This study examines whether institutional ownership and analyst following affect the value relevance of disclosed versus recognized pension liabilities. Using a sample of firms with pension ...liabilities that were disclosed under SFAS No. 87 and subsequently recognized under SFAS No. 158 from 1999 to 2007, I find that off-balance-sheet pension liabilities are more value relevant for firms with a higher level of institutional ownership or analyst following in the pre-158 period. More importantly, I find that SFAS No. 158 increases the value relevance of previously disclosed off-balance-sheet pension liabilities for firms with a low level of institutional ownership or analyst following, and that the increase in the value relevance becomes less pronounced for firms with a higher level of institutional ownership or analyst following. Overall, the results are consistent with the view that institutional ownership and analyst following affect the value relevance of disclosed information as well as the valuation difference between disclosed and recognized information. This study also highlights the importance of considering institutional ownership and analyst following in the value-relevance research.
Metal–organic frameworks (MOFs), constructed from organic linkers and inorganic building blocks, are well-known for their high crystallinity, high surface areas, and high component tunability. The ...stability of MOFs is a key prerequisite for their potential practical applications in areas including storage, separation, catalysis, and biomedicine since it is essential to guarantee the framework integrity during utilization. However, MOFs are prone to destruction under external stimuli, considerably hampering their commercialization. In this Review, we provide an overview of the situations where MOFs undergo destruction due to external stimuli such as chemical, thermal, photolytic, radiolytic, electronic, and mechanical factors and offer guidelines to avoid unwanted degradation happened to the framework. Furthermore, we discuss possible destruction mechanisms and their varying derived products. In particular, we highlight cases that utilize MOF instability to fabricate varying materials including hierarchically porous MOFs, monolayer MOF nanosheets, amorphous MOF liquids and glasses, polymers, metal nanoparticles, metal carbide nanoparticles, and carbon materials. Finally, we provide a perspective on the utilization of MOF destruction to develop advanced materials with a superior hierarchy for various applications.
In recent years, the rapid development of modern society is calling for advanced energy storage to meet the growing demands of energy supply and generation. As one of the most promising energy ...storage systems, secondary batteries are attracting much attention. The electrolyte is an important part of the secondary battery, and its composition is closely related to the electrochemical performance of the secondary batteries. Lithium‐ion battery electrolyte is mainly composed of solvents, additives, and lithium salts, which are prepared according to specific proportions under certain conditions and according to the needs of characteristics. This review analyzes the advantages and current problems of the liquid electrolytes in lithium‐ion batteries (LIBs) from the mechanism of action and failure mechanism, summarizes the research progress of solvents, lithium salts, and additives, analyzes the future trends and requirements of lithium‐ion battery electrolytes, and points out the emerging opportunities in advanced lithium‐ion battery electrolytes development.
This review analyzes the advantages and current problems of the liquid electrolytes in lithium‐ion batteries from the mechanism of action and failure mechanism, summarizes the research progress of solvents, lithium salts, and additives, analyzes the future trends and requirements of lithium‐ion battery electrolytes, and points out the emerging opportunities in advanced lithium‐ion battery electrolytes development.
As one of the most important smart materials, fluorescent hydrogel actuators can produce both color and shape changes under external stimuli. In the present work, an effective approach to develop a ...novel fluorescent hydrogel actuator with pH and thermo dual responsiveness is proposed. Through incorporating pH‐responsive perylene tetracarboxylic acid (PTCA), which is a typical fluorescent moiety with aggregation‐caused quenching (ACQ) effect, into an anisotropic poly(N‐isopropylacrylamide)–polyacrylamide (PNIPAm‐PAAm) structure, the obtained hydrogel exhibits stable thermoresponsive shape deformation and switchable fluorescence performance upon a pH trigger. Therefore, fluorescence‐quenching‐based and actuation‐based information can be revealed when exposed to UV light and immersed into warm water, respectively. Moreover, the thermoresponsive actuating behavior can be applied to further hide the fluorescence‐quenching‐based images. The present work may provide new insights into the design and preparation of novel stimuli‐responsive hydrogel actuators.
A novel fluorescent hydrogel with Janus structure is fabricated. The hydrogel exhibits pH‐responsive fluorescence and thermally induced actuating behaviors, which may provide new insights into the design and fabrication of novel intelligent materials.
Given a reference color image and a destination grayscale image, this paper presents a novel automatic colorization algorithm that transfers color information from the reference image to the ...destination image. Since the reference and destination images may contain content at different or even varying scales (due to changes of distance between objects and the camera), existing texture matching-based methods can often perform poorly. We propose a novel cross-scale texture matching method to improve the robustness and quality of the colorization results. Suitable matching scales are considered locally, which are then fused using global optimization that minimizes both the matching errors and spatial change of scales. The minimization is efficiently solved using a multi-label graph-cut algorithm. Since only low-level texture features are used, texture matching-based colorization can still produce semantically incorrect results, such as meadow appearing above the sky. We consider a class of semantic violation where the statistics of up-down relationships learned from the reference image are violated and propose an effective method to identify and correct unreasonable colorization. Finally, a novel nonlocal ℓ 1 optimization framework is developed to propagate high confidence micro-scribbles to regions of lower confidence to produce a fully colorized image. Qualitative and quantitative evaluations show that our method outperforms several state-of-the-art methods.
Arranging ionic liquids (ILs) with long‐range order can not only enhance their performance in a desired application, but can also help elucidate the vital between structure and properties. However, ...this is still a challenge and no example has been reported to date. Herein, we report a feasible strategy to achieve a crystalline IL via coordination self‐assembly based reticular chemistry. IL1MOF, was prepared by designing an IL bridging ligand and then connecting them with metal clusters. IL1MOF has a unique structure, where the IL ligands are arranged on a long‐range ordered framework but have a labile ionic center. This structure enables IL1MOF to break through the typical limitation where the solid ILs have lower proton conductivity than their counterpart bulk ILs. IL1MOF shows 2–4 orders of magnitude higher proton conductivity than its counterpart IL monomer across a wide temperature range. Moreover, by confining the IL within ultramicropores (<1 nm), IL1MOF suppresses the liquid–solid phase transition temperatures to lower than −150 °C, allowing it to function with high conductivity in a subzero temperature range.
A reticular chemistry based strategy opens a facile toolbox for designing liquid molecules with long‐rang‐ordered framework of MOF. IL1MOF is the first crystalline ionic liquid (IL) combining a balance of good mechanical properties and high conductivity. It expands the use of IL electrolytes to an low temperature region.
Human pose transfer, which aims at transferring the appearance of a given person to a target pose, is very challenging and important in many applications. Previous work ignores the guidance of pose ...features or only uses local attention mechanism, leading to implausible and blurry results. We propose a new human pose transfer method using a generative adversarial network (GAN) with simplified cascaded blocks. In each block, we propose a pose-guided non-local attention (PoNA) mechanism with a long-range dependency scheme to select more important regions of image features to transfer. We also design pre-posed image-guided pose feature update and post-posed pose-guided image feature update to better utilize the pose and image features. Our network is simple, stable, and easy to train. Quantitative and qualitative results on Market-1501 and DeepFashion datasets show the efficacy and efficiency of our model. Compared with state-of-the-art methods, our model generates sharper and more realistic images with rich details, while having fewer parameters and faster speed. Furthermore, our generated images can help to alleviate data insufficiency for person re-identification.
This article proposes a novel periodic event-triggered terminal sliding mode speed regulation scheme for the networked permanent-magnet synchronous motor (PMSM). The novel speed regulation strategy ...combines advantages of both terminal sliding mode control (TSMC) and periodic event-triggered mechanism. The satisfied speed regulation performance can be guaranteed by using TSMC to compensate the external disturbances and parameter uncertainties. The communication burden between the central controller and the remote motor is reduced by the periodic event-triggered protocol. To reduce the chattering in the TSMC signal, an extended state observer (ESO) is further introduced to estimate all possible perturbations, in which the upper bound of the estimation error is analyzed explicitly. Then, a binary-based genetic algorithm (GA) is adopted to find the optimal observer parameters. A key challenge here is how to estimate the actual bound of the triggering error under the periodic event-triggered mechanism. To this end, an explicit selection criterion of the periodic sampling period is developed by utilizing the known constrained information of the PMSM. It is proven that the proposed novel periodic event-triggered TSMC with a proper selection of the control gain can guarantee the reachability of the sliding region and the ultimate boundedness of the regulation errors simultaneously. Finally, the effectiveness of the proposed novel periodic event-triggered TSMC via a GA-optimized ESO is demonstrated in both simulation and experiment results for a real PMSM platform.
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