Application of a neuro-fuzzy model to landslide-susceptibility mapping for shallow landslides in a tropical hilly area.

This paper presents landslide-susceptibility mapping using an adaptive neuro-fuzzy inference system (ANFIS) using a geographic information system (GIS) environment. In the first stage, landslide locations from the study area were identified by interpreting aerial photographs and supported by an extensive field survey. In the second stage, landslide-related conditioning factors such as altitude, slope angle, plan curvature, distance to drainage, distance to road, soil texture and stream power index (SPI) were extracted from the topographic and soil maps. Then, landslide-susceptible areas were analyzed by the ANFIS approach and mapped using landslide-conditioning factors. In particular, various membership functions (MFs) were applied for the landslide-susceptibility mapping and their results were compared with the field-verified landslide locations. Additionally, the receiver operating characteristics (ROC) curve for all landslide susceptibility maps were drawn and the areas under curve values were calculated. The ROC curve technique is based on the plotting of model sensitivity — true positive fraction values calculated for different threshold values, versus model specificity — true negative fraction values, on a graph. Landslide test locations that were not used during the ANFIS modeling purpose were used to validate the landslide susceptibility maps. The validation results revealed that the susceptibility maps constructed by the ANFIS predictive models using triangular, trapezoidal, generalized bell and polynomial MFs produced reasonable results (84.39%), which can be used for preliminary land-use planning. Finally, the authors concluded that ANFIS is a very useful and an effective tool in regional landslide susceptibility assessment

Debt Maturity And Investment Efficiency Evidence From Korea

This study empirically analyzes the effect of debt maturity on investment efficiency, which is measured by using McNichols and Stubben (2008). Debt maturity is measured using current debt ratio and dummy variable. Specifically, we will investigate how short-term debt affects investment efficiency. Additionally, we will investigate the relation between the short-term debt affects investment efficiency according to debt maturity group. The results of this study are as follows. First, the short-term debt and investment efficiency were significantly positive (+) in both the total sample and the over-investment sample. Second, as a result of analyzing the maturity of debt by group according to the current debt ratio, the relationship between earnings quality and investment efficiency was significantly positive (+) in the short-term debt group. it is suggested that debt maturity and investment efficiency can be different for the total sample, over-investment sample, under-investment sample, and the relationship between earnings quality and investment efficiency can be differentiated by debt maturity group. This study has following additional contributions in comparison with domestic prior studies related to investment efficiency. First, prior studies related to investment efficiency are mainly concerned with the quality of financial reporting. This study implies that the relationship between investment efficiency and quality of financial reporting, and the relationship between debt maturity and investment efficiency among the characteristics of debt. Second, from the results of the analysis of the debt maturity and investment efficiency, it is confirmed that the debt is operating as a mechanism to monitor the investment efficiency of the corporation. Third, the analysis of debt maturity group suggests that the relationship between earnings quality and investment efficiency may be differentiated by short and long debt levels during debt financing. The limitations of this study are as follows. First, we might have not considered omitted other variables. Second, we might not have fully considered other proxies for the characteristics of the debt maturity and investment efficiency. Third, there may be a measurement error in the quality of earnings and investment efficiency. Finally, the relationship between debt maturity and investment efficiency can vary depending on the circumstances of the company. For example, specific debt contract provisions or national regulatory environment. Therefore, attention should be paid to the generalization of the results of this study

Does Board Characteristics Constrain Real Earnings Management? Evidence From Korea

This study empirically analyzes the effect of board characteristics on real earnings management, which is measured by using three proxies including abnormal cash flows from operations, abnormal discretionary expenses, and abnormal production costs. Specifically, we will investigate how board independence (or board size) affects real earnings management. Additionally, we will investigate the relation between the board characteristics and real earnings management according to before K-IFRS mandatory adoption or after K-IFRS mandatory adoption. The empirical results of this study are as follows. First, the relation between board independence (board size) and the absolute value of abnormal cash flows from operations is statistically significant and positive (+). Second, the relation between board independence (board size) and the absolute value of abnormal production costs is statistically significant and positive (+). Third, the relation between board independence (board size) and the absolute value of abnormal discretionary expenses is statistically significant and positive (+). These findings present that the board independence (or board size) does not constrain real earnings management. Thus, these mean that board independence (or board size) does not work as a mechanism to reduce real earnings management. This study contributes to accounting research as it directly tests the relation between the board characteristics and real earnings management in Korea, providing empirical support that a board independence (board size) does not constrain real earnings management as effectively as it constrains accrual earnings management.&nbsp

Personalized Cinemagraphs using Semantic Understanding and Collaborative Learning

Cinemagraphs are a compelling way to convey dynamic aspects of a scene. In these media, dynamic and still elements are juxtaposed to create an artistic and narrative experience. Creating a high-quality, aesthetically pleasing cinemagraph requires isolating objects in a semantically meaningful way and then selecting good start times and looping periods for those objects to minimize visual artifacts (such a tearing). To achieve this, we present a new technique that uses object recognition and semantic segmentation as part of an optimization method to automatically create cinemagraphs from videos that are both visually appealing and semantically meaningful. Given a scene with multiple objects, there are many cinemagraphs one could create. Our method evaluates these multiple candidates and presents the best one, as determined by a model trained to predict human preferences in a collaborative way. We demonstrate the effectiveness of our approach with multiple results and a user study.Comment: To appear in ICCV 2017. Total 17 pages including the supplementary materia

Frequency limits of sequential readout for sensing AC magnetic fields using nitrogen-vacancy centers in diamond

The nitrogen-vacancy (NV) centers in diamond have ability to sense alternating-current (AC) magnetic fields with high spatial resolution. However, the frequency range of AC sensing protocols based on dynamical decoupling (DD) sequences has not been thoroughly explored experimentally. In this work, we aimed to determine the sensitivity of ac magnetic field as a function of frequency using sequential readout method. The upper limit at high frequency is clearly determined by Rabi frequency, in line with the expected effect of finite DD-pulse width. In contrast, the lower frequency limit is primarily governed by the duration of optical repolarization rather than the decoherence time (T$_2$) of NV spins. This becomes particularly crucial when the repetition (dwell) time of the sequential readout is fixed to maintain the acquisition bandwidth. The equation we provide successfully describes the tendency in the frequency dependence. In addition, at the near-optimal frequency of 1 MHz, we reached a maximum sensitivity of 229 pT/$\sqrt{\mathrm{Hz}}$ by employing the XY4-(4) DD sequence.Comment: 7 pages, 5 figure

3-D finite element analysis of the effects of post location and loading location on stress distribution in root canals of the mandibular 1st molar

Objective The purpose of this study was to evaluate, by using finite element analysis, the influence of post location and occlusal loading location on the stress distribution pattern inside the root canals of the mandibular 1st molar. Material and Methods Three different 3-D models of the mandibular 1st molar were established: no post (NP) – a model of endodontic and prosthodontic treatments; mesiobuccal post (MP) – a model of endodontic and prosthodontic treatments with a post in the mesiobuccal canal; and distal post (DP) – a model of endodontic and prosthodontic treatments with a post in the distal canal. A vertical force of 300 N, perpendicular to the occlusal plane, was applied to one of five 1 mm2 areas on the occlusal surface; mesial marginal ridge, distal marginal ridge, mesiobuccal cusp, distobuccal cusp, and central fossa. Finite element analysis was used to calculate the equivalent von Mises stresses on each root canal. Results The DP model showed similar maximum stress values to the NP model, while the MP model showed markedly greater maximum stress values. The post procedure increased stress concentration inside the canals, although this was significantly affected by the site of the force. Conclusions In the mandibular 1st molar, the distal canal is the better place to insert the post than the mesiobuccal canal. However, if insertion into the mesiobuccal canal is unavoidable, there should be consideration on the occlusal contact, making central fossa and distal marginal ridge the main functioning areas

Corneal cell viability and structure after transcorneal freezing–thawing in the human cornea

Purpose: Although cryotherapy has long been used to eradicate corneal lesions, there have been no reports of adverse effects of cryotherapy on human corneas. We performed this study to evaluate and characterize ultrastructural damage to the human cornea following the transcorneal freezing-and-thawing procedure. Methods: Seven human donor corneas were randomly divided into three groups. 1, 2, and 3 repetitive freezing-and-thawing procedures were respectively applied to donor corneas in each group. A cryoprobe was cooled to-80°C, and placed on the anterior surface 1.5 mm central to the limbus for 3 seconds. Samples were then allowed to spontaneously defrost. A cornea without the treatment was used as a control. Samples were evaluated through hematoxylin & eosin staining, TUNEL assay, and electron microscopy. Results: After transcorneal cryoinjury, it was observed that corneal endothelial cells were lost and Descemet's membrane was denuded where the cryoprobe was applied. Corneal stromal cells were damaged, and the damage was more marked in the posterior stroma. The extent of damage increased with an increasing number of freezing-thawing repetitions. In contrast, corneal epithelial cells showed no cryo-induced damage, and Bowman's layer remained intact in all groups. Conclusions: The susceptibility to transcorneal cryo-injury differed among the corneal layers; the corneal endothelium was most susceptible, and the epithelium was least susceptible. Caution would thus be advised in regard to the potential damage in corneal endothelium when treating patients with corneal lesions using transcorneal cryotherapy.©2010 Oh et al, publisher and licensee Dove Medical Press Ltd.Y