Quality estimation and optimization of adaptive stereo matching algorithms for smart vehicles

Stereo matching is a promising approach for smart vehicles to find the depth of nearby objects. Transforming a traditional stereo matching algorithm to its adaptive version has potential advantages to achieve the maximum quality (depth accuracy) in a best-effort manner. However, it is very challenging to support this adaptive feature, since (1) the internal mechanism of adaptive stereo matching (ASM) has to be accurately modeled, and (2) scheduling ASM tasks on multiprocessors to generate the maximum quality is difficult under strict real-time constraints of smart vehicles. In this article, we propose a framework for constructing an ASM application and optimizing its output quality on smart vehicles. First, we empirically convert stereo matching into ASM by exploiting its inherent characteristics of disparity–cycle correspondence and introduce an exponential quality model that accurately represents the quality–cycle relationship. Second, with the explicit quality model, we propose an efficient quadratic programming-based dynamic voltage/frequency scaling (DVFS) algorithm to decide the optimal operating strategy, which maximizes the output quality under timing, energy, and temperature constraints. Third, we propose two novel methods to efficiently estimate the parameters of the quality model, namely location similarity-based feature point thresholding and street scenario-confined CNN prediction. Results show that our DVFS algorithm achieves at least 1.61 times quality improvement compared to the state-of-the-art techniques, and average parameter estimation for the quality model achieves 96.35% accuracy on the straight road

Comparison of the Preparation Process of Rare Earth Oxides from the Water Leaching Solution of Waste Nd-Fe-B Magnets’ Sulfate Roasting Products

The new process developed here consisting of sulfurization roasting transformation and water immersion can effectively realize the separation of rare earth elements (REEs) and impurities from spent Nd-Fe-B magnets. For the industrial application of the new process, it is critical to determine how to economically and efficiently prepare rare earth oxide (RExOy) products with higher purity from the obtained water leaching solution. Therefore, according to rare earth sulfate (RE2(SO4)3) solution characteristics, the oxalic acid precipitation–calcination method, sodium carbonate precipitation–calcination method, and double sulfates precipitation–alkali conversion–calcination method were optimized and compared. The results show that the recovery efficiency of REE recovery via the oxalic acid precipitation–calcination method is 99.44%, and the purity of RExOy is 99.83% under optimal technological conditions. However, the cost of oxalic acid precipitation is higher. The process consisting of the double sulfates precipitation–alkali conversion–calcination method is relatively complicated, the recovery efficiency of REEs is 97.95%, and the purity of the RExOy is 98.04%. The recovery efficiency of the REEs and the purity of the RExOy obtained from the sodium carbonate precipitation–calcination method are 99.12% and 98.33%, respectively. Moreover, the recycling cost of sodium carbonate precipitation is the lowest among the three processes for preparing RExOy, so it has industrial application potential. The obtained results for REE recovery from spent Nd-Fe-B magnets in this research can provide theoretical guidance for the innovation of the recycling process for REEs as secondary resources

Selective Separation and Recovery of Li from Spent LiFePO₄ Cathode Materials by Oxidation Roasting Followed by Low-Acid Pressure Leaching

The environmental and economic benefits of recycling spent LiFePO4 batteries are becoming increasingly important. Nevertheless, the reprocessing of this type of material by conventional processes remains a challenge due to the difficulties of Li and Fe separation and low product purity. Herein, a new approach for recovering Li to separate iron and phosphorus from spent LiFePO4 cathode materials is developed. Selective separation of Li can be achieved by oxidation roasting followed by low-acid pressure leaching. During the oxidation-roasting stage, almost all the stable LiFePO4 cathode materials were first transformed into Li3Fe2(PO4)3 and Fe2O3, with the most suitable oxidation-roasting temperature determined to be 550 °C. Then, >96% of Li could be extracted using 0.5 mol·L−1 H2SO4 with an L/S ratio of 150 g·L−1 at 110 °C for 1 h; in contrast, the leaching of Fe was 0.03%. The mineral-phase composition of the leaching residues mainly includes FePO4·2H2O, Fe2O3, and C, which can be used as a raw material for preparing battery-grade FePO4. These findings demonstrate that the recycling process has the advantages of high selectivity for Li, excellent reaction kinetics, low acid consumption, and free oxidizing agent that may benefit the development of a circular economy

Decreased Plasma Nesfatin-1 Level Is Related to the Thyroid Dysfunction in Patients with Type 2 Diabetes Mellitus

Aims. Thyroid dysfunction is frequently observed in patients with type 2 diabetes mellitus (T2DM), but the underlying mechanism is still poorly understood. The present study aimed to investigate whether nesfatin-1 played a role in the thyroid dysfunction in patients with T2DM. Methods. 55 euthyroid patients were enrolled in this study including 30 patients with T2DM and 25 patients with impaired glucose regulation (IGR). 30 age-matched healthy people were also included as the control. The plasma levels of nesfatin-1, thyrotropin (TSH), and glycosylated hemoglobin (HbA1c) as well as the body mass index (BMI) were comparatively analyzed among the three groups. Results. The nesfatin-1 was significantly lower in patients with T2DM than in patients with IGR and in the control. On the contrary, the TSH level was significantly higher in patients with T2DM than in patients with IGR and in the control. Simple regression analysis showed that the plasma nesfatin-1 was negatively correlated with the TSH and HbA1c levels and positively correlated with the BMI. With multiple stepwise regression analysis, the nesfatin-1 remained to be independently correlated with the TSH, BMI, and HbA1c. Conclusions. The study was suggesting a role of nesfatin-1 in thyroid dysfunction in patients with T2DM

A portable analog lock-in amplifier for accurate phase measurement and application in high-precision optical oxygen concentration detection

Abstract A portable analog lock-in amplifier capable of accurate phase detection is proposed in this paper. The proposed lock-in amplifier, which uses the dual-channel orthometric signals as the references to build the xy coordinate system, can detect the relative phase between the input and x-axis based on trigonometric function. The sensitivity of the phase measurement reaches 0.014 degree, and a detection precision of 0.1 degree is achieved. At the same time, the performance of the lock-in amplifier is verified in the high precision optical oxygen concentration detection. Experimental results reveal that the portable analog lock-in amplifier is accurate for phase detection applications. In the oxygen sensing experiments, 0.058% oxygen concentration resulted in 0.1 degree phase shift detected by the lock-in amplifier precisely. In addition, the lock-in amplifier is small and economical compared with the commercial lock-in equipments, so it can be easily integrated in many portable devices for industrial applications

Separation of Li and Al from spent ternary Li-ion batteries by in-situ aluminum‑carbon reduction roasting followed by selective leaching

Publisher Copyright: © 2022 Elsevier B.V.During the reduction roasting of waste ternary Li-ion batteries (LIBs), a large amount of carbon reductant is introduced in the recycling process, which is not conductive to achieve the goal of carbon peaking and carbon neutrality. This research proposes to make full use of aluminum and carbon – main constituents of waste LIBs – as reductants in the roasting process. Results show that the aluminum-carbon reduction roasting method has a higher efficiency compared with the traditional carbon reduction. Lithium present in ternary materials can be almost completely transformed into soluble Li2CO3, while the associated Ni, Co and Mn are all converted into insoluble metal elements or their corresponding oxides at 650 °C (t = 90 min). The presence of Al decreases the carbothermal roasting temperature, while the presence of waste carbon allows Li to be converted into easily soluble lithium carbonate in preference to lithium aluminate. The optimal amount of carbon and Al in the spent LIBs were 14.7% and 7.0%, respectively. After roasting, > 97% of Li could be selectively leached by carbonated water leaching, while only 99% Al separation. These results suggest that the in-situ aluminum-carbon reduction roasting, followed by selective leaching of Li and Al, mitigates several of the challenges related to battery recycling: (i) Li extraction is increased substantially above the state-of-the-art recovery efficiencies, (ii) Al - known to decrease battery metals extraction in hydrometallurgical processing - is selectively removed after making full use of its reducibility and (iii) battery metal-rich residues with low impurity levels is produced for further refining, therefore paving the way towards more economical, efficient and environmentally friendly spent LIBs recycling.Peer reviewe

Selective lithium recovery and integrated preparation of high-purity lithium hydroxide products from spent lithium-ion batteries

The current paper presents an innovative route for selective lithium extraction, followed by production of battery grade LiOH·H 2O via reductive hydrogen roasting, water leaching and LiOH·H 2O crystallization. The results suggest that during the initial hydrogen reduction stage, almost 98% of Li can be transformed into soluble LiOH·H 2O with H 2 reduction at 500 °C within 15 min, while Ni, Co, Mn all transform into their corresponding insoluble metals or their oxides. Consequently, almost all of Li present in the roasted material can be effectively separated from other impurities by 10 min of water leaching at 25 °C with liquid-solid (L/S) ratio of 2, such that the extraction of other metals like Ni, Co, Mn are < 0.1%. Subsequent stages allow high purity LiOH·H 2O (99.92%) to be obtained directly through evaporation and crystallization. In addition, high nickel battery cathode materials (LiNi 0.8Co 0.1Mn 0.1O 2) are prepared from the recycled LiOH·H 2O products and these demonstrate good electrochemical performance. Overall, this newly developed hydrogen reduction-based process may provide a more simple, efficient and environmental friendlier method for the recovery of valuable metals from spent LIBs, as well as offering great potential for straightforward industrial-scale recycling.Peer reviewe

MTR-SAM: Visual Multimodal Text Recognition and Sentiment Analysis in Public Opinion Analysis on the Internet

Existing methods for monitoring internet public opinion rely primarily on regular crawling of textual information on web pages but cannot quickly and accurately acquire and identify textual information in images and videos and discriminate sentiment. The problems make this a challenging research point for multimodal information detection in an internet public opinion scenario. In this paper, we look at how to dynamically monitor the internet opinion information (mostly images and videos) that different websites post. Based on the most recent advancements in text recognition, this paper proposes a new method of visual multimodal text recognition and sentiment analysis (MTR-SAM) for internet public opinion analysis scenarios. In the detection module, a LK-PAN network with large sensory fields is proposed to enhance the CML distillation strategy, and an RSE-FPN with a residual attention mechanism is used to improve feature map representation. Second, it proposes that the original CTC decoder be replaced with a GTC method to solve earlier problems with text detection at arbitrary rotation angles. Additionally, the performance of scene text detection for arbitrary rotation angles is improved using a sinusoidal loss function for rotation recognition. Finally, the improved sentiment analysis model is used to predict the sentiment polarity of the text recognition results. The experimental results show that the new method proposed in this paper improves recognition speed by 31.77%, recognition accuracy by 10.78% on the video dataset, and the F1 score of the multimodal sentiment analysis model by 4.42% on the self-built internet public opinion dataset (lab dataset). The method proposed provides significant technical support for internet public opinion analysis in multimodal domains

Foliar Application of Chitosan Accelerates Wound Periderm Formation with an Intensified Deposition of Suberin Polyphenolic and Lignin in the Wounds of Potato Tubers

Potato tubers are susceptible to wounding during post-harvest processes, leading to quality decline, perishability and large economic losses. In this study, the potato cultivar, ‘Longshu No.7′, was foliar-sprayed with 3% chitosan (w/v) three times during the pre-harvest period after flowering to evaluate the effect of foliar spraying with chitosan on suberization processing in the wounds of harvested potato tubers. Our results demonstrated that foliar sprayed with chitosan significantly reduced wound-induced fresh weight loss and dry rot disease index by 37.34% and 41.60% on day 28 after wounding, respectively. Foliar sprayed with chitosan accelerated the deposition of suberin polyphenolic and lignin at the wound sites of potato tubers with the formation of thicker cell layers. This occurred with increased localized activities of key enzymes in the suberin polyphenolic and lignin pathways, including phenylalanine ammonia lyase, 4-coumaryl-coenzyme A ligase, cinnamyl alcohol dehydrogenase and peroxidase (33.90–64.32%), as well as the contents of cinnamic acid, sinapic acid, flavonoids, lignins and total phenolics (19.70–23.46%) in the wounded sites of potato tubers on day 7 after wounding. Our results indicated that foliar application of chitosan accelerated wound-induced suberization of potato tubers and could mitigate post-harvest product damages