Selective Embedding Research Articles

Apps for life change: Critical review and solution directions

More and more users are using mobile apps to achieve changes in their lives related to their health. Given the complex task of accomplishing long-term behavioural change, developers have started to incorporate game elements into their apps as motivational tools and to increase user engagement. However, with increasing number of health-related apps available on mobile platforms every day, several issues have started to arise. In this paper, we critically review the health app landscape from several perspectives. We underline the current lack of scientific theory usage in app development, inefficient and selective embedding of gamification, low levels of personalization and potential privacy and trust issues in this domain. Given the multi-disciplinary nature of this set of problems, we propose integrated and user-centred frameworks as one potential solution direction to resolve problems both users and app-developers are facing today.

High receiver responsivity and low dark current of InP-based pin-photodiode array monolithically integrated with 90° hybrid and spot-size converter using selective embedding regrowth

High receiver responsivity and low dark current of InP-based pin-photodiode array monolithically integrated with 90° hybrid and spot-size converter using selective embedding regrowth

Reversible data hiding using Delaunay triangulation and selective embedment

In this paper, we propose a reversible data hiding method based on prediction and histogram-shifting (PHS) using Delaunay triangulation and selective embedment. Because the statistical properties of the prediction errors along the embedding direction are significantly altered due to the shifting operation, the existing PHS-based methods are vulnerable to some steganalyzers. The proposed method exploits a set of key-selected referential pixels to construct a 3D Delaunay mesh to obtain the prediction errors. The presence of the altered statistical properties along the embedding direction is unrevealed because the same set of prediction errors cannot be reconstructed. A selective embedment mechanism is used to control the embedding regions in the cover image for evading the detection of the steganalyzers based on low-amplitude stego signal. The experimental results reveal that the proposed method not only provides better payload and image quality than the existing PHS-based methods, but is also robust to the detection of modern steganalyzers such as histogram analysis and SPAM.

Robust image-adaptive watermarking using an adjustable dynamic strength factor

This paper presents a novel spread spectrum based image-adaptive watermarking technique where selective embedding of watermark has been done in small building blocks of the image, depending upon the respective entropies of the blocks. Novelty of this method lies in the flexibility of its strength factor which can be adjusted easily in order to obtain a required level of visual quality of the watermarked image in terms of PSNR. Easy adjustability of the strength factor has helped in experimentally demonstrating the inverse relationship between imperceptibility and robustness of the watermark. Positions of embedded blocks, means of low-frequency wavelet coefficients and size of watermark have been used as side information for decoding of the watermark. Applied technique has shown exceptional resistance to some of the common watermarking attacks such as JPEG compression, median filtering, Gaussian filtering and AWGN noise attacks.

A Tutorial for Audio Watermarking in the Cepstrum Domain

Embedding watermarks in an audio signal by considering the relation between the mean values of two consecutive groups of samples can lead to a faster and efficient audio watermarking algorithm. In this paper, we propose to divide the host audio signal into non-overlapping frames and then split the frames into two equal-sized sub-frames followed by cepstrum transformation of the samples of these sub-frames. Here, we individually calculate the mean values of the two sub-frames of each frame and change the values to embed watermarks. Depending on the watermark to embed (either 0 or 1), we interchange the mean value of the two sub-frames by selectively changing sample values. The technique of using consecutive sub-frames for selective embedding helps our algorithm to faster and easier determination of the value of the watermark bit. Therefore, our embedding technique and employment of cepstrum representation of samples together make the audio watermarking algorithm highly imperceptible and robust. Experimental results show that our new audio watermarking scheme is robust against various common signal processing attacks, such as amplitude modification, re-quantization, noise addition, resampling, MP3 conversion, etc.

Joint Access Point Selection and Local Discriminant Embedding for Energy Efficient and Accurate Wi-Fi Positioning

We propose a novel method for improving Wi-Fi positioning accuracy while reducing the energy consumption of mobile devices. Our method presents three contributions. First, we jointly and intelligently select the optimal subset of access points for positioning via maximum mutual information criterion. Second, we further propose local discriminant embedding algorithm for nonlinear discriminative feature extraction, a process that cannot be effectively handled by existing linear techniques. Third, to reduce complexity and make input signal space more compact, we incorporate clustering analysis to localize the positioning model. Experiments in realistic environments demonstrate that the proposed method can lower energy consumption while achieving higher accuracy compared with previous methods. The improvement can be attributed to the capability of our method to extract the most discriminative features for positioning as well as require smaller computation cost and shorter sensing time.

Fabrication of binary polymer surfaces: selective embedment of polystyrene and poly(ε-caprolactone) onto polypropylene surface structures

We report a simple method for controlled embedment of polymer components within injection molded polymer surface structures. The structures were micro-sized channels and pits with various step-size ratios. Two types of affinity differences were created between the top and the bottom of the structures which allowed a selective deposition of embedded components. The dissolved embedding components were spread onto the sample by spin coating. Solvent and thermal annealing then facilitated the phase separation of them from the upper surface and segregated them into the structure bottoms. Our results show that with the optimal step-size ratio, mobilized polymer components are capable of traveling across a leveled structure top. With the thiol customized affinity difference, the proposed method is applicable for the embedment of special components, such as nanoparticles, cells and biomolecules, in addition to polymer components.

Nickel-assisted growth and selective doping of spinel-like gallium oxide nanocrystals ingermano-silicate glasses for infrared broadband light emission

The target of taking advantage of the near-infrared light-emission properties of nickelions in crystals for the design of novel broadband optical amplifiers requires theidentification of suitable nanostructured glasses able to embed Ni-doped nanocrystalsand to preserve the workability of a glass. Here we show that Ni doping ofLi2O–Na2O–Ga2O3–GeO2–SiO2 glass (with composition 7.5:2.5:20:35:35 and melting temperature1480 °C, sensibly lower than in Ge-free silicates) enables the selective embedding of nickel ions inthermally grown nanocrystals of spinel-like gallium oxide. The analysis of transmission electronmicroscopy and x-ray diffraction data as a function of Ni-content (from 0.01 to 1 mol%) indicatesthat Ni ions promote the nanophase crystallization without affecting nanoparticle size (∼6 nm) andconcentration (∼4 × 1018 cm − 3). Importantly, as shown by optical absorption spectra, all nickel ions enter into the nanophase, with anumber of ions per nanocrystal that depends on the nanocrystal concentration and ranges from 1 to102. Photoluminescence data indicate that fast non-radiative decay processes become relevantonly at mean ion–ion distances shorter than 1.4 nm, which enables the incorporation of afew Ni ions per nanoparticle without too large a worsening of the light-emission efficiency.Indeed, at 0.1 mol% nickel, the room temperature quantum yield is 9%, with an effectivebandwidth of 320 nm.

Robust Video Data Hiding Using Forbidden Zone Data Hiding and Selective Embedding

Video data hiding is still an important research topic due to the design complexities involved. We propose a new video data hiding method that makes use of erasure correction capability of repeat accumulate codes and superiority of forbidden zone data hiding. Selective embedding is utilized in the proposed method to determine host signal samples suitable for data hiding. This method also contains a temporal synchronization scheme in order to withstand frame drop and insert attacks. The proposed framework is tested by typical broadcast material against MPEG-2, H.264 compression, frame-rate conversion attacks, as well as other well-known video data hiding methods. The decoding error values are reported for typical system parameters. The simulation results indicate that the framework can be successfully utilized in video data hiding applications.

An Efficient Prediction-and-Shifting Embedding Technique for High Quality Reversible Data Hiding

The embedding capacity of a histogram-based reversible data hiding technique is primarily determined by the peak height of the histogram. Recently, some studies have tried to embed data in the histogram of prediction errors by modifying the error values and have better embedding efficiency. However, these methods offer no selective embedment mechanism to exclude the positions where the modification in the embedding operation contributes no capacity but merely degrade the image quality. In this paper, a novel coding method for reversible data hiding is presented. A two-stage prediction algorithm that fully exploits the pixel correlations is employed to create more embeddable spaces, and a selective embedment mechanism is used to enhance the image quality. According to the experimental results, the proposed method achieved the highest payload while maintaining the lowest distortion for most standard test images, comparing to other existing histogram-shifting-based reversible data hiding techniques.

Information Hiding for G.711 Speech Based on Substitution of Least Significant Bits and Estimation of Tolerable Distortion

In this paper, we propose a novel data hiding technique for G.711-coded speech based on the LSB substitution method. The novel feature of the proposed method is that a low-bitrate encoder, G.726 ADPCM, is used as a reference for deciding how many bits can be embedded in a sample. Experiments showed that the method outperformed the simple LSB substitution method and the selective embedding method proposed by Aoki. We achieved 4-kbit/s embedding with almost no subjective degradation of speech quality, and 10kbit/s while maintaining good quality.

`Print and Scan' Resilient Data Hiding in Images

Print-scan resilient data hiding finds important applications in document security and image copyright protection. This paper proposes methods to hide information into images that achieve robustness against printing and scanning with blind decoding. The selective embedding in low frequencies scheme hides information in the magnitude of selected low-frequency discrete Fourier transform coefficients. The differential quantization index modulation scheme embeds information in the phase spectrum of images by quantizing the difference in phase of adjacent frequency locations. A significant contribution of this paper is analytical and experimental modeling of the print-scan process, which forms the basis of the proposed embedding schemes. A novel approach for estimating the rotation undergone by the image during the scanning process is also proposed, which specifically exploits the knowledge of the digital halftoning scheme employed by the printer. Using the proposed methods, several hundred information bits can be embedded into images with perfect recovery against the print-scan operation. Moreover, the hidden images also survive several other attacks, such as Gaussian or median filtering, scaling or aspect ratio change, heavy JPEG compression, and rows and/or columns removal

Selective Molecular Adsorption into a Nano Domain from Solution

Selective molecular adsorption from a mixture solution of two molecules by a scanning tunneling microscope (STM)-tip scratching is reported. A mono-molecular layer of perylene-3,4,9,10-tetracarboxylic dianhydride vacuum-deposited on freshly cleaved (0001) surface HOPG is used as a canvas layer for embedding another molecule; a small molecule (3-imino-4,5,6,7-tetrachloroisoindolin-1-one) or a long-chain molecule (10,12-pentacosadiynoic acid) in a solution of phenyloctane. As a result, the size of the scratched area in individual scratching, in other words, the molecular size of the adsorbate, is essential in the selective embedding of molecules. Since the molecular size is a key factor in adsorption into scratched regions, it is possible to make nano domains with a particular component molecule selectively from a mixed solution by employing this molecular size dependency.

Modification of dust-grain structure by sputtering

We have applied the SRIM computer code to study the sputtering of some likely astrophysical grain materials, and we have shown that selective embedding of metallic projectiles offers a partial explanation of gas-phase depletions. We show that supernova shockwaves sweep a significantly larger mass of interstellar gas per unit time than the shockwaves generated by outflows in star-forming regions. We apply our sputtering model to the bombardment levels expected in a supernova shock, and show that net embedding may dominate over net sputtering, leading to grain growth under some circumstances, particularly when the bombarding gas is enriched with metals from the supernova progenitor star. A combination of short cooling times and net embedding mean that it is possible for a type II supernova to generate more dust that it destroys, and we conclude that, in general, the sputtering process often leads to a compositional change in the grain material rather than simply to grain erosion.

Reversible EZW-based image compression using best-transform selection and selective partial embedding

A best-transform selection method and a selective partial embedding technique are proposed for use in a reversible embedded image compression system based on the embedded zerotree wavelet (EZW) coding scheme. Together, these approaches are shown to yield significantly better compression performance than a baseline system employing fully embedded EZW coding in conjunction with a single fixed transform, such as the S+P transform.

The nuclear lamina in male generative cells ofGinkgo biloba

Using selective extraction and diethylene glycol distearate embedment and embedment-free electron microscopy, we demonstrated nuclear lamina-like structures in sperm cells ofGinkgo biloba. A well-organized nuclear matrix network was also observed. Further studies were undertaken to determine whether or not lamin-like components exist in the pollen and sperm cells. Immunofluorescence staining using monoclonal antibodies against different animal lamins revealed lamins localized in the nuclear compartment of the sperm cells. Western blotting showed that in pollen grains there are two positive crossreaction bands at 66 kDa and 86 kDa, recognized by antibodies specific to animal lamins; in sperm cells there was only one, at 66 kDa. These results indicate that nuclear lamina containing both A-type and B-type lamins was present in male generative cells ofG. biloba. The data imply that plant lamins share some homology with animal lamins and may be conserved during evolution.

Improved selective growth of InP around dry-etched mesas by metalorganic chemical vapor deposition at low growth temperature

A comparative study has been carried out regarding selective embedding growth of InP by metalorganic chemical vapor deposition (MOCVD) around dry-etched mesas, using two types of reactors: a conventional horizontal type and a highspeed rotating-susceptor type. In the case of the conventional horizontal-type MOCVD, overgrowth on the mask was observed when the growth temperature was low (600°C). On the other hand, an almost planar grown surface without such overgrowth was achieved by using the high-speed rotating-susceptor MOCVD for a wide range of growth temperatures, especially even at a low growth temperature of 580°C. Regarding the high-speed rotating-susceptor MOCVD, we have also investigated the effects of dopants on the growth behaviors and have found a remarkable difference between n-type S-doped and p-type Zn-doped InP in the growth behaviors. The mechanism for suppressing overgrowth in case of the high-speed rotating-susceptor MOCVD, as well as the cause for the different effects between the dopants, are discussed.

MOVPE growth of InP around reactive ion etched mesas

We present a study of temporally resolved metalorganic vapour phase epitaxial growth of InP around reactive ion etched mesas in InP substrates. The experiments were performed at substrate temperatures in the range 580 to 680°C and for reactor pressures between 30 and 300 mbar. The planarity is primarily affected by substrate temperature, but to some extent also by the pressure. Planar and selective embedding is obtained around 1 μm wide and 1–4 μm high mesas at reactor pressures of 100 mbar and below, and for temperatures above 650°C without formation of any mask overhang. Overgrowth at low temperatures is found to be due to high growth rate at the mesa walls.

Selective embedding epitaxial technique of highly resistive InP for OEIC's device isolation

AbstractA device isolation layer for an opto‐electronics integrated circuit (OEIC) is desired to have not only an electrically isolating function but also an optical confinement function and low‐defect interface formation function. This paper describes a selective embedding epitaxial technique of highly resistive Fe‐doped InP by grown halide vapor phase epitaxy (VPE) for device isolation layer which has these functions. First, growth technique and growth conditions are examined for highly resistive Fe‐doped InP by grown hydride VPE, and it is shown that electrical characteristics sufficient for device isolation can be obtained. Also, characteristics of selective embedding growth are examined, and it is shown that a planar selective embedding growth is possible over a wide range of growth conditions. Furthermore, good results are obtained by applying this highly resistive layer to semiconductor lasers and OEIC devices.

InGaAsP/InP planar buried heterostructure lasers with semi-insulating InP current blocking layers grown by MOCVD

InGaAsP/InP planar buried heterostructure (BH) lasers with semi-insulating current blocking layers have been realized using LPE and MOCVD hybrid growth. The planar structure has been obtained by developing the selective embedding growth in MOCVD. Low threshold current of 17 mA and high efficiency of 42 percent have been attained with the BH lasers. Small-signal modulation bandwidth of 10 GHz has also been achieved.