Indoor Detection and Tracking of People Using mmWave Sensor

This paper proposes a new indoor people detection and tracking system using a millimeter-wave (mmWave) radar sensor. Firstly, a systematic approach for people detection and tracking is presented—a static clutter removal algorithm used for removing mmWave radar data’s static points. Two efficient clustering algorithms are used to cluster and identify people in a scene. The recursive Kalman filter tracking algorithm with data association is used to track multiple people simultaneously. Secondly, a fast indoor people detection and tracking system is designed based on our proposed algorithms. The method is lightweight enough for scalability and portability, and we can execute it in real time on a Raspberry Pi 4. Finally, the proposed method is validated by comparing it with the Texas Instruments (TI) system. The proposed system’s experimental accuracy ranged from 98% (calculated by misclassification errors) for one person to 65% for five people. The average position errors at positions 1, 2, and 3 are 0.2992 meters, 0.3271 meters, and 0.3171 meters, respectively. In comparison, the Texas Instruments system had an experimental accuracy ranging from 96% for one person to 45% for five people. The average position errors at positions 1, 2, and 3 are 0.3283 meters, 0.3116 meters, and 0.3343 meters, respectively. The proposed method’s advantage is demonstrated in terms of tracking accuracy, computation time, and scalability.

A New Gaze Estimation Method Based on Homography Transformation Derived from Geometric Relationship

In recent years, the gaze estimation system, as a new type of human-computer interaction technology, has received extensive attention. The gaze estimation model is one of the main research contents of the system. The quality of the model will directly affect the accuracy of the entire gaze estimation system. To achieve higher accuracy even with simple devices, this paper proposes an improved mapping equation model based on homography transformation. In the process of experiment, the model mainly uses the “Zhang Zhengyou calibration method” to obtain the internal and external parameters of the camera to correct the distortion of the camera, and uses the LM(Levenberg-Marquardt) algorithm to solve the unknown parameters contained in the mapping equation. After all the parameters of the equation are determined, the gaze point is calculated. Different comparative experiments are designed to verify the experimental accuracy and fitting effect of this mapping equation. The results show that the method can achieve high experimental accuracy, and the basic accuracy is kept within 0.6∘. The overall trend shows that the mapping method based on homography transformation has higher experimental accuracy, better fitting effect and stronger stability.

Radiation pressure measurement using a macroscopic oscillator in an ambient environment

In contrast to current efforts to quantify the radiation pressure of light using nano-micromechanical resonators in cryogenic conditions, we proposed and experimentally demonstrated the radiation pressure measurement in ambient conditions by utilizing a macroscopic mechanical longitudinal oscillator with an effective mass of the order of 20 g. The light pressure on a mirror attached to the oscillator was recorded in a Michelson interferometer and results showed, within the experimental accuracy of 3.9%, a good agreement with the harmonic oscillator model without free parameters.

Barrier to internal rotation, symmetry and carbonyl reactivity in methyl 3,3,3-trifluoropyruvate

High-resolution rotational spectroscopy was used to investigate the conformational landscape of methyl-3,3,3-trifluoropyruvate, a small, partially-fluorinated molecule, which is of interest because of its chemical properties and reactivity in contrast to the unfluorinated species. Methyl 3,3,3-trifluoropyruvate is also subject to two possible large amplitude motions of the methyl and trifluoromethyl group. However, only the methyl rotor gives rise to the tunneling splitting specific to individual conformers. In the rotational spectrum measured in the frequency region from 6 to 27 GHz, the identified conformers, s-cis and s-trans, were fitted to experimental accuracy, resulting in the accurate determination of the vibrational ground state rotational constants ${A}_{0}=2185.05827\left(36\right)\text{\hspace{0.17em}MHz}$, ${B}_{0}=1023.30031\left(17\right)\text{\hspace{0.17em}MHz}$, and ${C}_{0}=803.520287\left(95\right)\text{\hspace{0.17em}MHz}$ for the s-cis conformer, and ${A}_{0}=2706.9024\left(49\right)\text{\hspace{0.17em}MHz}$, ${B}_{0}=864.889539\left(81\right)\text{\hspace{0.17em}MHz}$, and ${C}_{0}=746.532896\left(71\right)\text{\hspace{0.17em}MHz}$ for the s-trans conformer. Additionally the barrier heights of the methyl rotor ${V}_{3}\left({\text{CH}}_{3}\right)=363.116\left(94\right){\text{\hspace{0.17em}cm}}^{-1}$ and ${V}_{3}\left({\text{CH}}_{3}\right)=389.290\left(80\right){\text{\hspace{0.17em}cm}}^{-1}$ were obtained for the s-cis and s-trans conformer, respectively.

Necessity of the inclusion of borders in value of cultivation and use trials in upland rice

Experimental accuracy in crop research is directly affected by the size of plots. For this reason, researchers use empirical knowledge to determine plot size. There are also other important aspects for determining ideal plot size. These include the type of crop and the use, or not, of borders. The objective of this research was to verify the necessity of including border material in the value of cultivation and use trials in breeding programs of upland rice and to evaluate the experimental accuracy with and without the inclusion of borders. The research was conducted in an experimental area at the Federal University of Lavras, located in the State of Minas Gerais, during three harvests (2014/2015, 2015/2016, 2016/2017). Thirteen upland rice strains and methods of evaluation (useful area and border) were evaluated. A randomized complete block design with three replications was used to evaluate grain yield. Individual analyses of variance were performed considering the useful areas and the borders for the three agricultural years. A joint analysis was also performed with the use of a subdivided plot involving the location of the harvest in terms of the useful area and border among the rice strains. It was concluded it is necessary to use borders in the value of cultivation and use trials in breeding programs of upland rice as it contributes to the performance and experimental accuracy of research results.

Plot Size by the Variance Comparison Method for With ‘Gigante’ Cactus Pear

Appropriate plot size is recognized as a means of maximizing experimental accuracy and contributes to efficient treatment assessment. This study aimed to estimate the optimal plot size for experiments with ‘Gigante’ cactus pears using the comparison of variances method (CVM). A uniformity trial was conducted to assess plant height (PH), number of cladodes (NC), yield (Y), cladode area index (CAI), cladode length (CL), width (CW), thickness (CT) and cladode area (CA) in a cactus pear crop. A rectangular-shaped plot consisting of 10 rows of 50 plants each was used, totaling 500 plants, with 384 basic units (BU), corresponding to the study area. A hierarchical classification approach was adopted, simulating a split-plot design in which each plant was denominated a basic unit (BU), and considering the effects of blocks (B), plots (P)/B, subplots (S)/P/B, rows (R)/S/P/B and plants (Pln)/F/S/P/B. This resulted in five plots sizes, consisting of 1, 12, 24, 48 and 96 basic units. Plots with 12, 24, 48 and 96 BU were statistically equal for the variables Y, PH, NC, CAI, CL, CW and CT, with lower variances than the plot with 1 BU. As such, 4.8 m² with 12 basic units is the optimal experimental plot size for ‘Gigante’ cactus pears.