Simultaneous Information Research Articles

FM-Unet: Biomedical image segmentation based on feedback mechanism Unet

<abstract><p>With the development of deep learning, medical image segmentation technology has made significant progress in the field of computer vision. The Unet is a pioneering work, and many researchers have conducted further research based on this architecture. However, we found that most of these architectures are improvements in the backward propagation and integration of the network, and few changes are made to the forward propagation and information integration of the network. Therefore, we propose a feedback mechanism Unet (FM-Unet) model, which adds feedback paths to the encoder and decoder paths of the network, respectively, to help the network fuse the information of the next step in the current encoder and decoder. The problem of encoder information loss and decoder information shortage can be well solved. The proposed model has more moderate network parameters, and the simultaneous multi-node information fusion can alleviate the gradient disappearance. We have conducted experiments on two public datasets, and the results show that FM-Unet achieves satisfactory results.</p></abstract>

FM-Unet: Biomedical image segmentation based on feedback mechanism Unet.

With the development of deep learning, medical image segmentation technology has made significant progress in the field of computer vision. The Unet is a pioneering work, and many researchers have conducted further research based on this architecture. However, we found that most of these architectures are improvements in the backward propagation and integration of the network, and few changes are made to the forward propagation and information integration of the network. Therefore, we propose a feedback mechanism Unet (FM-Unet) model, which adds feedback paths to the encoder and decoder paths of the network, respectively, to help the network fuse the information of the next step in the current encoder and decoder. The problem of encoder information loss and decoder information shortage can be well solved. The proposed model has more moderate network parameters, and the simultaneous multi-node information fusion can alleviate the gradient disappearance. We have conducted experiments on two public datasets, and the results show that FM-Unet achieves satisfactory results.

Duration judgments are mediated by the similarity with the temporal context

When we try to assess the duration of an event, we are often affected by external information. Studies on multiple timing have found that simultaneous timing information can produce an averaging or central tendency effect, where the perceived duration of the elements tends to be biased towards a general average. We wanted to assess how this effect induced by simultaneous distractors could depend on the temporal similarity between stimuli. We used a duration judgment task in which participants (n = 22) had to compare the duration of two identical targets (1 s) accompanied by simultaneous distractors of different durations (0.3, 0.7, 1.5 or 3 s). We found a central tendency effect, where duration judgments of the target were systematically biased towards the duration of the distractors that accompanied them. We put forward a model based on the concept of duration-channels that can explain the central tendency effect with only one estimated parameter. This parameter modulates the rate of decay of this effect as distractors duration become more different than the duration of the target.

Simultaneous distributed acoustic sensing and communication over a two-mode fiber.

We designed and tested a distributed acoustic sensing (DAS) that co-exists with optical communication over a two-mode fiber (TMF). In particular, we excited both linearly polarized (LP) modes, LP01 and LP11a, using a photonic lantern for simultaneous information signal transmission while collecting the backscattered Rayleigh light at the near end of the fiber to detect vibrations from a predetermined source. While transmitting data using on-off keying (OOK) or orthogonal frequency-division multiplexing (OFDM) modulation schemes, the optical fiber DAS offers high signal-to-noise ratio (SNR) values that are always larger than the minimum acceptable 2 dB SNR. In addition, as a proof-of-concept experiment, we report parallel sensing and OFDM transmission achieving a data rate of up to 4.2 Gb/s with a bit error rate (BER) of 3.2 × 10-3.

On the Performance of SLIPT-Enabled DF Relay-Aided Hybrid OW/RF Network

Thisarticle investigates a decode-and-forward (DF) relay-aided hybrid optical wireless/radio frequency (OW/RF) network. The OW subsystem exploits simultaneous transfer of energy and information to increase the system’s lifespan. The end-to-end signal-to-noise ratio statistics are derived using the optical energy transfer at the DF relay. For the proposed DF relay-aided hybrid OW/RF system, Malaga ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\mathcal {M}$</tex-math></inline-formula> )-distribution with non-zero boresight pointing/misalignment error is considered to model the OW channel, and Nakagami- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$m$</tex-math></inline-formula> model is assumed for the RF channel. In particular, analytical expressions of outage probability (OP), average bit error rate (BER), ergodic capacity, and effective capacity are derived in terms of Meijer’s G-function. To gain additional insights, we also derive the asymptotic expressions of average BER, OP, and effective capacity and estimate the diversity order mathematically. The impact of various system and channel parameters like dc bias, turbulence, weather conditions, and visibility is explored on the system performance. Through numerical results, we show that the proposed DF relay-aided and simultaneous lightwave information and power transfer (SLIPT) -enabled hybrid OW/RF system surpasses its amplify-and-forward-based counterpart. The superiority of the proposed system over non-energy harvesting (EH) and RF-EH-based hybrid OW/RF system is also shown. The analytical formulations are validated with the Monte-Carlo simulations.

Spectral imaging at high definition and high speed in the mid-infrared.

Spectral imaging in the mid-infrared (MIR) range provides simultaneous morphological and chemical information of a wide variety of samples. However, current MIR technologies struggle to produce high-definition images over a broad spectral range at acquisition rates that are compatible with real-time processes. We present a novel spectral imaging technique based on nondegenerate two-photon absorption of temporally chirped optical MIR pulses. This approach avoids complex image processing or reconstruction and enables high-speed acquisition of spectral data cubes (xyω) at high-pixel density in under a second.

Optimization of a Mobile Optical SWIPT System With Asymmetric Spatially Separated Laser Resonator

High-power and high-rate simultaneous wireless information and power transfer (SWIPT) becomes more and more important with the development of Internet of Things technologies. Optical SWIPT, also known as simultaneous light information and power transfer (SLIPT), has unique advantages such as abundant spectrum resources and low propagation divergence, compared with radio-frequency (RF) SWIPT. However, optical SWIPT faces many challenges in beam steering and receiver positioning/tracking. Resonant beams generated by spatially separated laser resonators (SSLR) have many advantages, including high power, self-aligned mobility, and intrinsic safety. It has been proposed as the carrier of wireless charging and communication. Using resonant beams, mobile electronic devices can be remotely charged and supported with high-rate data transfer. In this paper, we propose a mobile optical SWIPT system based on asymmetric SSLR and present the system optimization procedure. We also determine the boundary of the charging power and communication rate, and discuss the trade-off between power transfer and information transfer. Numerical results show that both the charging power and the communication rate of the optimized asymmetric system are much higher than those of the symmetric system in the previous work.

Energy-efficient subchannel assignment and power allocation in VLC-IoT systems with SLIPT.

In this paper, we investigate joint subchannel assignment and power allocation for the energy efficiency (EE) optimization in an indoor visible light communication (VLC)-Internet of Things (IoT) system with simultaneous lightwave information and power transfer (SLIPT). A mixed-integer fractional nonlinear programming problem that is challenging to solve is formulated. To tackle this problem, the optimal transmission scheme is decomposed into subchannel assignment and power allocation. Firstly, a virtual cell formation and subchannel assignment (VCF-SA) scheme is proposed, which considers the location of IoT devices, quality of service requirements, and energy states. Secondly, a quadratic transformation-based power allocation (QTBPA) scheme is designed to transform the fractional nonlinear programming problem into a series of convex problems that can be solved iteratively. Simulation results illustrate the effectiveness of the proposed scheme in terms of system EE compared to the benchmarks. The impact of system parameters on the EE is also analyzed.

Towards routine 3D characterization of intact mesoscale samples by multi-scale and multimodal scanning X-ray tomography

Non-invasive multi-scale and multimodal 3D characterization of heterogeneous or hierarchically structured intact mesoscale samples is of paramount importance in tackling challenging scientific problems. Scanning hard X-ray tomography techniques providing simultaneous complementary 3D information are ideally suited to such studies. However, the implementation of a robust on-site workflow remains the bottleneck for the widespread application of these powerful multimodal tomography methods. In this paper, we describe the development and implementation of such a robust, holistic workflow, including semi-automatic data reconstruction. Due to its flexibility, our approach is especially well suited for on-the-fly tuning of the experiments to study features of interest progressively at different length scales. To demonstrate the performance of the method, we studied, across multiple length scales, the elemental abundances and morphology of two complex biological systems, Arabidopsis plant seeds and mouse renal papilla samples. The proposed approach opens the way towards routine multimodal 3D characterization of intact samples by providing relevant information from pertinent sample regions in a wide range of scientific fields such as biology, geology, and material sciences.

Evolution of surface properties of titanium oxide thin films

Titanium oxide thin films were deposited by rf magnetron sputtering of Ti metallic target in flow-controlled O2 + Ar atmosphere. Comprehensive investigations of crystallographic structure, phase composition, morphology and optical properties were performed by means of X-ray diffraction, X-ray reflectivity (XRR), scanning electron microscopy, optical spectrophotometry, and X-ray photoemission spectroscopy. It was found that as the O2/(O2 + Ar) flow ratio increased, the microstructure of thin films changed from TiO, Ti2O3, to rutile TiO2, rutile-anatase mixture and, finally, to pure anatase. Special emphasis was given to soft X-ray absorption spectroscopy in surface-sensitive total electron yield mode, which provided simultaneous information on electronic occupancy and local atomic structure. Studies of titanium L23 edge revealed systematic changes in crystal field strength, increasing upon rutile formation and decreasing when anatase became the dominant phase in sputtered films. Diffuse reflectance and XRR were employed to investigate the light scattering effects related to the surface roughness. The highest value (5.3 nm) of XRR roughness was observed for pure rutile sample. Performance of films as photoanodes in photoelectrochemical cells was assessed by photocurrent vs potential and time measurements. Results revealed that crystallized, stoichiometric films containing a mixture of anatase and rutile were promising photoanode materials for green hydrogen generation.

Particle beam deflection imaging for simultaneous characterization of aerosol particle size and charge

We present a novel method referred to as Particle Beam Deflection Imaging (PBDI) for the simultaneous characterization of the size and electric charge distribution of submicrometer (currently ∼200–800 nm) aerosol particles in real-time (currently ≤30 s). It combines aerodynamic and electrostatic particle deflection, providing two-dimensional information on size and charge in a single two-dimensional light scattering image. The image allows one to extract information on charge-averaged and charged-resolved particle size distributions, and on size-dependent bipolar charge distributions. The current prototype has a size resolution of <50 nm and can resolve individual charge states. Compared to Scanning Mobility Particles Sizers (SMPS), the PBDI offers the advantage of providing simultaneous size and charge information at higher size resolution in a significantly shorter measurement time, hence allowing real-time characterization of volatile aerosol particles.

Reconfigurable Intelligent Surface-Aided Joint Radar and Covert Communications: Fundamentals, Optimization, and Challenges

Future wireless communication systems will evolve toward multifunctional integrated systems to improve spectrum utilization and reduce equipment sizes. Joint radar and communication (JRC) systems, which can support simultaneous information transmission and target detection, have been regarded as a promising solution for emerging applications, such as autonomous vehicles. In JRC, data security and privacy protection are critical issues. Thus, we apply covert communication to JRC and propose a joint radar and covert communication (JRCC) system to simultaneously achieve high spectrum utilization and secure data transmission.

Estimating Hydraulic Conductivity, Transmissibility and Specific Yield of Aquifer in Barind Area, Bangladesh Using Pumping Test

Reliable hydraulic parameters values are essential and crucial basic data for potential groundwater withdrawal (aquifer yield) and also for sustainable groundwater management. They are also essential for simulation model study for different management scenario analyses. The laboratory test has limitations, while in situ tests produce representative aquifer parameters. The pumping test method is the only method that provides simultaneous information on the hydraulic behavior of the well, the aquifer, and the aquifer boundaries. Pumping tests were performed to determine aquifer hydraulic properties such as hydraulic conductivity (K), transmissibility (T), and specific yield (Sy) at two Upazilas of the Barind area, namely Nachol and Niamatpur. The aquifer formation is composed of layers: upper fine sand, medium sand, a conductive sand layer, and lower fine sand at the bottom, below which the impervious clay layer exists. The K was determined through Dupit’s steady radial flow equation, T through Theis’s and Copper-Jacob approach, and Sy through Copper-Jacob and gravity drainage of aquifer materials. The mean K, T, and Sy were found as 30.3 m3/m2/day, 756.7 m3/m/day, and 4.6%, respectively for the Nachol location; and 52.7 m3/m2/day, 1027.3 m3/m/day and 6.6%, respectively for Niamatpur location. The values obtained are supported by regional values reported earlier, and also by other locations’ values situated elsewhere having similar aquifer materials. To achieve long-term sustainability in the studied locations, withdrawal of groundwater resources should be optimized considering the aquifer hydraulic properties values.

Cancer Stem Cell Derived Extracellular Vesicles with Self-Functionalized 3D Nanosensor for Real-Time Cancer Diagnosis: Eliminating the Roadblocks in Liquid Biopsy.

Liquid biopsy for determining the presence of cancer and the underlying tissue of origin is crucial to overcome the limitations of existing tissue biopsy and imaging-based techniques by capturing critical information from the dynamic tumor heterogeneity. A newly emerging liquid biopsy with extracellular vesicles (EVs) is gaining momentum, but its clinical relevance is in question due to the biological and technical challenges posed by existing technologies. The biological barriers of existing technologies include the inability to generate fundamental details of molecular structure, chemical composition as well as functional variations in EVs by gathering simultaneous information on multiple intra-EV molecules, unavailability of holistic qualitative analysis, in addition to the inability to identify tissue of origin. Technological barriers include reliance on EV isolation with a few labeled biomarkers, resulting in the inability to generate comprehensive information on the disease. A more favorable approach would be to generate holistic information on the disease without the use of labels. Such a marker-free diagnosis is impossible with the existing liquid biopsy due to the unavailability clinically validated cancer stem cells (CSC)-specific markers and dependence of existing technologies on EV isolation, undermining the clinical relevance of EV-based liquid biopsy. Here, CSC EVs were employed as an independent liquid biopsy modality. We hypothesize that tracking the signals of CSCs in peripheral blood with CSC EVs will provide a reliable solution for accurate cancer diagnosis, as CSC are the originators of tumor contributing to tumor heterogeneity. We report nanoengineered 3D sensors of extremely small nano-scaled probes self-functionalized for SERS, enabling integrative molecular and functional profiling of otherwise undetectable CSC EVs. A substantially enhanced SERS and ultralow limit of detection (10 EVs per 10 μL) were achieved. This was attributed to the efficient probe-EV interaction due to the 3D networks of nanoprobes, ensuring simultaneous detection of multiple EV signals. We experimentally demonstrate the crucial role of CSC EVs in cancer diagnosis. We then completed a pilot validation of this modality for cancer detection as well as for identification of the tissue of origin. An artificial neural network distinguished cancer from noncancer with 100% sensitivity and 100% specificity for three hard to detect cancers (breast, lung, and colorectal cancer). Binary classification to distinguish one tissue of origin against all other achieved 100% accuracy, while simultaneous identification of all three tissues of origin with multiclass classification achieved up to 79% accuracy. This noninvasive tool may complement existing cancer diagnostics, treatment monitoring as well as longitudinal disease monitoring by validation with a large cohort of clinical samples.

Investigations on simultaneous multi-color photometry survey for GEO region

Optical surveys play significant roles in space object monitoring and catalog, especially for some unique high-altitude regions like the Geosynchronous Earth Orbit (GEO) region. For object classes identification and space environment models development, besides the orbits additional information like physical properties are required. Non-resolving observation techniques like color photometry can provide such knowledge. Here simultaneous surveys for GEO region in g’r’i’ bands were performed utilizing the CHanging Event Survey (CHES) system of Purple Mountain Observatory. Based on the large amounts of images, the object detection, catalog correlation and multi-color photometry are performed consecutively. Due to the extremely wide field of view of CHES system, the simultaneous multi-band information of 1697 objects is obtained. The distribution and clustering behavior of their color indexes are preliminarily investigated, and the evolution of color with launch age is also analyzed. It is demonstrated that even for the same object class the distribution of color index may be different, and for various objects of the same class multiple clusters of color index are found. It indicates that the color photometry can help to classify object classes and provide useful information for correlating new observations with catalog.

Negatively Biased Solar Cell Optical Receiver for Underwater Wireless Optical Communication System With Low Peak Average Power Ratio

Charging batteries in underwater scenarios is generally very expensive and impractical, and solar cell (SC)-based underwater simultaneous lightwave information and power transfer (SLIPT) systems are a powerful solution. However, silicon SC receiver devices have limited bandwidth and are prone to deep signal-to-noise (SNR) degradation during underwater light fading effects. For these problems, this manuscript proposes a negative-biased SC optical receiver scheme to increase the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$-3$</tex-math></inline-formula> dB bandwidth of silicon SC from 440 kHz to 780 kHz. For the deep fading of SNR caused by various degradation effects in the water environment, a low peak average power ratio (PAPR) discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) modulation scheme is employed to counteract the deep fading phenomenon in the system. Achieved a communication rate of 15.2 Mbps in a 60 cm underwater environment with a fading factor of 0.403 and a bit error rate (BER) of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$1.59\times 10^{-3}$</tex-math></inline-formula> under perturbation. Also, the performance of DFT-S-OFDM and orthogonal frequency division multiplexing (OFDM) modulation systems in water environments with different turbidity (absorption characteristics and scattering) and presence of disturbances are compared separately, and the DFT-S-OFDM system is more robust. Finally, we complete the energy harvesting during the communication process, and the experiments show that the total battery power efficiency of the energy harvesting system can be increased by 1.87 times under the white light-emitting diode (LED) continuous irradiation for three hours.

Excitatory postsynaptic current model for synaptic thin-film transistors

Synaptic devices that mimic biological neurons have attracted much attention for brain-inspired neuromorphic computing. Especially, synaptic thin-film transistors (TFTs) have emerged with simultaneous signal processing and information storage advantages. However, the analysis of excitatory postsynaptic current (EPSC) relies on an empirical model such as a serial RC circuit, which limits a systematic and in-depth study of synaptic devices in terms of material and electrical properties. Herein, the single-pulse-driven synaptic EPSC (SPSE) model, including capacitive effect and information of the synaptic window, is analytically proposed. The SPSE model can simulate EPSC of synaptic devices at given TFT-operating conditions. EPSC with the SPSE model can be characterized with quantified parameters for the capacitive effects and the synaptic windows, which also depend on the electrical condition applied to TFTs. Various kinds of synaptic-TFTs with different gate insulators (e.g., SiO2 and ion-gel) are used to confirm the performance of the SPSE model. For example, the SPSE model can capture the long-term robustness of ion-gel-based TFTs with specific quantified parameters. In addition, the SPSE model enables the estimation of energy consumption, which can potentially be leveraged to compare the energy cost of EPSC fairly. The SPSE model can provide a guideline to understand the physical properties of synaptic TFTs.

Theorizing Human Information Systems Through the Postmodern Juxtaposition of Quantum Entanglements

Purpose: In the context of knowledge management, we argue that there is no singular way to understand our own reality because we are constantly entangled in a juxtaposed plurality of postmodern information systems. Humans define their realities and worldviews through culture, ethnicity, language, semiotics, systems of meanings, communities of practice, and other physical and sensory interpretations within information systems. But since multiple factors in time and space define one's information systems, we theorize that alternative interpretive models exist for applications of the same situations when perceived by others. Study design/methodology/approach: We explored this inherent knowledge management phenomenon of human information systems entanglements through the literature review of respected scientists, theorists, academics, and philosophers; and herein present our theory of entangled human information systems. Findings: Since all human information systems are dependent upon the continuous management of tacit and explicit knowledge, and the understandings and meanings of the individual experiencing the situation, they may be matrixed, nested, and overlapped with multiple information systems; and because they can exist alone, apart, together, or at different times and places and survive, they are entangled. We theorize that similar to a movable quantum particle, human information systems are also entangled, superpositioned, and juxtaposed in two or more states concurrently; and when interpreted and applied pluralistically, they create an infinite number of simultaneous human information systems in which we reside. Originality/value: This qualitative approach to inquiry focuses upon understanding the construct of human information systems entanglements and their similarities to quantum entanglements, by exploring the “how” and “why” they occurs, rather than examining the “what” and “how many.”

Simultaneous lightwave information and power transfer in optical wireless communication networks: An overview and outlook

Objectives:The main objective of this article is to provide a critical review of up-to-date contributions to simultaneous lightwave information and power transfer (SLIPT) in optical wireless communication (OWC) networks. Methods:The first section of this article emphasizes the need for the exploitation of optical signals for energy harvesting purposes in order to develop a sustainable OWC system. In the second section, we provide basic guidelines to be considered for designing an efficient SLIPT system. In the third section, SLIPT structure from the viewpoint of transceiver architecture is analyzed with respect to achievable rate and harvested energy. The fourth section provides a critical review of various articles on SLIPT in OWC networks. Results:Our main findings from the analysis in section three show that receiver diversity can be achieved using multiple photodetectors. Consequently, this leads to an improved achievable rate and harvested energy of the SLIPT receivers. Also, based on the limitations of papers presented in section four, we are able to unlock several open issues and potential solutions that can be explored as future research areas. Conclusions:SLIPT is considered to be a key promising technique that can be used in developing green OWC networks. In this article, the performance of SLIPT receivers and various articles on SLIPT-related designs have are presented. Based on the transceiver analysis, limitations and design challenges of the articles presented, several areas that can be explored for future research work are identified. Thus, more contributions are still needed toward developing efficient SLIPT-based systems.

Performance of a High Power and Capacity Mobile SLIPT Scheme

The increasing demands of power supply and data rate for mobile devices promote the research of simultaneous wireless information and power transfer (SWIPT). Optical SWIPT, as known as simultaneous light information and power transfer (SLIPT), has the potential for providing high-capacity communication and high-power wireless charging. However, SLIPT technologies based on light-emitting diodes have low efficiency due to energy dissipation over the air. Laser-based SLIPT technologies need strict positioning accuracy and scanning resolution, which may lead to the increase of costs and complexity. In this paper, we propose a mobile SLIPT scheme based on spatially separated laser resonator (SSLR) and intra-cavity second harmonic generation. The power and data are transferred via separated frequencies, while they share the same self-aligned resonant beam path, without the needs of receiver positioning and beam steering. We establish the analysis model of the resonant beam power and its second harmonic power. Numerical results show that the proposed system can achieve watt-level battery charging power and above 10-bit/s/Hz achievable rate at 6-m distance, which satisfies the requirements of most indoor mobile devices.