Point Projection Research Articles

Incentivization in centrally managed systems: Inconsistencies resolution

In centrally managed systems (CMSs), the need for incentivization systems at the local management level is crucial to optimize overall performance. Three alternative incentive systems have emerged within the centralized resource allocation (CRA) framework, aiming to measure the contribution of decision-making units (DMUs) in CMSs. However, we identify inconsistencies within these approaches and present them through illustrative examples. First, existing methods may struggle to effectively distinguish between CRA-efficient and CRA-inefficient DMUs, potentially resulting in inappropriate penalties or rewards for some the DMUs. Second, they may encounter difficulty in differentiating among CRA-efficient DMUs, especially when dealing with non-extreme DMUs or masked data within the dataset. Third, these methods may lack precision in measuring the impact of non-extreme CRA-efficient DMUs on overall performance. To address these limitations, we first highlight certain misconceptions related to individual efficiency within CMSs in the existing literature. Subsequently, we establish a fundamental characterization of individual efficient DMUs by outlining necessary and sufficient conditions for categorizing a DMU as CRA-efficient. For the second and third limitations, we adopt an endogenous perspective to quantify the influence of each CRA-efficient DMU. This involves calculating the maximum potential contribution of the DMU under evaluation in constructing the projection points of other DMUs. Furthermore, we propose a new method to handle masked data well in differentiating among CRA-efficient DMUs. We show the validity and applicability of our approaches using a real dataset.

A DSGE Model of the Russian Residential Real Estate Market

The paper develops a dynamic stochastic general equilibrium (DSGE) model of the Russian economy based on an endogenous housing sector and three categories of homeowners – patient, impatient and non-Ricardian. The DSGE model is applied from the first quarter of 2010 to the fourth quarter of 2019 using a Bayesian method for minimizing the discrepancy between theoretical and empirical impulse responses to a shock due to modified terms of trade. The model is then employed to provide a quantitative assessment of how macro variables respond to shocks generated by the housing market, interest rates, mortgage subsidies, financial liberalization, and altered terms of trade. At the same time, the impact of shocks on a number of economic indicators is largely determined by the functional form of household utility, as demonstrated by the robustness test. The results obtained based on the model also do not demonstrate a strong inertial effect in the economy due to the revival of the residential real estate construction sector, and they contradict a number of studies and expert estimates based primarily on the input-output model. One reason for this discrepancy may be the analysis, which is based on a horizontal supply curve, resulting in an overestimation of the impact of the construction sector on the economy. This DSGE model can serve as a starting point for scenario-based projections of the dynamics of the residential real estate market and the associated mortgage market, for testing the impact of various policy measures on the housing sector, and for assessing their effects on various categories of households.

Monocular Metasurface for Structured Light Generation and 3D Imaging with a Large Field-of-View.

Structured light three-dimensional (3D) imaging technology captures the geometric information on 3D objects by recording waves reflected from the objects' surface. The projection angle and point number of the laser dots directly determine the field-of-view (FOV) and the resolution of the reconstructed image. Conventionally, diffractive optical elements with micrometer-scale pixel size have been used to generate laser dot arrays, leading to limited FOV and point number within the projection optical path. Here, we theoretically put forward and experimentally demonstrate a monocular geometric phase metasurface composed of deep subwavelength meta-atoms to generate a 10 798 dot array within an FOV of 163°. Attributed to the vast number and high-density point cloud generated by the metasurface, the 3D reconstructed results showcase a maximum relative error in depth of 5.3 mm and a reconstruction error of 6.07%. Additionally, we propose a spin-multiplexed metasurface design method capable of doubling the number of lattice points. We demonstrate its application in the field of 3D imaging through experiments, where the 3D reconstructed results show a maximum relative depth error of 0.44 cm and a reconstruction error of 2.78%. Our proposed metasurface featuring advanced point cloud generation holds substantial potential for various applications such as facial recognition, autonomous driving, virtual reality, and beyond.

Research on the Protection Scheme of a High-Speed Railway Crossing 1000 KV Ultra-High Voltage Transmission Line

The high-speed railway project and the ultra-high-voltage transmission project represent two crucial components of China’s “new infrastructure”. As the construction of these two projects progresses rapidly, it is inevitable that instances of intersections will occur. Extreme conditions may cause damage to ultra-high voltage transmission cables. When a high-speed train passes by an ultra-high voltage transmission line, it poses a serious safety hazard. To address this issue, engineering examples were utilized to examine the protection structure scheme, protection distance, protection load, and construction procedures when a high-speed railway intersects a 1000 KV ultra-high voltage transmission line. A shed structure form and construction method for the electric power protection were proposed to ensure the safe operation of the high-speed railway while also achieving the safe and rapid construction of the high-speed railway protection structure in the safety zone of the approaching 1000 kV ultra-high voltage transmission line. The results indicated that the protection of high-speed railway crossings and 1000 kV ultra-high voltage transmission lines primarily focuses on line-break protection. The concrete shed structure with a straight wall and a flat roof was designed to meet the requirements of high-speed railway crossings. The line-break protection method enables the construction of an automatic warning protection corridor and a complete movable trolley quickly and safely within the safety zone near the transmission line. The implementation effect is, therefore, positive. It can be used as a reference point for other projects of a similar nature.

Adaptive projection plane and reference point strategy for multi-objective particle swarm optimization

Achieving a balance between convergence and diversity and their mutual enhancement is a complex task in the process of algorithm improvement. This is crucial because it is directly related to the effectiveness of the algorithm in obtaining accurate and uniformly distributed Pareto frontiers. Although significant progress has been made in particle swarm algorithms, exploring new approaches is necessary. In this paper, we construct a projection plane (projection line in 2D) based on the extreme values of the non-dominated solutions, select a set of uniform reference points on the projection plane, and then project the non-dominated solutions onto the constructed projection plane to form projection points. The reference points and projection points on the projection plane are thus utilized to guide the updating of the population as well as the maintenance of the external archive, a strategy that enhances the algorithm's global exploration and local exploitation capabilities. Secondly, we aggregate the target values of particles into a single scalar value and combine the idea of particle fusion to design a scheme for the particle selection of individual optimal particles. This paper further improves the algorithm's overall performance by using the information between populations to select individual optimal particles. Lastly, it is evaluated against a number of multi-objective algorithms that are currently in use and perform well on 22 test problems. The findings demonstrate that the algorithm this paper proposes performs better when solving multi-objective problems.

Criteria to select a research “topic” for postgraduate and doctoral studies in ayurveda

A research topic is a subject or problem that an investigator is interested in research. The starting point of any research project that is successful is a well-defined subject of research. The selection of topics is an ongoing approach in which investigators analyse, describe, classify, and refine their ideas. For the ease of selection of topics particularly in the field of Ayurveda, Authors have created an acronym ‘TOPIC’ as a guiding tool for the selection of the area of research. The components of the TOPIC criterion are Textual & Time-bound; Objectivity & Outcome measures; Planning & Pragmatic; Innovative & Interesting and Contemporarily relevant & Consent, highlight useful points for the easy selection of the topic for the research by the novice.

When are You Recovered? Defining Cutoff Points Using the Acute Respiratory Tract Infection Questionnaire

ObjectivesAcute respiratory tract infections (ARTIs) are a heterogenous group of diseases. Often, it is difficult to obtain a precise diagnosis in general practice but also difficult to determine when the patient is recovered. The lack of a precise definition of recovery after ARTI complicates scientific research aiming to optimize diagnostics and compare treatments. The study aimed to define cutoff points to determine the end of an ARTI as a proxy for recovery in patients diagnosed with ARTI in general practice using a validated patient-reported outcome instrument; The ARTI Questionnaire (ARTIQ). MethodsA total of 259 participants was divided in 2 groups—1 with ARTI and 1 without. Histograms and area under the curve were calculated for each of the 5 dimensions within the ARTIQ to evaluate the discriminative effect. For the most discriminative dimensions receiver operating comparison curves were performed to determine relevant cutoff points for having or not having ARTI symptoms and serve as a proxy for recovery in clinical research. ResultsThe highest discriminative effect was found in 2 dimensions: “physical—upper airways” and “physical—lower airways.” When combining these dimensions, the area under the curve was 0.97. Sensitivity, specificity, and predictive values were calculated for selected cutoff points. ConclusionCutoff points serving as proxy for recovery from ARTI using a patient-reported outcome were identified. The specific cutoff point for a certain research project must be selected considering the specific clinical situation of interest.

Dynamic Validation of Calibration Accuracy and Structural Robustness of a Multi-Sensor Mobile Robot.

For mobile robots, the high-precision integrated calibration and structural robustness of multi-sensor systems are important prerequisites for ensuring healthy operations in the later stage. Currently, there is no well-established validation method for the calibration accuracy and structural robustness of multi-sensor systems, especially for dynamic traveling situations. This paper presents a novel validation method for the calibration accuracy and structural robustness of a multi-sensor mobile robot. The method employs a ground-object-air cooperation mechanism, termed the "ground surface simulation field (GSSF)-mobile robot -photoelectric transmitter station (PTS)". Firstly, a static high-precision GSSF is established with the true north datum as a unified reference. Secondly, a rotatable synchronous tracking system (PTS) is assembled to conduct real-time pose measurements for a mobile vehicle. The relationship between each sensor and the vehicle body is utilized to measure the dynamic pose of each sensor. Finally, the calibration accuracy and structural robustness of the sensors are dynamically evaluated. In this context, epipolar line alignment is employed to assess the accuracy of the evaluation of relative orientation calibration of binocular cameras. Point cloud projection and superposition are utilized to realize the evaluation of absolute calibration accuracy and structural robustness of individual sensors, including the navigation camera (Navcam), hazard avoidance camera (Hazcam), multispectral camera, time-of-flight depth camera (TOF), and light detection and ranging (LiDAR), with respect to the vehicle body. The experimental results demonstrate that the proposed method offers a reliable means of dynamic validation for the testing phase of a mobile robot.

Spatial and temporal dynamics of thermal motion of a chain of liquid lead nanoinclusions attached to a fixed dislocation segment in an aluminum matrix

Thermal motion of a chain of liquid lead nanoinclusions attached to a dislocation segment fixed at its ends in the aluminum-based alloy was studied in situ using TEM in the temperature range from 442 °C to 497 °C. The projections of points of the trajectories of the inclusions onto the dislocation line were analyzed. The evidence for the collective interaction of all the inclusions and their spatially correlated collective thermal motion was obtained. Also, moderate temporal autocorrelation of thermal motion of the inclusions and a very weak temporal cross-correlation of thermal motion of the inclusions in all pairs was shown. The FFT phase spectra of the time dependencies of the inclusions positions on the dislocation segment give the evidence for the phase synchronization of thermal oscillations of the inclusions. It is shown that the thermal oscillations of the terminal inclusion attached to the dislocation node and elevation of temperature lead to decrease in the level of synchronization of thermal oscillations of the inclusions in the chain. It is indicated that the development of the process of desynchronization of thermal oscillations of the inclusions manifests itself by an increase in the density of phase steps in the initially linear unwrapped phase spectra accompanying by an increase in the interaction of the steps.

Reducing penumbral blur in computed tomography by learning the inverse finite focal spot model

Penumbral blur is one of the major limitations of the high spatial resolution micro-CT, due to a nonideal large focal spot. Penumbral blur hinders the ability to resolve small features that may only be a few pixels in size. Reducing the focal spot size by decreasing the x-ray tube power is a straightforward solution, but it leads to prolonged scan durations. In this paper, we propose to mitigate the penumbral blur by learning the inverse finite focal spot model. First, we derived the finite focal spot model that builds a relationship from the ideal point source projection to the finite focal spot projection. Based on the derived model, we numerically compute a paired projection dataset. Second, we utilized two neural networks—U-net, and convolution modulation-based U-net (CMU-net) —to learn the inverse finite focal spot model. The goal is to estimate the ideal point source projection from the actual finite focal spot projection. CMU-net, which introduces convolution modulation blocks into the contracting path of the U-net, is proposed to boost the robustness of the U-net. Finally, the standard filtered back-projection (FBP) is employed for reconstruction using the estimated ideal point projection. The experiments show that both U-net and CMU-net can effectively reduce the penumbral blur, whereas CMU-net demonstrates better performance on the real data. Experiments on real measured data demonstrate that CMU-net is more robust than U-net and can effectively resolve fine details. This method has great potential in improving the efficiency of micro-CT acquisition. It allows increasing the tube power since our method can computationally compensate for the blur caused by an increased focal spot size.

Multi-Scale Feature Fusion Point Cloud Object Detection Based on Original Point Cloud and Projection

Multi-Scale Feature Fusion Point Cloud Object Detection Based on Original Point Cloud and Projection

Correction for geometric distortion in the flattened representation of pipeline external surface

Conventional cameras often produce external pipeline surface images with significant perspective-projection distortions, making determining the type and size of defects on the pipeline surface difficult. To address this issue, we present a novel approach for correcting the geometric distortion of a constant diameter pipeline (CDP) external surface image based on apparent contour pairs (ACPs). First, the camera is calibrated and the real projection position of ACPs accurately extracted. Second, a single-view perspective projection model of the CDP is adopted to realize a three-dimensional reconstruction of the pipeline. Subsequently, the flattened image of the CDP’s outer surface is obtained by performing equidistant sampling of cross sections, determining the visibility of discrete points, and mapping projection points onto a flat surface. Simulations and real experiments demonstrated the high accurate method in the correction of CDP images. Experiments conducted under different outdoor scenarios confirmed the robustness of the proposed method.

Division of neuromuscular compartments and localization of the center of the highest region of muscle spindles abundance in deep cervical muscles based on Sihler's staining.

The overall distribution pattern of intramuscular nerves and the regions with the highest spindle abundance in deep cervical muscles have not been revealed. This study aimed to reveal neuromuscular compartmentalization and localize the body surface position and depth of the center of the region of highest muscle spindle abundance (CRHMSA) in the deep cervical muscles. This study included 36 adult cadavers (57.7 ± 11.5 years). The curved line joining the lowest point of the jugular notch and chin tip was designated as the longitudinal reference line (line L), and the curved line connecting the lowest point of the jugular notch and acromion was designated as the horizontal reference line (line H). Modified Sihler's staining, hematoxylin-eosin staining and computed tomography scanning were employed to determine the projection points (P) of the CRHMSAs on the anterior surfaces of the neck. The positions (PH and PL) of point P projected onto the H and L lines, and the depth of each CRHMSA, and puncture angle were determined using the Syngo system. The scalenus posterior and longus capitis muscles were divided into two neuromuscular compartments, while the scalenus anterior and longus colli muscles were divided into three neuromuscular compartments. The scalenus medius muscle can be divided into five neuromuscular compartments. The PH of the CRHMSA of the scalenus muscles (anterior, medius, and posterior), and longus capitis and longus colli muscles, were located at 36.27, 39.18, 47.31, 35.67, and 42.71% of the H line, respectively. The PL positions were at 26.53, 32.65, 32.73, 68.32, and 51.15% of the L line, respectively. The depths of the CRHMSAs were 2.47 cm, 2.96 cm, 2.99 cm, 3.93 cm, and 3.17 cm, respectively, and the puncture angles were 87.13°, 85.92°, 88.21°, 58.08°, and 77.75°, respectively. Present research suggests that the deep cervical muscles can be divided into neuromuscular compartments; we recommend the locations of these CRHMSA as the optimal target for administering botulinum toxin A injections to treat deep cervical muscle dystonia.

Using the Conditional Mean Direction in Estimating the Stability of Deformable Objects

Statement of the problem. During geodetic monitoring of the foundations of buildings and structures, quantitative characteristics of displacements of deformation marks are obtained. However, these data may contain errors due to the lack of a fixed initial basis. Thus it is proposed to use a conditional (fictitious) basis. Results. Using the example of a reactor ring, a conditional basis passing through the center of the reactor is considered, the projection of the conditional axis of the reactor onto a horizontal plane is taken as the starting point, and the conditional horizontal axis passing through the center of the reactor is taken as the direction. The calculation of the assessment of the stability of the signs of the basic planned altitude network and the assessment of the accuracy of determining the conditional axis of the reactor using these signs were performed. Conclusions. By changes in the value of the radius of the circumscribed circle, the deviation of the position of signs relative to the central point — the point of the corresponding projection of the conditional axis of the reactor — can be estimated.

Implementation of modified cam–clay model using closest point projection method under Cartesian coordinate system

The modified Cam–Clay model is an elastoplastic soil model that holds a prominent position in civil engineering for its precise depiction of varied soil behaviors. Despite extensive examination of its numerical processes, the predominant focus on stress integration algorithms within the triaxial stress space presents challenges for individuals less acquainted with geotechnical science. In response to this, the present study derived the stress integration equations for the modified Cam–Clay model within the Cartesian coordinate system employing the closest point projection method. Subsequently, a finite element program was developed incorporating the derived integration process. This study computed and compared the consolidation processes under both drained and undrained conditions for cubic soil samples with various over-consolidation ratios using the developed program, ABAQUS, and analytical formulas. The findings demonstrate that equations integrated within the Cartesian coordinate system offer ease of understanding and programming. The feasibility, accuracy, and stability of the closest point projection method have been validated. Comparative analysis of soil samples across various over-consolidation ratios indicated a reduction in failure stress with an increase in over-consolidation ratio, indicating a higher propensity for failure under undrained conditions than under the drained conditions.

Stability analysis and enhancement of super-efficiency model based on space distance

The traditional super-efficiency data Enveloping analysis (DEA) model can further distinguish the efficiency of efficient DMU. However, this distinction is unstable when there are perturbations in the efficient DMU inputs and outputs. The spatial distance can reflect the spatial variation of DMU on the envelope surface. We investigate the stability of the modified VRS super-efficiency model in the presence of data perturbations in efficiency DMUs and calculate its stability with spatial distances, providing a necessary and sufficient condition for such perturbations to affect the results of calculations of other efficient DMU super-efficiencies. A new super-efficiency model is proposed, which combines spatial distance to increase the constraint on projection point. Numerical examples are used to illustrate the model. On this basis, a spatial distance model for calculating inefficient DMU efficiency is further developed.

Posterior endpoint determination of the lumbar pedicle central axis on the anterior–posterior fluoroscopic image for pedicle screw insertion

The transpedicular procedure has been widely used in spinal surgery. The determination of the best entry point is the key to perform a successful transpedicular procedure. Various techniques have been used to determine this point, but the results are variable. This study was carried out to determine the posterior endpoint of the lumbar pedicle central axis on the standard anterior–posterior (AP) fluoroscopic images. Computer-aided design technology was used to determine the pedicle central axis and the posterior endpoint of the pedicle central axis on the posterior aspect of the vertebra. The standard AP fluoroscopic image of the lumbar vertebral models by three-dimensional printing was achieved. The endpoint projection on the AP fluoroscopic image was determined in reference to the pedicle cortex projection by the measurements of the angle and distance on the established X–Y coordinate system of the radiologic image. The projection of posterior endpoint of the lumbar pedicle central axis were found to be superior to the X-axis of the established X–Y coordinate system and was located on the pedicle cortex projection on the standard AP fluoroscopic image of the vertebra. The projection point was distributed in different sectors in the coordinate system. It was located superior to the X-axis by 18° to 26° at L1, while they were located superior to the X-axis by 12° to 14° at L2 to L5. The projections of posterior endpoints of the lumbar pedicle central axis were located in different positions on the standard AP fluoroscopic image of the vertebra. The determination method of the projection point was helpful for selecting an entry point for a transpedicular procedure with a fluoroscopic technique.

Non-dispensing pharmacists integrated into general practices as a new interprofessional model: a qualitative evaluation of general practitioners’ experiences and views

BackgroundA new interprofessional model incorporating non-dispensing pharmacists in general practice teams can improve the quality of pharmaceutical care. However, results of the model are dependent on the context. Understanding when, why and how the model works may increase chances of successful broader implementation in other general practices. Earlier theories suggested that the results of the model are achieved by bringing pharmacotherapeutic knowledge into general practices. This mechanism may not be enough for successful implementation of the model. We wanted to understand better how establishing new interprofessional models in existing healthcare organisations takes place.MethodsAn interview study, with a realist informed evaluation was conducted. This qualitative study was part of the Pharmacotherapy Optimisation through Integration of a Non-dispensing pharmacist in primary care Teams (POINT) project. We invited the general practitioners of the 9 general practices who (had) worked closely with a non-dispensing pharmacist for an interview. Interview data were analysed through discussions about the coding with the research team where themes were developed over time.ResultsWe interviewed 2 general practitioners in each general practice (18 interviews in total). In a context where general practitioners acknowledge the need for improvement and are willing to work with a non-dispensing pharmacist as a new team member, the following mechanisms are triggered. Non-dispensing pharmacists add new knowledge to current general practice. Through everyday talk (discursive actions) both general practitioners and non-dispensing pharmacists evolve in what they consider appropriate, legitimate and imaginable in their work situations. They align their professional identities.ConclusionsNot only the addition of new knowledge of non-dispensing pharmacist to the general practice team is crucial for the success of this interprofessional healthcare model, but also alignment of the general practitioners’ and non-dispensing pharmacists’ professional identities. This is essentially different from traditional pharmaceutical care models, in which pharmacists and GPs work in separate organisations. To induce the process of identity alignment, general practitioners need to acknowledge the need to improve the quality of pharmaceutical care interprofessionally. By acknowledging the aspect of interprofessionality, both general practitioners and non-dispensing pharmacists will explore and reflect on what they consider appropriate, legitimate and imaginable in carrying out their professional roles.Trial registrationThe POINT project was pre-registered in The Netherlands National Trial Register, with Trial registration number NTR-4389.

Anatomical and topographic features of the gluteal muscle group of extensors and rotators of the hip joint in a Maine Coon cat

The article presents the anatomical features of the gluteal group of extensors and supinators of the hip joint in a Maine Coon cat, which are absent in the available literature. The Maine Coon is the largest of the numerous breeds of domestic cats. To date, the anatomy of cats, and even more so the age, sex, breed, and species characteristics remain poorly understood, while the study of the specific anatomical features of the pelvic limb muscles in animals is one of the urgent tasks in the field of comparative anatomy and practical veterinary medicine. We have established that the muscles of the gluteal extensor group belong to different types of muscles: the middle gluteal is dynamic, the additional and deep gluteal, the pear–shaped is dynamostatic, with appropriate functional abilities. The research was carried out at the Department of Anatomy and Histology of Animals named after Professor A.F. Klimov, Moscow State Academy of Veterinary Medicine and Biotechnology – MBA named after K.I. Scriabin."The sectional material – pelvic limbs (n=8), selected from a domestic cat, without external signs of musculoskeletal pathologies, served as a material for research. Methods of fine macro- and microanatomic dissection were used, followed by functional analysis of the studied structures and skeletotopic projection of points of attachment of muscle parts. On the basis of the conducted research, we have established the skeleto-topical features of the anatomical formations on the pelvic and femur bones. It has been convincingly shown that the main extensor of the hip joint in the Maine Coon is the gluteus medius muscle. It is the most powerful among the gluteal muscles and belongs to the dynamic type in its internal structure. At the same time, the additional gluteus muscle, being a muscle of the dynamo-static type, performs a more static function of the joint, that is, when it is extended, it holds the joint in this position for a longer time. The piriformis and deep gluteus muscles, anchored by the bases at different levels, are synergists in hip abduction.

Structure-based identification of salicylic acid derivatives as malarial threonyl tRNA-synthetase inhibitors.

Emerging resistance to existing antimalarial drugs drives the search for new antimalarials, and protein translation is a promising pathway to target. Threonyl t-RNA synthetase (ThrRS) is one of the enzymes involved in this pathway, and it has been validated as an anti-malarial drug target. Here, we present 9 structurally diverse low micromolar Plasmodium falciparum ThrRS inhibitors that were identified using high-throughput virtual screening (HTVS) and were verified in a FRET enzymatic assay. Salicylic acid-based compound (LE = 0.34) was selected as a most perspective hit and was subjected to hit-to-lead optimisation. A total of 146 hit analogues were synthesised or obtained from commercial vendors and were tested. Structure-activity relationship study was supported by the crystal structure of the complex of a salicylic acid analogue with a close homologue of the plasmodium target, E. coli ThrRS (EcThrRS). Despite the availability of structural information, the hit identified via virtual screening remained one of the most potent PfThrRS inhibitors within this series. However, the compounds presented herein provide novel scaffolds for ThrRS inhibitors, which could serve as starting points for further medicinal chemistry projects targeting ThrRSs or structurally similar enzymes.