Correction Vector Research Articles

Self-Corrective Sensor Fusion for Drone Positioning in Indoor Facilities

Drones may be more advantageous than fixed cameras for quality control applications in industrial facilities, since they can be redeployed dynamically and adjusted to production planning. The practical scenario that has motivated this paper, image acquisition with drones in a car manufacturing plant, requires drone positioning accuracy in the order of 5 cm. During repetitive manufacturing processes, it is assumed that quality control imaging drones will follow highly deterministic periodic paths, stop at predefined points to take images and send them to image recognition servers. Therefore, by relying on prior knowledge about production chain schedules, it is possible to optimize the positioning technologies for the drones to stay at all times within the boundaries of their flight plans, which will be composed of stopping points and the paths in between. This involves mitigating issues such as temporary blocking of line-of-sight between the drone and any existing radio beacons; sensor data noise; and the loss of visual references. We present a self-corrective solution for this purpose. It corrects visual odometer readings based on filtered and clustered Ultra-Wide Band (UWB) data, as an alternative to direct Kalman fusion. The approach combines the advantages of these technologies when at least one of them works properly at any measurement spot. It has three method components: independent Kalman filtering, data association by means of stream clustering and mutual correction of sensor readings based on the generation of cumulative correction vectors. The approach is inspired by the observation that UWB positioning works reasonably well at static spots whereas visual odometer measurements reflect straight displacements correctly but can underestimate their length. Our experimental results demonstrate the advantages of the approach in the application scenario over Kalman fusion, in terms of stopping point detection and trajectory estimation error.

Magnetic order and fluctuations in the quasi-two-dimensional planar magnet .

We use neutron scattering to investigate spin excitations in , which has a -axis incommensurate helical structure of the two-dimensional (2D) in-plane ferromagnetic (FM) ordered layers for . By comparing the wave vector and energy dependent spin excitations in helical ordered and paramagnetic , we find that Ni doping, while increasing lattice disorder in , enhances quasi-2D FM spin fluctuations. However, our band structure calculations within the combined density functional theory and dynamic mean field theory (DFT+DMFT) failed to generate a correct incommensurate wave vector for the observed helical order from nested Fermi surfaces. Since transport measurements reveal increased in-plane and -axis electrical resistivity with increasing Ni doping and associated lattice disorder, we conclude that the helical magnetic order in may arise from a quantum order-by-disorder mechanism through the itinerant electron mediated Ruderman-Kittel-Kasuya-Yosida (RKKY) interactions.

Comparative Effects of Monetary and Budgetary Policies on the Economy of Burkina Faso

The article analyzes on three-time horizons the comparative effects of monetary and budgetary policies on the economy of Burkina Faso. It uses two models: error correction model and vector autoregressive model. Taking into account the passage from West African Monetary Union to West African Economic and Monetary Union and econometric results indicating a break in 1994 (year of the devaluation of the currency: XOF), the period of study 1970-2010 is split in two: 1970-1993 and 1994 -2010. The results show, on the economy of Burkina Faso, monetary policy has been more effective than budgetary policy in these three periods. From 1970 to 1993, budgetary policy was ineffective on economic growth. On the period 1994-2010, the effects of monetary and budgetary policies have been weak and statistically insignificant. The devaluation of the XOF and the adoption of the Pact of Convergence of the WAEMU did not really contribute significantly to the country's economic growth. Keywords: budgetary policy, monetary policy, error correction model, vector autoregressive model, Burkina Faso DOI: 10.7176/DCS/10-11-05 Publication date: November 30 th 2020

Analisis Pengaruh Realisasi Belanja Pemerintah Terhadap Penerimaan Pajak di Indonesia

This study examines the effect of the realization of government spending consisting of goods expenditure, capital expenditure and employee expenditure on tax revenue in Indonesia. In this study, we use four analytical methods that consist of Granger Test, Partial Adjustment Model (PAM), Error Correction Model (ECM) and Vector Autoregression (VAR). The result shows that the realization of goods and employee expenditure are significant determinant of the tax revenue. Further examination shows that the shocks on goods and employee expenditure have a positive impacts toward tax revenue. However the shock effect are different on those variables. On the shock to goods expenditure, the tax revenue response will occur directly, in contrast to shock on employee expenditure that requires time lag. This study also find that between PAM and ECM, the ECM model is more appropriate to be used to explain the effect of government spending on tax revenue in Indonesia.

TRANSMISSÃO DA VARIAÇÃO DA TAXA DE CÂMBIO PARA OS PREÇOS DE EXPORTAÇÕES BRASILEIRAS DA CARNE BOVINA E DA CARNE DE FRANGO (1997-2019)

The objective of this work consisted of examining the relation between exchange rates in the Brazilian export prices of beef and chicken meat, relation defined as the pass-through of the exchange rate, having as reference the period from July, 1997 to March, 2019. The data were collected from the sites of Center for Advanced Studies in Applied Economics – CEPEA, the Institute of Applied Economics - IPEA, in WORLD BANK, and in the Bureau of Labor Statistics – BLS. In this sense, time series instrumentals were used, especially the Error Correction Vector Model. The results found indicated that the pass-through degree of the exchange rate for the export prices of beef occurred in a complete way, representing competitiveness. Yet, for chicken meat, the pass-through coefficient was incomplete, representing that the exchange rate depreciations do not translate themselves into significant gains in competitiveness, once that they reduce partially the export prices.

Dosimetric Impact of the Positional Imaging Frequency for Hypofractionated Prostate Radiotherapy - A Voxel-by-Voxel Analysis.

BackgroundTo investigate deviations between planned and applied treatment doses for hypofractionated prostate radiotherapy and to quantify dosimetric accuracy in dependence of the image guidance frequency.MethodsDaily diagnostic in-room CTs were carried out in 10 patients in treatment position as image guidance for hypofractionated prostate radiotherapy. Fraction doses were mapped to the planning CTs and recalculated, and applied doses were accumulated voxel-wise using deformable registration. Non-daily imaging schedules were simulated by deriving position correction vectors from individual scans and used to rigidly register the following scans until the next repositioning before dose recalculation and accumulation. Planned and applied doses were compared regarding dose-volume indices and TCP and NTCP values in dependence of the imaging and repositioning frequency.ResultsDaily image-guided repositioning was associated with only negligible deviations of analyzed dose-volume parameters and conformity/homogeneity indices for the prostate, bladder and rectum. Average CTV T did not significantly deviate from the plan values, and rectum NTCPs were highly comparable, while bladder NTCPs were reduced. For non-daily image-guided repositioning, there were significant deviations in the high-dose range from the planned values. Similarly, CTV dose conformity and homogeneity were reduced. While TCPs and rectal NTCPs did not significantly deteriorate for non-daily repositioning, bladder NTCPs appeared falsely diminished in dependence of the imaging frequency.ConclusionUsing voxel-by-voxel dose accumulation, we showed for the first time that daily image-guided repositioning resulted in only negligible dosimetric deviations for hypofractionated prostate radiotherapy. Regarding dosimetric aberrations for non-daily imaging, daily imaging is required to adequately deliver treatment.

Neutral-Point Voltage Oscillation Mitigation Scheme for Transformerless Three-Level PV Inverter in LVRT Operation With Selective Space Vector Modulation

In transformerless photovoltaic (PV) generation system, the neutral-point (NP) voltage balancing and the ground current reduction of three-level inverter are carefully regulated using a space vector modulation (SVM) scheme. Nevertheless, in low-voltage ride-through (LVRT) operation, the simultaneous reduction of NP voltage oscillation and common-mode voltage (CMV) has not been researched yet. To overcome these issues, a selective SVM (SSVM) strategy is proposed in this article. First, the NP voltage oscillation of three-level inverter in LVRT operation is analyzed in detail, which reveals that the NP voltage is affected by phase currents and duty cycles. Based on the location of output voltage and the direction of grid currents, the correct small vectors are selected under different power factor angles. Then, the small vector force (SVF) including the grid currents and duty cycle on NP voltage is proposed for the first time. According to the value of SVF, the optimal small vector having the most effective impact on NP voltage among the correct vectors and switching sequence is determined. With the proposed method, the NP voltage oscillation and CMV are reduced simultaneously in LVRT operation. Finally, the effectiveness of the proposed method is verified with experimental results.

An intelligent recognition system for insulator string defects based on dimension correction and optimized faster R-CNN

In this paper, an intelligent recognition system for insulator based on dimension correction and optimized faster region with convolutional neural network (R-CNN) is proposed. In the process of insulator pictures shooting, a laser radar is used to calculate the UAV correction vector. The position of the UAV is adjusted to ensure the consistency of the spatial dimensions of the pictures taken in different time dimensions. Based on the almost invariant spatial dimension, the faster R-CNN image recognition algorithm is optimized. When the target detection frame is generated, marked reference pictures are added to narrow the search range, improve the target detection frame generation speed, and reduce the number of pictures during training. Experiments and comparison analysis are included. They verify the optimized faster R-CNN image recognition algorithm requires less pictures and recognition time, and the recognition accuracy increased from 85.6 to 97.3%.

АНТИГРАВИТАЦИОННЫЕ СВОЙСТВА ВОДНОЙ СРЕДЫ И ИХ ИСПОЛЬЗОВАНИЕ ДЛЯ ГИДРОКОРЕКЦИИ ДВИГАТЕЛЬНЫХ НАРУШЕНИЙ У ДЕТЕЙ

The article considers the unique physical properties of the water environment and their positive impact to the psychophysical development of the child. The most important therapeutic and healing effect of water is described comprehensively – its anti-gravity effect on the musculoskeletal system of a human. The mechanism of the Archimedean (buoyant) force action is presented, the counteraction of which largely compensates the component of the compression gravityeffect. As a result, the overall load on the skeleton and muscle system of the child is reduced. It has fundamental correcting importance of the physical development of children with musculoskeletal systemdisorders. All the correction vectors of this general anti-gravity effect are analyzed in detail, which include: work with weakened children; wards with a delay in motor and/or psychomotor development; having hypotonic status of the muscles of the body and limbs; prevention and correction of posture disorders of children in all planes; height risestimulation of the child body; the effect of the uniform distribution of physical activity of the childmusculoskeletal system; an amplitude increase of the limbs and the jointsmovements; smooth stimulation of the supporting ability development of the feet and lower limbs; adequate stimulation of the walking function formation in lightened hydrostatic weightlessnessconditions. In the formulated conclusions, the presence of unique physical properties of water in the development, correction and recovery stimulationof children with disabilities is noted. Specific correction vectors are proposed, according to which it is possible successfully to use the general antigravity effect of water in physical educationof children with musculoskeletal systemdisorders. Prospects for further research of this scientific and practical direction of hydrocorrection are outlined, which consist of studying its capabilities in relation to children of preschool and primary school age with different types of musculoskeletal system disorders in etiology and pathogenesis. Key words: anti-gravity effect, water environment, swimming, hydrocorrection, children with musculoskeletal systemdisorders.

DETERMINATION OF SHARE PRICE OF AGRO ALLIED FIRMS: EVIDENCE FROM NIGERIA

Purpose: The study aims to investigate the determinant of the share price of agro-related firms listed on the Nigerian stock exchange.
 Methodology: We employed regression analysis, unit root test as well as vector correction model to determine the degree of relationship between share prices and each of return on assets (ROA), earnings per share (EPS), dividend per share (DPS).
 Findings: The study found that share price is majorly influenced by earnings per shares, while other variables lag it.
 Practical implications: Results from the study have some possible policy implications, for instance, it is recommended that policymakers should put in place conducive market environments that will stimulate earnings from investments. Investors should on the other hand pay keen attention to information within and outside the economy when making investment decisions.
 Originality/Value: This study is one of the first studies on determinants of share prices with a focus on agro-allied firms.

Surface-guided tomotherapy improves positioning and reduces treatment time: A retrospective analysis of 16835 treatment fractions.

PurposeIn this study, we have quantified the setup deviation and time gain when using fast surface scanning for daily setup/positioning with weekly megavoltage computed tomography (MVCT) and compared it to daily MVCT.MethodsA total of 16 835 treatment fractions were analyzed, treated, and positioned using our TomoTherapy HD (Accuray Inc., Madison, USA) installed with a Sentinel optical surface scanning system (C‐RAD Positioning AB, Uppsala, Sweden).Patients were positioned using in‐room lasers, surface scanning and MVCT for the first three fractions. For the remaining fractions, in‐room laser was used for setup followed by daily surface scanning with MVCT once weekly. The three‐dimensional (3D) setup correction for surface scanning was evaluated from the registration between MVCT and the planning CT. The setup correction vector for the in‐room lasers was assessed from the surface scanning and the MVCT to planning CT registration. The imaging time was evaluated as the time from imaging start to beam‐on.ResultsWe analyzed 894 TomoTherapy treatment plans from 2012 to 2018. Of all the treatment fractions performed with surface scanning, 90 % of the residual errors were within 2.3 mm for CNS (N = 284), 2.9 mm for H&N (N = 254), 8.7 mm for thorax (N = 144) and 10.9 for abdomen (N = 134) patients. The difference in residual error between surface scanning and positioning with in‐room lasers was significant (P < 0.005) for all sites. The imaging time was assessed as total imaging time per treatment plan, modality, and treatment site and found that surface scanning significantly reduced patient on‐couch time compared to MVCT for all treatment sites (P < 0.005).ConclusionsThe results indicate that daily surface scanning with weekly MVCT can be used with the current target margins for H&N, CNS, and thorax, with reduced imaging time.

Testing pollution haven and pollution halo hypotheses for Turkey: a new perspective.

In this study, we analyzed the asymmetric short- and long-run causal links between foreign direct investments and emissions in Turkey over the time period 1974–2018. Using hidden co-integration techniques, we defined and tested the asymmetric pollution haven and asymmetric pollution halo hypotheses. To evaluate the long-run asymmetric causal relationship, we estimated both the crouching error correction model and vector error correction model. We performed a stepwise regression model to estimate the crouching error correction model. The empirical results confirmed an asymmetric causal relationship between positive shocks of foreign direct investments and positive movements in emissions in the short run as well as an asymmetric causal link between negative and positive shocks of foreign direct investments and positive emissions in the long run. Furthermore, the results showed that increases in foreign direct investments led to a decrease in the rate of emission growth in both the short and long run. This finding supports the validity of the asymmetric pollution halo hypothesis in Turkey’s case. Policymakers should strengthen their environmental protection laws to protect the quality of their environments as well as implement policies that encourage the use of clean technology and tax incentives that increase foreign direct investment inflows. Graphical

An Optimized Framework for Plane-Probing Algorithms

A plane-probing algorithm computes the normal vector of a digital plane from a starting point and a predicate “Is a point \({x}\) in the digital plane?”. This predicate is used to probe the digital plane as locally as possible and decide on the fly the next points to consider. However, several existing plane-probing algorithms return the correct normal vector only for some specific starting points and an approximation otherwise, e.g., the H- and R-algorithm proposed in Lachaud et al. (J Math Imaging Vis 59(1):23–39, 2017). In this paper, we present a general framework for these plane-probing algorithms that provides a way of retrieving the correct normal vector from any starting point, while keeping their main features. There are \(O(\omega \log \omega )\) calls to the predicate in the worst-case scenario, where \(\omega \) is the thickness of the underlying digital plane, but far fewer calls are experimentally observed on average. In the context of digital surface analysis, the resulting algorithm is expected to be of great interest for normal estimation and shape reconstruction.

Build receptive pyramid for efficient color image compression artifact reduction

A traditional image pyramid is an effective way to extract multiscale features. However, for image restoration, downsampling and upsampling lose details in the original resolution and result in an over smooth result. To overcome this defect, we propose a receptive pyramid (RP) that replaces downsampling by dilated convolution to extract multiscale features on the original resolution and make a full resolution correction. We present an RP-based convolution neural network named receptive pyramid convolutional network (RPCN) for efficient color image compression artifact reduction (CAR). Specifically, we propose residual connected convolution blocks as the baseline of RPCN. RPs work in convolution blocks to extract the hierarchical multiscale features for local feature correction. Moreover, the global feature fusion and vector correction are also introduced to further exploit the hierarchical features from the baseline. Benefiting from the RP, our RPCN achieves state-of-the-art performance with a much smaller model and much faster running speed for the CAR task.

La dinámica exportadora manufacturera como restricción al crecimiento en México mediante el análisis de la productividad y la IED, 2005-2018

Esta investigación tiene como objetivo analizar la problemática del lento crecimiento económico de México durante el período 2005-2018 a partir de la evolución de la productividad laboral manufacturera y la Inversión Extranjera Directa (IED) como determinantes de la dinámica de las exportaciones de manufacturas, que a su vez constituyen una fuente de crecimiento económico para economías abiertas. Por otra parte, la validación de esta hipótesis se realiza a través de la metodología de Vectores de Corrección de Error (VEC), donde los resultados muestran que la incidencia de la IED es menor con relación a la productividad laboral manufacturera y que ambas variables están cointegradas en el largo plazo. Por lo tanto, se concluye que es importante atender el diseño de políticas sectoriales que se traduzcan en mejoras de la productividad laboral, y también modificar las estrategias de captación de inversión extranjera para así estimular conjuntamente el crecimiento económico.

Natural orbitals renormalization group approach to a Kondo singlet

A magnetic impurity embedded in a metal host is collectively screened by a cloud of conduction electrons to form a Kondo singlet below a characteristic energy scale $T_K$, the Kondo temperature, through the mechanism of the Kondo effect. We have reinvestigated the Kondo singlet by means of the newly developed natural orbitals renormalization group (NORG) method. We find that, in the framework of natural orbitals formalism, the Kondo screening mechanism becomes transparent and simple, while the intrinsic structure of Kondo singlet is clearly resolved. For a single impurity Kondo system, there exits a single active natural orbital which screens the magnetic impurity dominantly. In the perspective of entanglement, the magnetic impurity is entangled dominantly with the active natural orbital, i.e., the subsystem formed by the active natural orbital and the magnetic impurity basically disentangles from the remaining system. We have also studied the structures of the active natural orbital respectively projected into real space and momentum space. Moreover, the dynamical properties, represented by one-particle Green's functions defined at impurity site with active natural orbital, were obtained by using correction vector method. In order to clarify the spatial extension of the Kondo screening cloud, the concept of Kondo correlation energy was introduced. With this concept we obtain a characteristic length scale beyond which the Kondo screening cloud is hardly detected in experiment. Our numerical results indicate that this characteristic length scale usually is just a few nanometers, which interprets why it is difficult to detect the Kondo screening cloud experimentally in a metal host.

Power‐efficient compensation circuit for fixed‐width multipliers

A fixed-width multiplier receives two n-bit operands and generates an approximate n-bit product as the output. It truncates part of the partial products and employs an appropriate error compensation circuit in order to reduce the approximation error. In this study, a new error compensation circuit for the fixed-width multiplier has been proposed which utilises the correction vector (CV) and modified minor CV. The proposed error compensation circuit is capable of minimising both the mean error and the mean-square error. Post-synthesis results for 16-bit of fixed-width multiplier demonstrate that the proposed circuit has 3.50, 39.24, 42.91 and 44.91% reduced delay, area, power consumption and power–delay product when compared with the existing design reported in the literature.

THE RECIPROCITY PRINCIPLE FOR A NONLINEAR ANISOTROPIC MEDIUM WITHOUT HYSTERESIS: THEORY AND PRACTICE OF APPLICATION

The construction of the correct vector material equations for nonlinear anisotropic soft magnetic materials remains one of the main reserves for increasing the accuracy of mathematical models in solving magnetostatic problems in the field formulation. The aim of the work is to establish asymptotic expressions for the reciprocity principle, which is a fundamental property of reversible magnetization processes of nonlinear anisotropic media, and to use the obtained results to optimize the computational process when constructing the vector magnetization characteristic and differential permeability tensor. The potentiality property of the magnetic flux density vector B in H -space is used. The main result of the paper is an illustration, using concrete examples, of an alternative method for calculating vector magnetization characteristics for one of the orthogonal families. In order to eliminate the instrumental error and ensure maximum accuracy and reliability of the obtained results, the exact characteristics for the components of the vector magnetization characteristic obtained by differentiating a special analytical expression for the potential were used as initial ones. The principle of reciprocity, by virtue of its universal nature, makes a significant contribution to the theory of nonlinear anisotropic media in the hysteresis-free approximation. Asymptotic expressions for the reciprocity principle are obtained for the first time. The performed computational experiments on the construction of vector characteristics based on the known magnetization characteristics in one of the directions confirm almost complete coincidence with the exact values obtained analytically. The use of asymptotic expressions for the reciprocity principle not only greatly simplifies computational processes for determining the orthogonal magnetization characteristics, but also implements the calculation of differential permeability tensors for arbitrary field values. The proposed method can be implemented in applications for calculating the magnetic field in devices with nonlinear anisotropic magnetically soft materials, primarily with cold rolled sheet electrical steels, which are most used in electrical engineering.

Development and Degradation: The Nexus between GDP, FDI, and Pollution in India

The nexus between development and environment has been a debatable topic for years, more so when foreign direct investment (FDI is used to accelerate the economy. Since environmental Kuznets curve may not be achievable by all economies and many studies have not been able to establish a consistent relationship between FDI and environment, this study determines the liaison between FDI, GDP, and pollution in India with time series data from 1990 to 2015. While per capita GDP plotted against per capita carbon dioxide (CO2) emission indicates an alarming positive relation, the co-integration between FDI, GDP, and CO2 tested using unit root test statistics (augmented Dickey–Fuller test) for stationarity and then by Johansen and Juselius’s multivariate co-integration technique show a long-run co-integration. Since the existence of a relationship between variables does not prove causality, the variables are phrased in a vector error correction (VEC) form and vector error correction mechanism (VECM) Granger causality/block exogeneity Wald test which reveals that FDI has a positive and significant impact on pollution and GDP attracts FDI. This transitive relation suggests that FDI in pollution-controlling technology would be a feasible solution to sustainable development.

APPLICATION OF THE SLIDING WINDOW MECHANISM IN SIMULATION OF COMPUTER NETWORK LOADING PARAMETERS

The subject of the study in the article is the data transfer processes in computer networks from the point of view of the network performance indicators, in particular, overload parameters. The purpose of the work is to create a simulation model of the behavior of a computer network, taking into account the mechanism of the sliding window and to demonstrate its work using a test example in combination with the previously proposed algorithms. The following tasks are solved in the article: analysis of the network as a complex multilevel system and isolation of the problems related to the transport layer of the OSI model; consideration of tasks that are solved by the transport layer of the data network; creation of the mechanism of modeling of functions of sliding window; demonstration of model work. The following research methods are used: basics of system analysis, models of network functioning, simulation modeling method. The following results were obtained: Based on the results of previous studies, the article proposes a new model of computer network behavior over a period of time. This model is based on the principles of simulation modeling, which became possible because of the certain fractal properties of incoming traffic, that is one of the initial data for the simulation. In the process of development, the seven-level OSI model was taken as the basic network model and its four lower levels were selected. Ensuring reliable information transmission at all protocol levels is based on the mechanisms of acknowledgement and sliding window. The proposed model can reduce the amount of user data directly for each of the directions in a proportion directly proportional to their utilization of the specified congested channel. It is proposed to use a correction vector for each direction of information transmission in the model. Conclusions: The adequacy of the developed model is confirmed on the basis of practical calculations of the test case. The practical value of this model is the ability to predict bottlenecks when creating a computer network, or vice versa, to point out the redundancy of certain solutions in order to save significant funds in the future for providers and operators of communication services.