Ground Position Research Articles

Long term variation of sardine Sardina pilchardus spawning along the Atlantic coast of northwest Africa (21–26°N): characterization and spatiotemporal variability in spawning habitat

Small pelagic fish such as sardine show strong recruitment variability often associated with environmental changes influencing the spawning process and ultimately, affecting population dynamics. Sardine (Sardina pilchardus, Walbaum 1792) is one of the most exploited pelagic species along the northwest African coast. The main spawning occurs during the cold season (autumn–winter). A time-series autumn–winter surveys extending from 1994 to 2015 sampled sardine eggs, along the southern area of the Moroccan Atlantic coast (26°N–21°N) were analyzed. The present work focuses on examining the inter-annual variability of the spawning habitat by analyzing the spatial-temporal variability of sardine egg distribution and density extracted from the data collected over the period 1994–2015. Generalized additive models (GAM) were used to detect the relationships between the sardine distribution, expressed as egg density and the presence or absence data and relevant hydrobiological environmental variables, such as salinity, temperature and zooplankton biomass. The generalized additive models showed significant relationships between the environment variables (SST, SSS and Zooplankton biomass) and sardine density, but not with sardine presence. Given that the study area is characterized by high mesoscale features and significant upwelling activities, the variability of upwelling processes could explain the changes of spawning ground position and thermal window.

An Estimate of the Sensitivity of Muon Radiography Detectors to Voids in the Ground

Model simulations of test experiments on muon radiography for several configurations of voids in the ground and different muon detector positions are presented. The sensitivity of the method for the considered cases is estimated. This study lays the basis for quantitative analysis of data in muon radiography and can be used for planning future experiments.

Excitonic and electronic transitions in Me-Sb2Se3 structures.

The optical anisotropy of the Sb2Se3 crystals was investigated at 300 and 11 K. Excitonic features of four excitons (A, B, C, and D) were observed in the optical spectra of the Sb2Se3 single crystals and in the photoelectric spectra of the Me–Sb2Se3 structures. The exciton parameters, such as the ground (n = 1) and excited (n = 2) state positions and the binding energy (Ry), were determined. The effective mass of the electrons at the bottom of the conduction band (mc* = 0.67m0) as well as the holes at the four top valence bands (mv1* = 3.32m0, mv2* = 3.83m0, mv3* = 3.23m0 and mv4* = 3.23m0) were calculated in the Г-point of the Brillouin zone. The magnitude of the valence band splitting V1–V2 due to the spin–orbit interaction (Δso = 35 meV) and the crystal field (Δcf = 13 meV) were estimated in the Brillouin zone center. The energy splitting between the bands V3–V4 was 191 meV. The identified features were discussed based on both the theoretically calculated energy band structure and the excitonic band symmetry in the Brillouin zone (k = 0) for crystals with an orthorhombic symmetry (Рnma). The photoelectric properties of the Me–Sb2S3 structures were investigated in the spectral range 1–1.8 eV under E||c and E⟂c polarization conditions and at different applied voltages.

Control of electron and ion density profiles via virtual ground position control in an inductively coupled plasma

The effects of capacitive coupling on electron and ion density profiles are studied in an argon inductively coupled plasma. Electron energy probability functions and two-dimensional ion density profiles were measured by changing the termination capacitance from 200 to 1000 pF. Experimental results show that a termination capacitor creates a virtual ground on a coil, and the virtual ground suppresses the local capacitive coupling. At 2 mTorr (non-local electron kinetics), there is little change in the azimuthal electron density distribution for different termination capacitances. However, at 50 mTorr (local electron kinetics), the virtual ground causes each mode (E-mode and H-mode) to have the maximum and minimum points in the azimuthal electron density distribution. As the termination capacitance increases, the virtual ground moves along the coil and the maximum and minimum points of the electron density also move with the virtual ground. These effects are explained by electron dynamics and the power transfer mechanism in each mode (E-mode and H-mode).

Fluorescence‐based detection of field targets using an autonomous unmanned aerial vehicle system

Abstract Here we describe a proof‐of‐concept autonomous unmanned aerial vehicle (UAV) system that utilizes the fluorescence characteristics unique to different materials to scan and acquire targets in the field that includes fossils, rocks and minerals, organisms and archaeological artefacts. This is possible because these targets are often highly fluorescent against lower fluorescence backgrounds and may exhibit different colours. To detect these targets from a moving UAV, we utilize laser‐stimulated fluorescence. This involves an intense laser beam that—unlike regular UV light—can project greater distances and generate sufficient fluorescence for targets to be detected on the UAV camera many metres above the ground. The system involves a lightweight UAV programmed to fly a waypoint pattern autonomously at night over the area of interest. LIDAR maintains its height above the terrain. A near‐UV laser is projected across the ground as a horizontal line directly below the UAV. Co‐mounted with the laser is a small highly sensitive video camera stabilized on a motion‐controlled gimbal that records the laser line during the flight. An intermittent, powerful white light strobe flashes during the flight to record the UAV's ground position in the scanned area. The UAV returns with the laser video at the end of each autonomous mission. This video is post‐processed, extracting the laser line data into a long continuous scan image showing the fluorescing ground targets. Initial analysis determines what colour the targets fluoresce so that a specific colour range can be extracted from the image to identify the locations of the detected targets. The white light strobe images are then used to quickly follow‐up on the detections. This system holds the promise of becoming the lowest ‘ground truth’ layer in the mix of high‐altitude map data produced by satellite‐ and airplane‐based Geographic Information Systems. With centimetre resolution and the geochemical differences shown via fluorescence, this system will increase the scale and efficiency of data collection involving fossils, rocks and minerals including mineable materials, fluorescent organisms including biogenic mineral producers like shellfish as well as archaeological artefacts. Thus, the fields of evolution, ecology, Earth and planetary science, archaeology and other subjects involving fluorescent targets would all benefit from this new system.

ANALYSIS OF COMPETITIVE ACTIVITY HIGH RANKED FIGHTERS OF MIXED MARTIAL ARTS

Mixed martial arts - a sport, which is a combination of many techniques, schools and direction of combat sports. Nowadays, mixed martial arts are the most popular and spectacular sport of all combat sports. Analysis of competitions performances is an important aspect of training athletes. The quantitative characteristics of competitive activity make it possible to model the training process at different stages of fighters. Aim of the research – to analyze the quantitative characteristics of competitive activity of high ranked fighters. All matches of Mixed martial arts Russian Cup in 2018 were analyzed: 84 preliminary and 8 final fights (for 1 place) in all weight categories. The following quantitative characteristics of the competitive activities of high ranked fighters were analyzed in the study: average fight time; average fight time in the standing and ground positions; distribution of fights by types of victory; activity, defense and reliability performing takedowns for each weight category. Also, a comparative analysis was carried out with the competitive activity characteristics of the top athletes from the Ultimate Fighting Championship rating for each weight group. These data can be used as model when planning the training process of both young and qualified athletes.

Evacuation Guidance Design: An Experimental Study Based on Eye Tracking Devices

It is a crucial issue whether evacuees follow the evacuation guidance during evacuation. Good evacuation guidance is necessary to be designed to help the evacuees follow the guidance. In this paper, evacuation experiments based on wearable eye tracking devices were carried out to study the design effect of the evacuation guidance. Three factors were considered in these experiments: 1) the position of the evacuation guidance; 2) follow guidance or follow other evacuees; 3) follow a stranger or a familiar person. The results show that more participants noticed the guidance with low position and ground position than the guidance with up position. The evacuees intend to follow others rather than to follow the guidance, i.e. most evacuees act as “follower”. Eye tracking evacuation experiments can also be used to test the effectiveness of evacuation guidance signs.

A Novel UAV-Assisted Positioning System for GNSS-Denied Environments

Global Navigation Satellite Systems (GNSS) are extensively used for location-based services, civil and military applications, precise time reference, atmosphere sensing, and other applications. In surveying and mapping applications, GNSS provides precise three-dimensional positioning all over the globe, day and night, under almost any weather conditions. The visibility of the ground receiver to GNSS satellites constitutes the main driver of accuracy for GNSS positioning. When this visibility is obstructed by buildings, high vegetation, or steep slopes, the accuracy is degraded and alternative techniques have to be assumed. In this study, a novel concept of using an unmanned aerial system (UAS) as an intermediate means for improving the accuracy of ground positioning in GNSS-denied environments is presented. The higher elevation of the UAS provides a clear-sky visibility line towards the GNSS satellites, thus its accuracy is significantly enhanced with respect to the ground GNSS receiver. Thus, the main endeavor is to transfer the order of accuracy of the GNSS on-board the UAS to the ground. The general architecture of the proposed system includes hardware and software components (i.e., camera, gimbal, range finder) for the automation of the procedure. The integration of the coordinate systems for each payload setting is described, while an error budget analysis is carried out to evaluate and identify the system’s critical elements along with the potential of the proposed method.

The Role of Improved Ground Positioning and Forest Structural Complexity When Performing Forest Inventory Using Airborne Laser Scanning

The level of spatial co-registration between airborne laser scanning (ALS) and ground data can determine the goodness of the statistical inference used in forest inventories. The importance of positioning methods in the field can increase, depending on the structural complexity of forests. An area-based approach was followed to conduct forest inventory over seven National Forest Inventory (NFI) forest strata in Spain. The benefit of improving the co-registration goodness was assessed through model transferability using low- and high-accuracy positioning methods. Through the inoptimality losses approach, we evaluated the value of good co-registered data, while assessing the influence of forest structural complexity. When using good co-registered data in the 4th NFI, the mean tree height (HTmean), stand basal area (G) and growing stock volume (V) models were 2.6%, 10.6% and 14.7% (in terms of root mean squared error, RMSE %), lower than when using the coordinates from the 3rd NFI. Transferring models built under poor co-registration conditions using more precise data improved the models, on average, 0.3%, 6.0% and 8.8%, while the worsening effect of using low-accuracy data with models built in optimal conditions reached 4.0%, 16.1% and 16.2%. The value of enhanced data co-registration varied between forests. The usability of current NFI data under modern forest inventory approaches can be restricted when combining with ALS data. As this research showed, investing in improving co-registration goodness over a set of samples in NFI projects enhanced model performance, depending on the type of forest and on the assessed forest attributes.

Experimental study of <SUP align=right>41</SUP>Ar activity release rate from the Bangladesh Atomic Energy Commission TRIGA research reactor

The present study focused on the monthly or annual 41Ar activity release rate and ground level activity concentration measurement including the estimation of public dose level at the ground and stack positions of the Bangladesh Atomic Energy Commission TRIGA Research. During the experimental work, a Geiger-Muller (G-M) counter was used for the air sample count rate study. The experimental results demonstrated that the obtained maximum monthly or annual 41Ar activity release rate (2.48 × 1010 Bq/month or 6.25 × 1011 Bq/year) and monthly maximum ground level 41Ar activity concentration (6.40 × 101 Bq/m3) were within the permissible limits set by the regulatory body. This report also confirmed that the estimated public dose levels (0.29 mSv/yr and 0.0002 mSv/yr) at the stack and ground positions were far below the IAEA acceptable limit (1.0 mSv/yr) which was significant for the research reactor safety.

Experimental study of <SUP align=right>41</SUP>Ar activity release rate from the Bangladesh Atomic Energy Commission TRIGA research reactor

The present study focused on the monthly or annual 41Ar activity release rate and ground level activity concentration measurement including the estimation of public dose level at the ground and stack positions of the Bangladesh Atomic Energy Commission TRIGA Research. During the experimental work, a Geiger-Muller (G-M) counter was used for the air sample count rate study. The experimental results demonstrated that the obtained maximum monthly or annual 41Ar activity release rate (2.48 × 1010 Bq/month or 6.25 × 1011 Bq/year) and monthly maximum ground level 41Ar activity concentration (6.40 × 101 Bq/m3) were within the permissible limits set by the regulatory body. This report also confirmed that the estimated public dose levels (0.29 mSv/yr and 0.0002 mSv/yr) at the stack and ground positions were far below the IAEA acceptable limit (1.0 mSv/yr) which was significant for the research reactor safety.

Compact wideband-printed antenna for sub-6 GHz fifth-generation applications

Abstract The design of a compact wideband partial slotted ground rectangular-printed antenna is presented. The design approach utilizing the slotted partial ground plane is much more flexible for improving the antenna performance. A detailed design guideline to estimate the antenna dimensions is given, which is based on mathematical and parametric analysis. The effects of variation of length of the ground and slot position in the ground plane are investigated. The simulation has been performed by using HFSS V20 simulator. The designed antenna is meant for being operated in the C band of super-high-frequency (SHF) spectrum and in the n77 band (3.3-4.2 GHz) and n78 band (3.3-3.8 GHz) of frequency range 1 (FR1) in sub-6 GHz 5G-frequency bands. The designed antenna is showing a wide bandwidth (700 MHz) with a low-reflection coefficient of −31.15 dB. The wide bandwidth and compact size of the antenna makes it suitable for use in sub-6 GHz 5G compact wireless communication systems. The measured results of the antenna prototype are firmly authenticated with simulation estimations.

Design and Analysis of UAV-Assisted Relaying With Simultaneous Wireless Information and Power Transfer

We consider a two-phase decode-and-forward (DF) relay network assisted by an unmanned aerial vehicle (UAV), where the UAV performs energy harvesting and information decoding simultaneously with a power splitting (PS) receiver structure. For the network, we optimize the PS and time allocation (TA) factors to minimize the outage probability in transferring the data from a source to a destination suffering from blockages in the direct link. The optimal solution is found in two steps, optimization of the PS factor for given TA and then optimization of the TA factor using the conditionally optimized PS factor given in a closed-form. To reduce the complexity of the optimal method, we next propose a suboptimal method using a fixed TA determined by the transmission rate only and a fixed PS ffactor given by a function of the average power of the UAV-to-destination channel. The outage probability of the proposed method is analyzed in a generalized UAV channel model including path-loss, shadowing, and Nakagami-m fading, which is shown to agree with the simulation results and is close to the optimal performance. In addition, the optimal UAV position is investigated in various channel environments, which reveals that the optimal altitude depends on the deployment scenarios and the optimal ground position is the center-point between the source and destination in general.

위성영상 지상위치관측 시스템의 정확도 분석

대한민국 국가 우주개발 중장기 계획에 따라 1992년 우리별 1호(KITSAT)를 시작으로 현재 아리랑 위성 3A호(KOMSAT-3A)까지 다목적 지구관측위성을 운용하고 있다. 인공위성 기술의 발전으로 고해상도 위성영상을 쉽게 구할 수 있게 되었으며, 이런 위성영상의 정확한 처리를 위해서는 지상기준점의 정밀한 측량과 위성영상에서 측량한 지상기준점의 정확한 사진좌표를 취득하는 것이 매우 중요하다. 본 연구는 고해상도 위성영상에서 지상위치를 자동으로 추출하는 지상위치관측 시스템을 통하여 자동으로 취득한 지상위치와 사람이 직접 측정한 지상위치 사이의 오차를 분석하여, 지상위치관측 시스템의 정확도를 분석한 결과 RMSE ±0.8m이내의 매우 높은 정확도를 얻을 수 있었으며, 앞으로 본 연구를 통해 고해상도 위성영상의 지상기준점을 자동으로 취득하여 고정밀도의 정사영상 생성, 자동 정밀지도제작 등 다양한 분야에 적용이 가능할 것이다.

PLC Based Tower Type Elevator Model for Automatic Car Parking System

Manufacturers from several industries are gaining the advantage in auto machine technology in terms of productivity, flexibility, safety, accuracy and in reducing of manual efforts etc. Operating processes are designed in different modes of operation like manual, semi-automation and automation. Semi-automation and automation processes are controlled by different control devices like micro controller, PLC etc. Currently PLC is being used for many applications like industrial automation, traffic light automation, car parking automation, home application and many areas. This study presents the application of PLC (Programmable Logic Controller) in car parking automation. The aim of this paper is to make more advantageous method of car parking by using PLC application since the car parking is main problem in shopping malls, public traffic and scarcity of land in urban areas. Different types of car parking are currently available. A step beyond the existing scenarios is tower type parking. Car parking is proposed with three floors each floor can accommodate three cars the main components are PLC, sensors and elevator, BLDC motor and programming language is ladder diagram, software is TIA portal. Car is placed on the parking area sense by sensors and select the parkingin button it parks automatically in the vacant position and light the respected slot in the panel board followed by receiving a token number. For park out select the parkingout button and slot number the car automatically reaches to ground position.

A systematic review of the nesting and overwintering habitat of bumble bees globally

Some bumble bee species are in decline globally. Declines have been attributed to many factors including habitat loss. Habitat is an integral component of any species and should be a central focus of conservation efforts to protect at risk species. However, the habitat of bumble bee species is not fully understood. We conducted a systematic review of the peer-reviewed literature using Web of Science to summarize articles that have described the habitat of bumble bee species. In total, 55 nesting and 10 overwintering habitat studies are described in this review. We described common patterns associated with bumble bee studies including overwintering habitat, landscape type, and ground position. We found that bumble bee nests are more frequently found underground and that studies were biased towards the United Kingdom and agricultural habitats. There are some preferences in nesting and overwintering habitat, but further research is needed to draw any substantial conclusions. Detection of nesting and overwintering site studies may be improved using citizen science initiatives and possibly through employing detection dogs or radio-telemetry. Increasing the detection of nesting and overwintering sites is an important priority to improve our understanding of bumble bee habitat. It is critical that we identify all aspects of bumble bee habitat to ensure the protection, restoration and creation of important resources to ensure their conservation.

Metode Pengenalan Tempat Secara Visual Berbasis Fitur CNN untuk Navigasi Robot di Dalam Gedung

Place recognition algorithm based-on visual sensor is crucial to be developed especially for an application of indoor robot navigation in which a Ground Positioning System (GPS) is not reliable to be utilized. This research compares the approach of place recognition of using learned-features from a model of Convolutional Neural Network (CNN) against conventional methods, such as Bag of Words (BoW) with SIFT features and Histogram of Oriented Uniform Patterns (HOUP) with its Local Binary Patterns (LBP). This research finding shows that the performance of our approach of using learned-features with transfer learning method from pre-trained CNN AlexNet is better than the conventional methods based-on handcrafted-features such as BoW and HOUP.

Language as a site of search for common ground and power positioning in Chinese-Finnish negotiation

This paper explores some language-related aspects in investment negotiation between Finnish and Chinese partners, such as language choices, the role of interpreters, and overcoming misunderstandings. These are seen as sites of both search for common ground in terms of positive politeness (affiliation) and power positioning in terms of negative politeness (autonomy) (Brown and Levinson 1987). This study is based on data obtained by interviewing individuals who work for state investment attraction agency and local governments in Finland and observation in delegation meetings. While misunderstandings occur, overcoming linguistic, contextual and cultural differences in understanding is possible. Common ground is more easily achieved when using English, however changing power relations with China render the use of the Mandarin Chinese necessary as well.

Influence of weather on the acoustical properties of a ground surface: measurements and models

The acoustic properties of a ground surface are well known to be affected strongly by soil moisture contents. Many studies have been conducted to quantify the effects through in-situ and laboratory measurements. The soil moisture is also well known to be influenced by continuous variability of meteorological elements such as rainfall, sunshine, and air temperature. Therefore, it is expected that the meteorological variability alters ground acoustic properties over time. For this study, an in-situ measurement campaign was held during July 2014 to January 2015 at a site in Niigata, Japan. An automatic weather station observed meteorological elements at 1-minute intervals. A buried soil moisture sensor measured water saturation in the ground near the station at 5-minute intervals. The acoustic absorption coefficient of the same ground position was measured once a day using an in-situ measurement technique. The observations showed that the absorption coefficient of the ground surface had variations with multiple timescales from days to months and seasons. Two-stage models of the influence of the weather on the absorption coefficient of the ground surface were derived from the data. The first stage models the short- and long-term effects of rainfall and the air temperature on the water saturation of the soil. The second stage models the effects of water saturation on the absorption coefficient of the ground. The derived models were found to explain the long-term and approximately half of the short-term variation of the acoustic absorption.

Estimation of Canopy Height Using an Airborne Ku-Band Frequency-Modulated Continuous Waveform Profiling Radar

An airborne Ku -band frequency-modulated continuous waveform (FMCW) profiling radar terms as Tomoradar provides a distance-resolved measure of microwave radiation backscattered from the canopy surface and the underlying ground. The Tomoradar waveform data are acquired in the southern Boreal Forest Zone with Scots pine, Norway spruce, and birch as major species in Finland. A weighted filtering algorithm based on statistical properties of noise is designed to process the original waveform. In addition, another algorithm of estimating canopy height for the processed waveform is developed by extracting the canopy top and ground position. A higher-precision reference data from a Velodyne VLP-16 laser scanner and a digital terrain model are introduced to validate the accuracy of extracted canopy height. According to the processed results from 127 765 copolarization measurements in 32 stripes of Tomoradar field test, the mean error of canopy height varies from −0.04 to 1.53 m, and the root-mean-square error approximates 1 m. Moreover, the estimated canopy heights highly correlate with the reference data in view of that the correlation coefficients maintain from 0.86 to 0.99 with an average value of 0.96. All these results demonstrate that Tomoradar presents an important approach in estimating the canopy height with several meters footprint and is feasible of being a validation instrument for satellite LiDAR with large footprint in the forest inventory.