Reversible Data Hiding Using Prediction-based Adaptive Embedding

[[abstract]]In this paper, we propose a new algorithm in reversible data hiding with prediction-based scheme. Reversible data hiding can be implemented with two types, one is by modifying the histogram of images, named the histogram-based scheme, and the other is by changing the difference value between neighboring pixels, called the difference-expansion-based (DE-based) method. Considering the ease of implementation, we employ the histogram-based scheme as the base, integrated with the DE-based methods, which is famous for the abundance in embedding capacity, in our algorithm. For hiding the secret information, the differences between original and predicted images are produced firstly, and they are intentionally altered to make reversible data hiding possible. By utilizing the advantages from the two types of methods, by change of histograms of difference values, global and local characteristics of original images can be utilized for hiding more capacity with acceptable quality of output image. With our method, it performs better in embedding capacity, image quality, and side information than conventional algorithm in literature. It also has the potential for the integration to relating algorithms for practical applications.[[sponsorship]]Korea Information Processing Society (KIPS)[[incitationindex]]EI[[conferencetype]]國際[[conferencedate]]20121220~20121222[[booktype]]紙本[[iscallforpapers]]Y[[conferencelocation]]Hong Kon

ANALYSES OF MULTIVITAMINS IN NUTRACEUTICALS BY REVERSE PHASE HPLC WITH DAD, ELSD AND MS

ABSTRACT Vitamins are essential to human beings and support long-term healthy lifestyle. They exist widely in food, but in small amount. Hence, dietary supplements and fortified food products are more and more popular in the nutritional markets. According to the Infant Formula Act of 1980, the range of each of the nutrients should fall within a specific range or above the required minimum, so there is an increasing interest of accurate measurement of vitamins, particularly the B-group vitamins. However, traditional methods for vitamin B analyses are time-consuming and often in poor accuracy. As a result, rapid and reliable analytical methods for simultaneous determination of water-soluble vitamins in multivitamin and supplemented foods are important, indispensible and needed by food and nutraceutical industries for quality control during production, and for accurate evaluation of data and label clams. Due to low concentrations of B8 and B9 in nature, there is a critical need for preconcentration to facilitate their isolation and purification from a complex matrix like food. In order to minimize the consumption of solvents, solid phase extraction (SPE) has been introduced for sample preparation. In this study, two types of SPE, i.e., reversed-phase C18 and strong anion-exchange phase, were used for sample clean-up and pre-concentration. The average recoveries for vitamin B3, B5, B7 and B9 were 101.3%, 102.9%, 92.8% and 102.6%, respectively, by using C18 SPE. In contrast, the strong anion-exchange SPE provided the average recoveries of B3, B5, B7 and B9 in 91.5%, 93.0%, 109.1% and 106.7%, respectively. Furthermore, simultaneous determination of water-soluble vitamins was developed by a HPLC system installed with a ZORBAX Eclipse XDB-C18 (250mm x 4.6mm, 5 μm particle size, Aglient Technologies, Inc., Loveland, CO, USA) with a guard column (12.5mm x 4.6mm, 5 μm particle size), and compared by three detectors, including DAD, ELSD and MS. The B-complex supplement, multivitamin/multimineral tablets and powder and vitamin drink were tested to verify HPLC method. According to the results, LC-MS is the best to do the simultaneous determination of the B-group vitamins in lights of its analytical accuracy, precision, sensitivity and versatility

On the detectability of multiple input multiple output (MIMO) radar signals using conventional electronic warfare support (ES) receivers

A research report submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science in Engineering. Johannesburg, 2016Multiple-Input Multiple-Output (MIMO) radar is a more general form of phased array radar, where each antenna in the array transmits linearly independent or mutually orthogonal signals. Sustained growth in computational power as well as the decline in the cost of integrated radio frequency (RF) components has made MIMO more viable than in the past. The potential emergence of practical MIMO radar has prompted an investigation into the detectability of MIMO radar signals using existing conventional Electronic warfare Support (ES) receivers such as the Crystal Video Receiver (CVR) and a specific type of superheterodyne receiver (superhet) known as the Zero IF Receiver (ZIFR). Literature on the detectability of MIMO radar signals is extremely scarce and this investigation aims to offer insights into the detectability of MIMO radar signals by means of computer simulations. The fundamental theory necessary for this research includes phased array radar theory, MIMO array radar theory and ES receiver signal detection theory. The detection of MIMO radar signals is compared to a reference phased array case to provide relative context. This investigation focusses on co-located Uniform Linear Arrays (ULA) based radar systems. The result of interest is the relative Signal-to-Noise Ratio (SNR) at which each type of radar can be detected by the ES receiver. Therefore, a lossless transmission, without loss of generality, is assumed. Constraints such as the equal transmit power over all antenna elements in the arrays, are used for a fair comparison. Many different array simulation setups are simulated. These setups are achieved by varying the number of elements in the array and the inter-element spacing. The phased array radar transmitted complex linear chirp signals, and the MIMO radar transmitted Hadamard sequences, interpolated using a Constant Envelope Linear-Route-of-Unity (CE-LRU) technique. The CVR and ZIFR detection thresholds were determined for a Probability of False Alarm (PFA) of 10-4. For all of the setups, the phased array radar was found to be more detectable than the MIMO radar at values of Probability of Detection (PD) below 0.6. The in phase coherent combination of phased array radar signals in its main beam resulted in a signal gain caused by the constructive addition of the signals. This gain thus increases with the number of antenna elements. In contrast, the MIMO signals also add coherently, but the instantaneous phase for each signal is a function of the transmitted signal as well as the direction of propagation relative to the array face. The set of orthogonal signals thus add constructively and destructively, resulting in the average signal power remaining approximately constant despite the number of antenna elements increasing. The difference in detectability of the phased array radar over MIMO radar therefore increases as the number of antenna elements is increased, due to the fact that each element is constrained to transmit a fixed power. Comparing the performance of the ZIFR and CVR, the ZIFR outperforms the CVR. This is due to the fact that the ZIFR implements a quadrature ES receiver, and was able to detect both types of radar signals at a lower SNR than the CVR. However, both ES receivers struggle to detect MIMO radar signals in comparison to detecting phased array radar signals and this performance margin widens as the number of transmitting elements is increased. This result suggests that research into dedicated techniques for the detection of MIMO radar signals using ES receivers may be necessary should the need arise to detect MIMO radar signals in future. This is the first quantitative analysis of the detectability of MIMO radar signals using conventional ES receivers that the author is aware of.MT201

Three Essays on Applied Environmental Economics.

This dissertation studies economic and ecological outcomes of large-scale weather risk and land-use change. Three independent studies are completed all of which apply microeconometric techniques, unique panel datasets, and, in two cases, fine-scale spatial data. Chapter 1 addresses the relationship among government agricultural programs, moral hazard, and land-use adaptation to weather risk. Using fine-scale spatial data, we identify farmers’ cropping pattern adaptation to weather risk, and whether a federal disaster assistance policy shock in 2008 from the Supplemental Revenue Assistance Payments (SURE) program distorts this adaptation. Our results show that farmers’ land-use decisions on corn, grassland, soybeans, and wheat are sensitive to pre-plant precipitation in North Dakota, but not in Iowa. Moreover, the SURE program gives farmers in North Dakota a disincentive to adjust cropping pattern to pre-plant precipitation. Limited adaptation implies substantial losses as climate change will increase the frequency of extreme weather events. Chapter 2 introduces microeconometric techniques into ecological research through its analysis of the effect of land-use change on grassland bird species richness. Using fine-scale weather, land cover, and soil data and dynamic panel data models, the causal impact of large-scale land-use change on grassland bird species richness is identified. Based on the estimation model, our projections show that that under the US biofuel mandate (our baseline scenario), the average grassland bird species richness in 2030 will decrease by 22% from 2013 levels. We also identify potential conservation hotspots by projecting heterogeneous county-level outcomes in a spatially-explicit setting under the baseline scenario. Chapter 3 assesses the economic impacts of extremely low Great Lakes water levels. We apply a difference-in-difference-in-differences estimator to generate causal evidence on the economic impacts of an episode of extremely low levels of Lakes Michigan and Huron in 2000-06. We find no evidence that economic outcomes were sensitive to extremely low lake levels. However, our statistically insignificant estimated results suggest that we cannot rule out substantial economic effects of the extremely low levels in the recreation and tourism sector.PHDNatural Resources and EnvironmentUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/120754/1/hsihuang_1.pd

Taiwan Internet Diffusion: An Empirical Study of Internet Interactive Effects

The primary objects of this research were applying the innovation diffusion model to internet hosts and internet subscribers . The results of this study may be a useful reference to the further concept building of the relationship of innovative and adopters