This article presents a self-referencing lookup table (LUT) algorithm to enhance the multiturn accuracy of a battery-free multiturn absolute magnetic encoder. The encoder consists of a single-turn ...angle for the measurement of the degree of rotation within <inline-formula> <tex-math notation="LaTeX">2\pi </tex-math></inline-formula> using a multipolar magnet to achieve high resolution and a multiturn counter to monitor the total number of revolutions made by the encoder's shaft through the different angles of the four bipolar magnets (BPMs) based on four-shaft gears. However, the signals from the BPMs are affected by factors, such as amplitude mismatch, dc offsets, random noises, and harmonic components that are as a result of electrical and mechanical distortions. To solve this problem, this article suggested a method derived from the single-turn angle and the raw signals from the BPMs to generate the LUTs for multiturn angles. These angles eliminate the effects of the disturbances. Additionally, a multiturn compensation algorithm is suggested to compensate for the number of revolutions made by the encoder. The proposed methods are simulated in MATLAB software and implemented in ARM STM32F407ZG. The effectiveness of the proposed method is demonstrated by the obtained results.
The Nida valley study area underwent examination to investigate the hydrochemical components and the correlation between groundwater (GW) and surface water (SW). Over a 12-month period from November ...2021 to October 2022, 9 monitoring points were established, consisting of 7 GW points and 2 SW points, with a monitoring frequency of once per month. The research findings indicate that the hydrochemical components and direction of GW flow in the study area can be classified into 3 distinct regions. The chemical composition is complex in areas near the Nida River, stable in the region near the Smuga Umianowicka branch, and different in other areas. It was observed that the SW in the Nida River and Smuga Umianowicka branch exhibits a relatively uncomplicated chemical composition due to minimal human impact in the natural area. However, dissimilarities between them were also identified and explained by the flow regulation of the dam built on the branch within the study area. The application of the Shapiro-Wilk test (α = 0.05) and Kruskal-Wallis test (α = 0.05) revealed statistically significant differences among the recorded hydrochemical component values throughout the measurement period. Furthermore, Pearson’s correlation coefficient analysis (α = 0.001) indicated correlations between the hydrochemical components of SW and GW in the riparian area and strong correlations among GW samples. Principal Component Analysis (PCA) identified significant dissimilarity and similarity between GW and SW samples based on their characteristics.
Stara Nida represents one of the three hydrological channels traversing the Nadnidziański Landscape Park, a locale characterized by ecological diversity within the Nida valley, Poland. Historically ...rendered inactive due to flow regulation, this specific river branch underwent restoration in February 2023 as a pivotal component of the "Restoration of the Inland Delta of the Nida River" project. The revitalization of Stara Nida has precipitated beneficial ecological metamorphoses within the landscape. To evaluate the impact of the restoration of the Stara Nida branch on the physicochemical characteristics of water in the landscape, systematic sampling of regional SW and GW was conducted. The sampling duration covered a 12-month period, segmented into two phases: the first six months leading up to the restoration (from February 2022 to July 2022) and the subsequent six months following the restoration of the Stara Nida branch (from February 2023 to July 2023). A total of 114 water samples were collected from 10 distinct sampling locations. In-situ measurements of key indicators, including temperature (T), electrical conductivity (EC), dissolved oxygen (DO), pH, and total dissolved solids (TDS), were performed using handheld devices. Concurrently, laboratory analyses were carried out for total nitrogen (TN), total phosphorus (TP), chloride (Cl–), sulfate (SO42–), manganese (Mn2+), iron (Fe2+,3+), zinc (Zn2+), cadmium (Cd2+), lead (Pb2+), copper (Cu2+), and chemical oxygen demand (COD). Statistical analyses encompassed the Shapiro–Wilk test (α = 0.05) and the Wilcoxon (Mann–Whitney) rank sum test (α = 0.05) to discern significant disparities in physicochemical indicators at sampling points pre- and post-restoration of the Stara Nida branch. Additionally, Pearson correlation analysis (α = 0.001) was employed to evaluate overarching changes at the sampling points attributable to the impact of the Stara Nida branch restoration.
The study area of the Nida valley was examined to investigate variations in groundwater and surface water levels, as well as the interaction between them. In the valley, there were three branches. ...The two actives were the Nida River itself and the Smuga Umianowicka branch while the Stara Nida branch was dry during the measurement session. Over a 12-month period from June 2021 to June 2022, 7 monitoring points were equipped with piezometers, comprising 5 groundwater points and 2 surface water points. The monitoring frequency was set to 30 minutes. The results of this research indicate that there are significant differences in the water level at the same observed point at different times. This study demonstrates seasonal changes in both surface water and groundwater levels with higher levels in autumn and winter and lower levels in spring and summer, which are closely tied to the changes in meteorological conditions during the research period, such as precipitation and air temperature. The study results also indicate that during summer and winter at the Nida River and its riparian area, losing stream is the primary process occurring in the studied reach. Conversely, during autumn and spring, the main process is gaining stream. At the human-maintained Smuga Umianowicka branch and in its riparian area, losing stream is the main process during summer and autumn, and gaining stream is the main process during spring. During winter, losing stream and gaining stream processes can occur simultaneously, and neither process takes place mainly.
The groundwater of the Nida valley was investigated to assess the quality of water source and monthly variations of the physicochemical parameters. A total of 70 water samples were collected from 7 ...sampling sites during a 10 months period from June 2021 to March 2022. Sampling frequency was once per month. The parameters such as temperature ( T), electrical conductivity ( EC), dissolved oxygen (DO), pH, total dissolved solids (TDS) were measured in-situ by using handheld device. Meanwhile, total nitrogen (TN), total phosphorus (TP), chloride (Cl –), sulphate (SO42–), manganese (Mn), iron (Fe), zinc (Zn), cadmium (Cd), lead (Pb), copper (Cu), chemical oxygen demand (COD) were analysed in the laboratory. According to the classification of Ministry of Marine Economy and Inland Navigation in Poland (2019), some investigated parameters are classified as unsatisfactory quality waters (class 4) and poor-quality waters (class 5) for a few specific months. Such as, TP concentrations obtained in June and January are classified as class 4, SO 4 2– concentrations corresponded to classes 4 and 5 in June, July and August, and Mn concentrations (except in January) are settled in class 5. The high values of Fe in November are arranged in class 5 and in June, July to September and March are classified in class 4. Statistical methods were used as: Shapiro–Wilk test (α = 0.05), ANOVA test and post-hoc Tukey test (α = 0.05), Kruskal–Wallis test and Wilcoxon (Mann–Whitney) rank sum test (α = 0.05) estimated the significant differences in sampling months. Pearson correlation analysis (α = 0.01 and 0.05), principal component analysis (PCA) and cluster analysis showed correlation between the parameters and sampling months.
The investigation of Nida Valley water aimed to assess fluctuations in physicochemical properties. In this study, environmental monitoring method was utilized to evaluate the changes in ...physicochemical properties of water. Over a 24-month period, from June 2021 to May 2023, a total of 228 water samples were collected from 10 sampling sites, with a monthly sampling frequency. Statistical analyses were utilized including the Shapiro–Wilk test (α = 0.05), Kruskal–Wallis test and Wilcoxon (Mann–Whitney) rank sum test (α = 0.05), Pearson correlation analysis (α = 0.001) and principal component analysis (PCA). Statistical analyses revealed significant differences between months in GW samples for for temperature, dissolved oxygen, pH, total nitrogen, total phosphorus, chloride, manganese, and zinc in GW samples and for T and DO in SW samples. Pearson correlation coefficient analysis (α = 0.001) identified strong positive correlations within the SW dataset. Similarly, significant positive correlations were observed among the GW dataset. Noteworthy positive correlations were also detected between the GW and SW datasets. Principal component analysis (PCA) revealed a substantial dissimilarity between GW2 samples compared to others, characterized by elevated manganese, iron, and Sulfate content. Two distinct groups emerged: Group 1 included samples at GW1, GW2, GW3, GW5, and SW2, while Group 2 comprised all other samples. This study demonstrated the stability in the physicochemical properties of SW and underscore a discernible correlation between the hydrochemical compositions of both SW and GW in the riparian area. Outstanding characteristics in hydrochemical component of sample waters have been indicated.
The task of object pose estimation in computer vision heavily relies on both color (RGB) and depth (D) images to provide crucial appearance and geometric information, assisting algorithms in ...understanding occlusions and object geometry, thereby enhancing accuracy. However, the dependency on specialized sensors capable of capturing depth poses challenges in terms of cost and availability. Consequently, researchers are exploring methods to estimate object poses solely from RGB images. Nevertheless, this approach encounters difficulties in handling occlusions, discerning object geometry, and resolving ambiguities arising from similar color or texture patterns. This paper introduces a novel geometry-aware method for object pose estimation utilizing RGB images as input to determine the poses of multiple object instances. Our approach leverages both depth and color images during training but only relies on color images during inference. Departing from traditional depth sensors, our method computes predicted point clouds directly from estimated depth images derived from RGB inputs. A key innovation lies in the formulation of a multi-scale fusion module adept at seamlessly integrating features extracted from RGB images with those inferred from the predicted point clouds. This fusion process significantly fortifies the pose estimation pipeline by harnessing the strengths of both modalities, resulting in notably improved object poses. Extensive experimentation demonstrates that our approach markedly outperforms state-of-the-art RGB-based methods on Occluded-LINEMOD and YCB-Video datasets. Moreover, our method achieves competitive results compared to RGB-D approaches that necessitate both RGB and depth data from physical sensors.
Biphasic calcium phosphate (BCP) is an ideal bone substitute with controllable bioresorption/biodegradation by changing its relative amount of hydroxyapatite (HA) and β-tricalcium phosphate (β-TCP) ...compositions. This study investigated the effect of synthetic conditions on the physicochemical properties and the remineralization behaviors of BCP materials in artificial saliva (AS). BCPs were obtained under the sonochemical condition at pH of 5.0 (BCP_5), 7.0 (BCP_7), and 9.0 (BCP_9), and all were sintered at 800, 1000, and 1200 °C. The HA/β-TCP ratio of BCPs increased according to the pH increase during the synthesis process. BCP_5 sintered at 800 °C with the highest β-TCP contents demonstrated (1) fast neutralization capacity to prevent enamel from dissolving in acidic saliva and (2) remineralization ion supply, and (3) new apatite formation found in acidic AS, indicating its high potential remineralization agent for dental care applications.
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•BCPs synthesized at pH 5.0 with high β-TCP had fast neutralization capacity in acidic saliva and ion supply.•BCPs synthesized at pH 5.0 generated new apatite formation in acidic and neutral artificial saliva.•BCPs sintered at 800 and 1000 °C achieved better remineralization properties than 1200 °C.
Fifteen steroids, including two new compounds, leptosteroid (1) and 5,6β-epoxygorgosterol (2), were isolated and structurally elucidated from the Vietnamese soft coral Sinularia leptoclados. Their ...cytotoxic effect against a panel of eight human cancer cell lines was evaluated using sulforhodamine B (SRB) method. Significant cytotoxicity against hepatoma cancer (HepG2, IC50=21.13±0.70 µM) and colon adenocarcinoma (SW480, IC50=28.65±1.53 µM) cell lines were observed for 1 and against acute leukemia (HL-60, IC50=20.53±2.26 µM) and SW480 (IC50=26.61±1.59 µM) for ergost-5-en-3β,7β-diol (8). In addition, 3β,7β-dihydroxyergosta-5,24(28)-diene (13) showed significant cytotoxic activity on all tested cell lines with IC50 values ranging from 13.45±1.81 to 29.01±3.21 µM.
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