Towards Efficient SDRTV-to-HDRTV by Learning from Image Formation

Modern displays are capable of rendering video content with high dynamic range (HDR) and wide color gamut (WCG). However, the majority of available resources are still in standard dynamic range (SDR). As a result, there is significant value in transforming existing SDR content into the HDRTV standard. In this paper, we define and analyze the SDRTV-to-HDRTV task by modeling the formation of SDRTV/HDRTV content. Our analysis and observations indicate that a naive end-to-end supervised training pipeline suffers from severe gamut transition errors. To address this issue, we propose a novel three-step solution pipeline called HDRTVNet++, which includes adaptive global color mapping, local enhancement, and highlight refinement. The adaptive global color mapping step uses global statistics as guidance to perform image-adaptive color mapping. A local enhancement network is then deployed to enhance local details. Finally, we combine the two sub-networks above as a generator and achieve highlight consistency through GAN-based joint training. Our method is primarily designed for ultra-high-definition TV content and is therefore effective and lightweight for processing 4K resolution images. We also construct a dataset using HDR videos in the HDR10 standard, named HDRTV1K that contains 1235 and 117 training images and 117 testing images, all in 4K resolution. Besides, we select five metrics to evaluate the results of SDRTV-to-HDRTV algorithms. Our final results demonstrate state-of-the-art performance both quantitatively and visually. The code, model and dataset are available at https://github.com/xiaom233/HDRTVNet-plus.Comment: Extended version of HDRTVNe

Cassava genome from a wild ancestor to cultivated varieties

Cassava is a major tropical food crop in the Euphorbiaceae family that has high carbohydrate production potential and adaptability to diverse environments. Here we present the draft genome sequences of a wild ancestor and a domesticated variety of cassava and comparative analyses with a partial inbred line. We identify 1,584 and 1,678 gene models specific to the wild and domesticated varieties, respectively, and discover high heterozygosity and millions of single-nucleotide variations. Our analyses reveal that genes involved in photosynthesis, starch accumulation and abiotic stresses have been positively selected, whereas those involved in cell wall biosynthesis and secondary metabolism, including cyanogenic glucoside formation, have been negatively selected in the cultivated varieties, reflecting the result of natural selection and domestication. Differences in microRNA genes and retrotransposon regulation could partly explain an increased carbon flux towards starch accumulation and reduced cyanogenic glucoside accumulation in domesticated cassava. These results may contribute to genetic improvement of cassava through better understanding of its biology

The Development of Stylolites in Carbonate Formation: Implication for CO2 Sequestration

The impact of CO2 sequestration on the host formation is an issue occurring over geologic time. Laboratory tests can provide important results to investigate this matter but have limitations due to a relatively short timeline. Based on literature review and core sample observation, naturally occurred geological phenomena, stylolites are studied in this paper for understanding CO2 sequestration in deep carbonate formations. Stylolites are distinctive and pervasive structures in carbonates that are related to water‐assisted pressure solution. Pressure solution involving stylolitization is thought to be the main mechanism of compaction and cementation for many carbonates. In parallel, CO2 sequestration in carbonate formation involves extensive chemical reactions among water, CO2 and rock matrix, favoring chemical compaction as a consequence. An analogue between stylolites and CO2 sequestration induced formation heterogeneity exists in the sense of chemical compaction, as both pressure solution in stylolites and CO2 enriched solution in CO3 sequestration in carbonate formations may all introduce abnormal porous regions. The shear and/or tension fractures associated with stylolites zones may develop vertically or sub‐vertically; all these give us alert for long‐term safety of CO2 sequestration. Thus a study of stylolites will help to understand the CO2 sequestration in deep carbonate formation in the long run

Analysis of bullwhip effect and inventory cost in the online closed-loop supply chain

This paper focuses on the impact of return decisions on the bullwhip effect in the online closed-loop supply chain. We investigate the optimal return modes when the inspection system is undertaken by the logistics centre or the remanufacturer. Then, we optimise the online retailers’ return decisions of minimising the inventory cost and bullwhip effect under different supply chain circumstances. Distinctive from previous conclusion that the inspection operation is usually undertaken by the remanufacturer to sort the returned products, the analysis results reveal that the optimal decision of mitigating the bullwhip effect in most cases is to set the inspection system on logistics centre. Besides, consumers’ return and exchange behaviours in e-commerce have different impacts on the supply chain efficiency. The product return can not necessarily mitigate the information distortion in online closed-loop supply chain. The research provides insights for managers to strategise about return policies and resource allocation in different e-commerce contexts

In Situ pH Monitoring in Turbid Coastal Waters Based on Self-Electrodeposition Ir/IrO2 Electrode

Direct and accurate monitoring of pH in turbid waters is a challenging task for environmental monitoring and analysis. In this study, iridium oxide (IrO2) with selective sensing ability toward H+ was produced on the surface of iridium (Ir) electrode by rapid self-electrodeposition. IrO2 was deposited on electrode surface by atomic force, which could decrease the adverse effect of the suspended particles in turbid water. Properties of the Ir/IrO2 electrode were investigated by X-ray photoelectron spectroscopy, scanning electron microscopy, and electrochemical technology. The sensitivity and response time of the Ir/IrO2 electrode for pH determination were assessed, and a rapid and linear pH response of approximately 65 +/- 3.5 mV pH(-1) was observed across a wide pH range between 1.8 and 11.9. Moreover, the electrode exhibited a good temperature linearity (20 degrees C-60 degrees C), low potential drift (0.75 mV h(-1)), high accuracy (+/- 0.05), and a long life span (up to 30 d). The practical investigation revealed faster equilibrium rate and higher stability of the Ir/IrO2 electrode than that of traditional glass pH electrode. Furthermore, the Ir/IrO2 electrode was successfully used for in situ pH monitoring in 750 formazin turbidity units (FTU) for turbid coastal river water. Therefore, the developed Ir/IrO2 pH electrode offers large applicability for in situ pH monitoring in turbid environmental water matrices

Application of New Modified Genetic Algorithm in Inverse Calculation of Strong Source Location

With the rapid development of intelligent systems, the application of genetic algorithms to quickly and accurately determine the location of hazardous gas leaks is of great practical significance. To further improve the convergence efficiency and stability of the inverse calculation, a new improved genetic algorithm (NMGA) is designed on the basis of the improved genetic algorithm (MGA). The adaptive crossover rate and mutation rate change with the evolution algebra to guide the development trend of good gene genetics and change the genetic crossover ratio of parents and children in the culler’s gene pool to avoid damaging the good group genes by introducing bad genes. This study modified the adaptive crossover rate and mutation rate that change with the evolutionary generations to guide the development of good gene inheritance. Meanwhile, this study changed the genetic crossover ratio of parent and offspring in the elimination gene pool to avoid the introduction of unfavorable genes and the destruction of excellent group genes. Through the calculation simulation of the new improved genetic algorithm (NMGA) in Matlab and the quantitative and qualitative comparative analysis with the MGA statistical results, it is shown that NMGA can improve the slow convergence speed of MGA by reducing the number of iterations on the premise of ensuring the stability of MGA and the accuracy of the inverse calculation. The results indicated that the convergence rate and stability of NMGA greatly improved its convergence efficiency, inverse calculation accuracy, and stability, thereby providing powerful decision-making data for rapid emergency rescue work for sudden light gas leakage accidents