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Animals living in extreme environments, such as hydrothermal vents, would be expected to have evolved protective shells or exoskeletons to maintain homeostasis. The outer part of the exoskeleton of vent crabs (Austinograea sp.) in the Indian Ocean hydrothermal vent was one of the hardest (approximately 7 GPa) biological materials ever reported. To explore the exoskeletal characteristics of vent crabs which enable them to adapt to severe environments, a comparative analysis was conducted with the Asian paddle crab (Charybdis japonica) living in coastal areas. Nanoindentation, thermogravimetric analysis, scanning electron microscopy, energy dispersive x-ray analysis, and Raman spectroscopy were used to analyze the mechanical properties, thermal stability, structure, surface components, and the composition of compounds, respectively. Though both species have four-layered exoskeletons, the outermost layer of the vent crab, a nano-granular structure, was much thicker than that of the coastal crab. The proportions of aluminum and sulfur that constitute the epicuticle of the exoskeleton were higher in the vent crab than in the coastal crab. There was a lack of water or volatile substances, lots of CaCO3, and no carotenoid-based compounds in the exoskeleton of the vent crab. These might have improved the mechanical properties and thermal stability of the hydrothermal species.

Tecchio et al. (J Neurophysiology 104: 1134–1140, 2010) reported that the application of anodal tDCS at primary motor cortex (M1) immediately after practice of a procedural motor skill enhanced consolidation, which in turn improved offline gain. Tecchio et al. noted, however, that this study did not account for known after-effects associated with this form of non-invasive stimulation. The present study was designed to explicitly reevaluate Tecchio et al.’s claim. As in the original study, individuals experienced either anodal or sham stimulation at M1 after practice of a serial reaction time task (SRTT) followed by test trials 15-min later. Two additional novel conditions experienced the test trials after 120-min rather than 15-min thus allowing potential stimulation after-effects to dissipate. The expectation was that if anodal stimulation influences post-practice consolidation leading to offline gain, this effect would be present not only at 15-min but also after 120-min. In agreement with the working hypothesis, findings revealed offline gain at both 15-min and the longer 2-h time period. Unexpectedly, we found no interaction between real and sham conditions. The lack of difference between Real and Sham effects weakens confidence in the potential of post-practice tDCS for consolidation enhancement, while it is more consistent with other claims that decoupling practice and anodal tDCS stimulation in time can reduce the effectiveness of exogenous stimulation for procedural skill gain.

Performing endurance flight for long-term missions, unmanned aerial vehicles (UAV) are safety–critical systems that requires high reliability. To achieve long flight time and high reliability altogether, S/W-based fault detection and isolation (FDI) methods are applied rather than H/W redundancy due to limitation of loading weight. This study focused on model-based FDI techniques against faults, difficult to sense via signal-based FDI methods. The existing observer-based and parameter identification-based methods have difficulties separating the faulty sensor from correlated fault sources or sensors that output the same type of measurements. In this study, the fault detection parameter was designed to detect a faulty sensor from correlated fault sources. The combination of the proposed method and the existing residual-based methods was also designed to separate the faulty sensor from other independent auxiliary sensors with same measurement variables. In addition, the optimal combination of the CUSUM test and technique using the fault detection parameter was designed for UAVs. The algorithm was installed on INS and verified via vehicle mounted test and captive flight test.

Thus far, the removal efficiency of non-point-pollution source removal facilities has been evaluated for individual rainfall events. However, as the removal efficiency for part of a single rainfall event has not been evaluated, adapting the removal facilities for these concentrations is imprecise. Of 18 rainfall events, the removal efficiency of a vortex-type facility as a BMP (Best Management Practice), a non-point-pollution source removal method, was assessed in this study in four assessment techniques and analyzed. In addition, the efficiency was assessed for the concentration using dynamic EMC (Event Mean Concentration). At a higher concentration, the efficiency becomes higher in terms of the TSS, COD, and TP results. In the case of TP, the concentration range of 0~2 mg/L showed the highest efficiency. In the case of Zn, low efficiency was shown in a concentration range of 0.2∼0.6 mg/L.

This article develops the analytical methods necessary to determine the prepayment patterns of a mortgage contract. The most obvious measure of how many years a mortgage is likely to last is the expected time to termination. It is this measure that we most fully explore. However, since the method employed is able to characterize the probability of prepayment in any given time period, the means is provided to determine any measure of the time to termination.

Recently there has been much research treating housing and other real assets as financial claims, primarily in order to value their derivative assets, such as mortgages and mortgage-backed securities. Real asset prices are then typically modeled as a lognormal process, in the same manner that has traditionally been applied to firm value. The service flow or implicit value of a house is thus considered, in analogy with stock dividends, to be a fixed proportion of the fluctuating house price. We consider the appropriateness of this formulation and draw some distinctions between real assets, such as a house, and investment enterprises, such as a firm. We then propose an alternative method of formulating the service flow and the price of real assets which seems more appropriate to the economic characteristic of such assets.

Taking advantage of recent developments in bargaining theory, we examine the bidding process for residential real estate. Within this game theoretic context, we consider whether the phenomenon of buyer's remorse is compatible with the rationality required of participants.