To overcome the lithium storage barriers of current lithium-ion batteries, it is imperative that conventional low capacity graphite anodes be replaced with other higher capacity anode materials. Silicon is a promising alternative anode material due to its huge energy densities; however, its lithiumconcentration-dependent volumetric changes can induce severely adverse effects that lead to drastic degradations in capacity during cycling. The dealloying of Si-metal alloys is recently suggested as a scalable approach to fabricate high-performance porous Si anode materials. Herein, a microstructure controlled porous Si is developed by the dealloying in conjunction with wet alkaline chemical etching. The resulting 3D networked structure enables enhancement in lithium storage properties when the Si-based material is applied not only as a single active material but also in a graphite-blended electrode.

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The purpose of this report is to review the evidence on the profitability of technical analysis. To achieve this purpose, the report comprehensively reviews survey, theoretical and empirical studies regarding technical trading strategies. We begin by overviewing survey studies that have directly investigated market participants' experience and views on technical analysis. The survey literature indicates that technical analysis has been widely used by market participants in futures markets and foreign exchange markets, and that about 30% to 40% of practitioners appear to believe that technical analysis is an important factor in determining price movement at shorter time horizons up to 6 months. Then we provide an overview of theoretical models that include implications about the profitability of technical analysis. Conventional efficient market theories, such as the martingale model and random walk models, rule out the possibility of technical trading profits in speculative markets, while relatively recent models such as noisy rational expectation models or behavioral models suggest that technical trading strategies may be profitable due to noise in the market or investors' irrational behavior. Finally, empirical studies are surveyed. In this report, the empirical literature is categorized into two groups, "early" and "modern" studies, according to the characteristics of testing procedures.Early studies indicated that technical trading strategies were profitable in foreign exchange markets and futures markets, but not in stock markets before the 1980s. Modern studies indicated that technical trading strategies consistently generated economic profits in a variety of speculative markets at least until the early 1990s. Among a total of 92 modern studies, 58 studies found positive results regarding technical trading strategies, while 24 studies obtained negative results. Ten studies indicated mixed results. Despite the positive evidence on the profitability of technical trading strategies, it appears that most empirical studies are subject to various problems in their testing procedures, e.g., data snooping, ex post selection of trading rules or search technologies, and difficulties in estimation of risk and transaction costs. Future research must address these deficiencies in testing in order to provide conclusive evidence on the profitability of technical trading strategies.ii

Real time dilation behaviors of a Si-Ti-Fe-Al alloy electrode adopting a poly (amide-imide) binder were investigated to understand the effects of thermal treatment temperature for PAI binder on the electrochemical performance of the Si-alloy electrode using an in-situ electrochemical dilatometer. In situ measurement of the electrode thickness showed that the changes in the volume of the Si electrode was suppressed by heat treatment greater than 300 C, which well agreed with the improved cycle performance of the Sialloy electrode thermally treated at the same temperature. Differential dilation plots of the Si-alloy electrodes were found to reveal more detailed changes in the volume of the Si-alloy electrode, thus showing that the enhanced mechanical strength of thermally treated PAI effectively could control the expansion and contraction of the Si-alloy electrode and ensuring a more stable cycle performance of the Si-alloy electrode.

Long-term treatment with systemic steroids and SLE may increase the risk of spontaneous rupture of an unscarred uterus.