual typological features of athletes that can be considered as models during selecting athletes for various types of specializations.

Maximum Power Extraction Control Algorithm for Hybrid Renewable Energy System

In this research, a modified fractional order proportional integral derivate (FOPID) control method is proposed for the photovoltaic (PV) and thermoelectric generator (TEG) combined hybrid renewable energy system. The faster tracking and steady-state output are aimed at the suggested maximum power point tracking (MPPT) control technique. The derivative order number (µ) value in the improved FOPID (also known as PIλDµ) control structure will be dynamically updated utilizing the value of change in PV array voltage output. During the transient, the value of µ is changeable; it’s one at the start and after reaching the maximum power point (MPP), allowing for strong tracking characteristics. TEG will use the freely available waste thermal energy created surrounding the PV array for additional power generation, increasing the system’s energy conversion efficiency. A high-gain DC-DC converter circuit is included in the system to maintain a high amplitude DC input voltage to the inverter circuit. The proposed approach’s performance was investigated using an extensive MATLAB software simulation and validated by comparing findings with the perturbation and observation (P&O) type MPPT control method. The study results demonstrate that the FOPID controller-based MPPT control outperforms the P&O method in harvesting the maximum power achievable from the PV-TEG hybrid source. There is also a better control action and a faster response.

European heatwave tracks: using causal discovery to detect recurring pathways in a single-regional climate model large ensemble

Summer heatwaves repeatedly affect extended regions in Europe, resulting in adverse economic, social, and ecological impacts. Recent events, e.g. the 2022 heatwave, also attract interest regarding the spatial shifts of their impact centers. Evaluations so far either investigated heatwave passages at pre-defined locations or employed algorithms to spatio-temporally track their core regions. Usually, the latter focus on single events, and thus often fail to generalize spatial heatwave tracks or ignore track characteristics. Here, we use a data-driven approach employing causal discovery to robustly characterize European heatwave tracks in single-model initial condition large ensemble (SMILE) climate simulations to overcome sampling uncertainties of observational records. This enables us to identify specific recurrent heatwave tracks, evaluate their preferential seasonal occurrence, and associate them with moving high pressure centers. Additionally, the evaluation of heatwave track representation in the SMILE extends standard model evaluation, which is mostly based on static statistics. We provide the first comprehensive analysis on heatwave tracks considering internal climate variability conducted within a SMILE, promoting the latter as a methodological testbed in climate extremes research.

Characterizing Ancient Murrelet Synthliboramphus antiquus movement behaviour during breeding‐season foraging trips using hidden Markov models

Seabird species are increasingly threatened globally due to a range of anthropogenic impacts affecting at‐sea habitat. Characterizing at‐sea movement patterns and identifying foraging behaviour allows researchers to identify critical habitat but can be challenging for small diving species. The Ancient Murrelet Synthliboramphus antiquus is an alcid species of conservation concern in Canada. At‐sea distribution and movements of this species during the breeding season are currently poorly understood. We mounted GPS tracking devices on breeding Ancient Murrelets from two colonies along the southeastern coast of Haida Gwaii, one colony in 2018 and one in 2019, to collect movement data during foraging trips. We used hidden Markov models (HMMs) to identify three movement behaviour states from track characteristics, which we interpreted as transit, resting and foraging. Immersion data collected from the GPS tags allowed us to interpret the two slow‐moving states and to confidently identify foraging movement behaviour. From the 42 individuals tracked we found that foraging trips encompassed large areas of Hecate Strait, to the east of the colonies. Birds nesting on Ramsay Island in 2018 travelled on average 453 km in 4.3 days, up to a mean of 108 km from the colony. Birds breeding on George Island in 2019 took shorter trips, travelling on average 263 km in 3.0 days, and up to 81 km from the colony. In both years, birds spent approximately one‐third of their time in each behaviour state. Resting often took place throughout a whole night at sea; foraging occurred predominately during the day. Transit took place during the night, when birds were leaving or returning to the colony, or during the day, possibly indicating movement between prey patches. Our results can inform marine conservation of this vulnerable species by differentiating foraging from other at‐sea movement behaviours and is a first step to identifying critical foraging habitat.

High sensitivity tactile sensors with ultrabroad linear range based on gradient hybrid structure for gesture recognition and precise grasping

Tactile sensors simultaneously with high sensitivity and ultrabroad linear range are crucial for skin-like dexterous manipulation of robots and prosthetics, which is not realized in previous research. Therefore, achieving linearity and high sensitivity simultaneously over a wide pressure range remains a major challenge. To solve this issue, a gradient pore/pyramid hybrid structured (GPPHS) conductive composite film is designed and fabricated with gradient compression characteristic and high structural compression properties, which show improved the sensitivity and extended the linear range. The GPPHS based tactile sensor reveals a high sensitivity of 40.12 kPa−1 over an ultrawide linearity range up to 1000 kPa, which is first largest linear range so far reported. Further, a gesture recognition smart glove, prosthetic hand tactile sensing system and a flexible sensing array based on GPPHS based tactile sensor are developed, and demonstrate unique gesture tracking characteristics, precise grasping ability and multi-touch sensing capacity.

A new software tool for computer assisted in vivo high-content analysis of transplanted fluorescent cells in intact zebrafish larvae.

Acute myeloid leukemia and myelodysplastic syndromes are cancers of the bone marrow with poor prognosis in frail and older patients. To investigate cancer pathophysiology and therapies, confocal imaging of fluorescent cancer cells and their response to treatments in zebrafish larvae yields valuable information. While zebrafish larvae are well suited for confocal imaging, the lack of efficient processing of large datasets remains a severe bottleneck. To alleviate this problem, we present a software tool that segments cells from confocal images and track characteristics such as volume, location in the larva and fluorescent intensity on a single-cell basis. Using this software tool, we were able to characterise the responses of the cancer cell lines Molm-13 and MDS-L to established treatments. By utilizing the computer-assisted processing of confocal images as presented here, more information can be obtained while being less time-consuming and reducing the demand of manual data handling, when compared to a manual approach, thereby accelerating the pursuit of novel anti-cancer treatments. The presented software tool is available as an ImageJ java-plugin at https://zenodo.org/10.5281/zenodo.7383160 and the source code at https://github.com/Jfo004/ConfocalCellSegmentation.

Control algorithm of weight on bit and rate of penetration based on drilling robot

At present, the traction force and traction speed of the drilling robot cannot be controlled. However, if the speed of the drilling robot is too high, the bit will be damaged because of the shock load. If the speed of the drilling robot is too low, the drilling efficiency will be very low. The existing control system and control algorithm of the drilling robot cannot meet the requirements of the drilling conditions. A control system of the weight on bit and the rate of penetration of the drilling robot was invented. On the basis, a dual-loop fuzzy proportional integral derivative (PID) control algorithm of the pressure difference and flow rate was proposed to control the weight on bit and rate of penetration. Furthermore, the simulation model of the dual-loop fuzzy PID control algorithm was established. It is found that the proposed dual-loop fuzzy PID control algorithm has the characteristics of small overshoot and good tracking. Furthermore, the correctness of the theory was verified by the experiments. The experiments show that the average amplitude of rate of penetration vibration by using adaptive PID controller is less than 50% of that of PID controller. The maximum weight on bit with the adaptive PID controller is only 45.94% of that of the conventional PID controller. The overshoot of the adaptive PID controller is only 24.07% of that of the conventional PID controller. At the same time, the vibration amplitude of the conventional PID controller is obviously larger than that of the adaptive PID controller. The proposed adaptive PID controller in this paper can effectively reduce the vibration of the bit. By reducing the vibration of the bit, the life of the bit can be extended. Finally, it is of great significance to realize the efficient and intelligent drilling process.

Study on the influence of damage characteristics of longitudinal ballastless track on the dynamic performance of train-track-bridge coupled systems

Study on the influence of damage characteristics of longitudinal ballastless track on the dynamic performance of train-track-bridge coupled systems

A Firefly Algorithm and Elite Ant System-Trained Elman Neural Network for MPPT Algorithm of PV Array

This article proposes a novel MPPT algorithm based on the firefly algorithm and elite ant system-trained Elman neural network (FA-EAS-ElmanNN). First, the position of fireflies is randomly initialized by the firefly algorithm (FA), meanwhile the firefly individuals with higher attractiveness degree value are selected as the optimal solution. Second, the extra pheromones are artificially released to boost the positive feedback effect and convergence rate of the elite ant system (EAS). Third, the weight and threshold of the Elman neural network (ElmanNN) are updated by the FA and EAS. Also, the trained ElamnNN is employed to acquire the maximum voltage of the photovoltaic (PV) array. At last, the PID controller and PWM technology are adapted to regulate the switch time of the boost converter. Furthermore, MATLAB/Simulink is adopted to acquire the datasets of irradiance, temperature, and maximum voltage and validate the reliability and superiority of the proposed algorithm under complex atmospheric conditions. The tracking characteristic, response speed, and efficiency of the proposed MPPT algorithm are contrasted with the particle swarm optimization (PSO), ant colony optimization (ACO), ACO-artificial neural network (ACO-ANN), and PSO-RBF neural network (PSO-RBNFNN) algorithm via simulation. The efficiency of the FA-EAS-ElmanNN algorithm is 99.73%, compared with the ACO-ANN, PSO-RBFNN, PSO, and ACO algorithm, which is increased by 0.49%, 0.58%, 1.2% %, and 1.5%, respectively. Additionally, the experimental setup is built to demonstrate the tracking characteristic of the proposed MPPT algorithm.

On adjustable and lossless suppression to disturbances and uncertainties for nonminimum-phase laser pointing system

This paper focuses on the nonminimum-phase laser pointing system’s disturbances and uncertainties rejection problems on moving platforms. Moving platforms cause a variety of noticeable vibrations that substantially impair pointing accuracy. Additionally, the disturbance-observer-based control approaches currently in use sacrifice the desired disturbance suppression effects, stability margins, or tracking characteristics due to the nonminimum-phase laser pointing system. This paper suggests an adjustable disturbance-observer-based control strategy with dual filters to obtain lossless and adjustable disturbance suppression effects without sacrificing stability margins or tracking characteristics. The closed-loop controller and forward plant are presented to reduce the laser pointing system’s nonminimum-phase properties. An additional flexible filter is added to deal with the weakened nonminimum-phase system. Both filters are uniformly proposed depending on various disturbances brought on by moving platforms and work together to accomplish lossless desired disturbance suppression effects. The analyses and experiments show that the suggested approach can accomplish the lossless and adjustable disturbance suppression effects in the nonminimum-phase laser pointing system, which cancels out many more disturbances and uncertainties than the current methods.

Track Line Recognition Based on Morphological Thinning Algorithm

In the field of intelligent driving of freight trains, determining the track line ahead of the train is an important function in the autopilot technology of such trains. Combining the characteristics of freight railway tracks, we conduct an in-depth analysis of the shortcomings of object detection technology in extracting track lines and propose an improved Zhang–Suen (ZS) thinning theory for a railway track line recognition algorithm. Through image preprocessing and single pixel thinning steps, a continuous track line is obtained and then processed by a denoising algorithm to obtain a complete track line. Experimental results show that the track extracted by our method has good continuity and less noise. It can simultaneously perform track detection on straight roads, curves and turnouts, and is suitable for changing weather conditions such as sunny daytime, mild rainy daytime, cloudy daytime, night with lamp lighting and night without lamp lighting conditions.

Monitoring gas flaring in Texas using time-series sentinel-2 MSI and landsat-8 OLI images

• A high-resolution inventory of gas flaring in Texas is constructed. • Spatial-temporal characteristics of gas flaring over Texas are analyzed. • The greenhouse gas emissions hotspots from the gas flaring regions are explored. Since the shale Oil/Gas revolution, gas flaring and venting in the United States has garnered increasing attention. There is a pressing need to understand the spatial–temporal characteristics of gas flaring and track the associated greenhouse gas emissions. In this context, we use a thermal anomaly index (TAI) incorporating the Google Earth Engine (GEE) cloud computation and local batch processing for monitoring gas flaring and characterizing its spatial–temporal dynamics. We then apply a quantitative analysis of satellite-based carbon dioxide (CO 2 ) and methane (CH 4 ) in the gas flaring region. Here, we generate a gas flaring sites inventory in Texas from 2013 to 2022 based on > 83,500 multi-source moderate-resolution images (including 74,627 Sentinel-2 Multispectral Instrument [MSI] images and 8,969 Landsat-8 Operational Land Imager [ OLI] images). Validations and comparisons demonstrate that our method is reliable for MSI and OLI images, with an overall accuracy of > 95 % and a low commission rate and omission rate. We detected 217,034 gas flares from 9,296 flaring sites in Texas, and the majority (>92 %) were found in the central and western regions of the Permian Basin and the Eagle Ford Shale. The number of detected gas flaring sites vastly outnumbered the existing Visible Infrared Imaging Radiometer Suite (VIIRS) fire products, with an upward trend from 2013 to 2019 and a downward trend from 2020 to 2022. Notably, the gas flaring sites dropped significantly at the beginning of the COVID-19 pandemic (from December 2019 to May 2020), with the lowest average monthly growth rate of −14.38 %, and fell to the level of mid-2017. Application of gas flaring data identifies the localized greenhouse gas (GHG) emission hotspots in Texas and demonstrates that the increased effect of CH4 released from gas flaring regions was significantly stronger than that of CO 2 . These findings can provide references for monitoring similar small industrial sources in the future, can be used as an essential supplement to low-resolution fire products, and improve our understanding of CO 2 and CH 4 emissions from gas flaring at fine spatial scales.

High-Resolution Hazard Assessment for Tropical Cyclone-Induced Wind and Precipitation: An Analytical Framework and Application

Intensified tropical cyclones (TCs) threaten the socioeconomic development of coastal cities. The coupling of strong wind and precipitation with the TC process usually amplifies the destructive effects of storms. Currently, an integrated analytical framework for TC hazard assessment at the city level that combines the joint statistical characteristics of multiple TC-induced hazards and local environmental features does not exist. In this study, we developed a novel hazard assessment framework with a high spatiotemporal resolution that includes a fine-tuned K-means algorithm for clustering TC tracks and a Copula model to depict the wind–precipitation joint probability distribution of different TC categories. High-resolution wind and precipitation data were used to conduct an empirical study in Shenzhen, a coastal megacity in Guangdong Province, China. The results show that the probabilities of TC-induced wind speed and precipitation exhibit significant spatial heterogeneity in Shenzhen, which can be explained by the characteristics of TC tracks and terrain environment factors. In general, the hazard intensity of TCs landing from the west side is higher than that from the east side, and the greatest TC intensity appears on the southeast coast of Shenzhen, implying that more disaster prevention efforts are needed. The proposed TC hazard assessment method provides a solid base for highly precise risk assessment at the city level.

Analysis of Trajectory Tracking Characteristics of a Magnetically Driven Oil-Free Scroll Compressor

The conventional scroll compressor cannot run oil-free because of wear and tear and lubrication problems during operation due to some parts, such as anti-rotation devices. The magnetic drive oil-free scroll compressor (MDOFSC) uses a contactless drive method to avoid this drawback. In order to solve the swing problem of the orbiting scroll during the operation of the MDOFSC, decentralized control and centralized control are used to study the trajectory tracking characteristics. Firstly, the structure and working principle of the MDOFSC are introduced, and the system’s magnetic circuit and differential control principle are analyzed. Then, the dynamic model of the MDOFSC under the condition of non-compressed gas is established, and the coordinate matrix decoupling method is used to analyze the relationship between the degree of freedom of the system and the measurement distance of the displacement sensor. Finally, the system is simulated and experimentally studied under centralized PID control, and the experimental comparison study between decentralized control and centralized control is conducted. The results show that centralized control dramatically improves the trajectory control ability of the system.

The applicability of scarcity, originality, and transaction tracking characteristics of the dermatological industry and non-fungible token.

The K-beauty industry has entered the global market and encompasses the global economy. In the future, it is necessary to recognize the need for rapid recognition and application of digital technologies such as non-fungible token (NFT) in a continuously changing and shared society. This literature review presents various examples of ways to increase the value of beauty brands according to the latest digital trends. The potential value of blockchain technology was reviewed while understanding the current usage status of NFT. As of July 2022, NFT's brand application cases can be confirmed, and comparisons and cases can be applied to how much it can contribute to the rise in the value of beauty brands in the future. The 41 references were finally selected using PRISMA flow diagram. In a rapidly changing time, the beauty industry pays attention to the NFT market that can develop economically. Therefore, the parts that various industries are preemptively trying were prepared by confirming the cases. The beauty industry should pay attention to the NFT market, which is an issue, and by creating a brand with scarcity value, it can apply economic activities in the beauty industry to the trend by releasing products that both consumers and sellers can satisfy.

Nontarget Suppression in Ball Sports Multitarget-Tracking Task

In order to solve the problem of large interference caused by nontarget tasks on the ball sports field, the author proposes a method for multitarget-tracking tasks. By changing the movement speed of the athletes in the expert group, the novice group, and the control group, we investigate the performance of visual attention tracking and neural oscillatory characteristics in ice hockey players. Experimental results show that the main effect of speed was significant (F = 120.58,P<0.01,ηP2 = 0.81), and post hoc comparison results showed that the faster the movement speed, the lower the tracking accuracy. The main effect of speed was significant (F = 31.96,P<0.01,ηP2 = 0.53). Post hoc comparison results showed that the faster the movement speed, the lower the ERSP value of the high-frequency alpha rhythm. It proves the influence of speed on the inhibitory effect of nontarget tasks, which is beneficial for athletes to suppress more interference information brought by opponents or the court in the game and plays an important role in improving sports performance and developing the scientific level of sports.

초등학교 읽기부진학생들의 읽기능력에 따른 잠재집단별 시선처리 특성 분석

This study analyzes the eye tracking characteristics associated with the reading ability of elementary school students with learning difficulties by using the LPA(latent profile analysis). A total of 32 elementary school students in S city were classified based on the results of the reading test. Eye tracking characteristics of each latent group were compared and analyzed by measuring the movement of the gaze in the reading fluency and silent word reading test. As a result, LPA identified five subgroups with patterns of strengths and weakness in the reading tests. There was a significant difference in the reading test scores for each latent group. Regarding the eye tracking variables for the latent groups, there was a statistically significant difference between the groups in both the total fixation time and regression in the reading fluency test. In addition, it was confirmed that the number of fixed gazes, the number of regressions, and the number of saccades were significant variables in the classification of the latent group. Based on these results, Implications of these results and suggestions for follow-up studies were discussed.