Effective Interventions on Word-Problem-Solving for Students with Mathematics Difficulties

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Early Termination In Partition Search for Encoding

An efficient partition search termination strategy suitable for high-quality encoding is proposed, which largely speeds up the encoder without sacrificing the quality. This is achieved using a partition search system. The partition search system constructs a partition search tree of an NxN encoding unit comprising multiple partition nodes to conduct a partition search. The system evaluates a partition node from the multiple partition nodes of the partition search tree. After a partition node is evaluated, the early termination checking is conducted by the system based on the information gathered during the partition evaluation. If the early termination criteria are met, the current partition size is decided as the final best choice, and all its child nodes are not searched and are removed from the search tree. Consequently, the system terminates the partition search in the current branch. However, if the early termination criteria are not met, the system goes back to evaluating the next partition node from the multiple partition nodes of the partition search tree until the early termination criteria is met or all nodes are checked

Essays on Real Estate Investment Trusts

The first essay of this dissertation investigates the relationship between downside risk and returns of real estate investment trusts (REITs) and assesses the performance of real estate mutual funds (REMFs). We measure the asymmetric risk through downside and upside betas and through the measures incorporated higher moments such as coskewness and Leland\u27s beta. We do not find significant contemporary relationship between the asymmetric risk and returns of REITs. There are only a small portion of REITs reacting to up and down market conditions differently. We find weak evidence that this asymmetric movement of REITs to market may be due to small and value components embedded in REITs. We evaluate the performance of real estate mutual funds (REMFs) from the asymmetric risk perception. According to our results, most of REMFs do not outperform the market. The downside risk helps to explain some of the abnormal returns associated with REMFs. However, the evaluation may be sensitive to the choices of the model and the market index being used. The second essay examines the liquidity of Asian REITs. We use various measures to assess the liquidity of JREITs and SREITs. The overall evidence indicates that the liquidity of JREITs is greater than that of SREITs. Comparing to non-REIT stocks, JREITs are less liquid than Japanese common stocks while there is no significant difference in liquidity between SREITs and Singaporean common stocks. There is also strong evidence that US REITs have smaller spreads and are traded more often than both JREITs and SREITs. We also find that the primary determinants of JREIT spreads are turnover and return volatility. The secondary factors that affect the spread of JREITs are life and property holdings. The dominant factors affecting SREITs\u27 spreads are price, return volatility, and life. The significance of life suggests that there is a learning effect existed in both JREIT and SREIT markets in 2005

Spatial variation of catchment-oriented extreme rainfall in England and Wales

This paper presents the spatial variation of the annual maximum daily rainfall (AMDR) in more than 900 catchments of England and Wales over the last century with respect to different spatial features including geographic location, elevation, size, orientation and shape of catchments. A SPER toolbox is employed to extract the spatial features of catchments where the AMDR is modelled by a well-tested Generalized Extreme Value (GEV) distribution. The results show that the GEV parameters μ and σ exhibit similar patterns and are usually larger with higher elevations. Increasing catchment size can decrease parameters due to areal averaging, however, in the middle-sized transition regions of the rainfall variation, e.g., east Wales, the trend reverses. For areas at high elevation, parameters are greater in the west-northwest-oriented catchments while parameters in west-northwest or east-northeast-oriented catchments at lower elevation are similar or smaller than those with a north-south orientation. An elongated shape catchment usually has smaller parameters than a rounded shape one. These findings reveal the heterogeneity of extreme rainfall distribution in space with respect to different spatial characteristics of catchments even under the same climate, which lays a basis for further catchment-based analysis concerning the relationship between hydrological response and geomorphic properties

A Flood Risk Framework Capturing the Seasonality of and Dependence Between Rainfall and Sea Levels—An Application to Ho Chi Minh City, Vietnam

State-of-the-art flood hazard maps in coastal cities are often obtained from simulating coastal or pluvial events separately. This method does not account for the seasonality of flood drivers and their mutual dependence. In this article, we include the impact of these two factors in a computationally efficient probabilistic framework for flood risk calculation, using Ho Chi Minh City (HCMC) as a case study. HCMC can be flooded sub-annually by high tide, rainfall and storm surge events or a combination thereof during the monsoon or tropical cyclones. Using long gauge observations, we stochastically model 10,000 years of rainfall and sea level events based on their monthly distributions, dependence structure and co-occurrence rate. The impact from each stochastic event is then obtained from a damage function built from selected rainfall and sea level combinations, leading to an expected annual damage (EAD) of $1.02B (95th annual damage percentile of$2.15B). We find no dependence for most months and large differences in expected damage across months ($36M-166M) driven by the seasonality of rainfall and sea levels. Excluding monthly variability leads to a serious underestimation of the EAD by 72% to 83%. This is because high-probability flood events, which can happen multiple times during the year and are properly captured by our framework, contribute the most to the EAD. This application illustrates the potential of our framework and advocates for the inclusion of flood drivers’ dynamics in coastal risk assessments

Is Manager Gender Important in the Performance of Mutual Funds?

We investigate whether there are differences in characteristics and performance of mutual funds caused by the manager’s gender. Through examining a large sample of U.S. domestic equity mutual fund, we find some evidence that suggests female managers have a lower risk tolerance than males. This leads to the observation that females tend to hold a higher total number of assets (stocks) and fewer assets in their top 10 holdings than do male managers. We then analyze performance within funds over time in order to evaluate the impact of changes in management’s gender composition on funds’ performance. We find some evidence that the percentage of female managers managing a fund is negatively related to the fund’s performance over time

HALO: Haptic Alerts for Low-hanging Obstacles in White Cane Navigation

White canes give the visually impaired the freedom to travel independently in unknown environments, but they cannot warn the user of overhead hazards such as tree branches. This paper presents the development and evaluation of a device that provides haptic cues to warn a visually impaired user of low-hanging obstacles during white cane navigation. The Haptic Alerts for Low-hanging Obstacles (HALO) system is a portable and affordable attachment to traditional white canes. By pairing distance data acquired from an ultrasonic range sensor with vibration feedback delivered by an eccentric mass motor, the device aims to alert users of low-hanging obstacles without interfering with the standard functionality of a white cane. We conducted a preliminary validation study wherein twelve blindfolded subjects navigated a custom obstacle course with and without vibration alerts from HALO. The results showed that this new device is intuitive and highly effective at enabling the user to safely navigate around low-hanging obstacles

SERS Tags: Novel Optical Nanoprobes for Bioanalysis

CONTENTS1. Introduction1.1. Fundamental Theory of Surface-Enhanced Raman Scattering1.2. Optical Properties of SERS Tags2. Synthesis of SERS Tags2.1. Noble Metal Nanosubstrates2.1.1. Single Particle-Based SERS Substrates2.1.2. Nanoparticle Cluster-Based Substrates2.2. Raman Reporter Molecules2.2.1. Selection Principles and Reporter Types2.2.2. Self-Assembled Monolayer Coverage Strategy2.3. Surface Coating for Protection2.3.1. Biomolecule Coating2.3.2. Polymer Coating2.3.3. Liposome Coating2.3.4. Silica Coating2.4. Attachment of Targeting Molecules3. Bioanalysis Applications3.1. Ionic and Molecular Detection3.2. Pathogen Detection3.3. Live-Cell Imaging3.3.1. Cancer Marker Detection3.3.2. Intercellular Microenvironment Sensing3.4. Tissue SERS Imaging3.5. In Vivo SERS Imaging4. Challenges and Perspectives4.1. Reproducible Signal of SERS Tags4.1.1. Precisely Controlled Hot Spots for Nanosubstrates4.1.2. Calibration of SERS Intensities and Enhancements4.2. Improving Multiplexing Capability4.3. Reduced Size for Subcellular Imaging4.4. Development of Multifunctional Nanoplatforms4.4.1. Magnetic SERS Dots4.4.2. Multimodal Imaging Dots4.4.3. SERS Tag-Based Therapeutic Systems4.5. Biocompatibility5. Conclusions and Remarks</ul