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Underlay coexistence is a spectrum efficient mechanism to roll out 5G picocells within a macrocell on the same spectrum. Due to a lack of cooperation between the primary users (PUs) in the macrocell and secondary users (SUs) in the picocells, it is impossible to have complete knowledge of channel conditions between them. Under such a circumstance, chance-constrained programming (CCP) has been shown to be an ideal optimization tool to address such a channel uncertainty. However, solutions to CCP are computationally intensive and cannot meet 5G's timing requirement (125 s). To address this problem, we propose a novel scheduler called GPU-based Underlay Coexistence (GUC) with the goal of finding an approximate solution to CCP in real-time. The essence of GUC is to decompose the original optimization problem into a large number of small subproblems that are suitable for parallel computation on GPU platforms. By selecting a subset of promising subproblems and solving them in parallel with fast algorithms, we are able to leverage GPU parallel computing and develop a real-time solution. Through extensive experiments, we show that GUC meets the 125 s requirement while achieving 90% optimality on average.

The Ganga-Padma moribund deltaic zone contains plenty of small seasonal wetlands. In this paper we mapped the temporal hydrological dynamics of floodplain wetlands in the Ganga-Padma moribund deltaic zone. To evaluate the trend in wetland changes over time we used a time-series of Landsat images from 1987 to 2016 and adopted Water Presence Frequency (WPF), Standard Deviation, and Trend Analysis for stability and trend of water presence and change over time. Normalized Difference Water Index is used for wetland mapping for both pre- and post-monsoon seasons using the 30 years Landsat images. The result shows sequential changes in trend of wetland area and nature of deviation in water availability in wetland over time. More than 85% wetland area is prone to shallowing of depth and out of which 25% area is highly infected to this problem as found from wetland trend analysis. Standard deviation approach and trend analysis approach are used for detecting pixel-wise dynamics of wetland and trend of wetland change over the selected period of time based on the same images. The entire time spectrum is subdivided into three phases for detecting phasal change of water presence frequency (WPF) or stability of wetland. Among the total wetland area, 21.22% appeared as highly stable (high WPF) and 43.71% emerged as instable (low WPF). Only 14.56% wetland area recorded low departure in water availability, and these are usually found in the stable wetland part.

Spectrum occupancy measurements have become vital due to the proliferation of radio users. Literature shows that most of the allocated spectrum is used sporadically. This brings in the idea of dynamic spectrum access techniques using Cognitive Radios (CR). Little research attention has focussed on the real-time measurements of spectrum occupancy. Hence, the proposed research investigates the spectrum occupancy to determine how often frequency channels for TV bands are utilised. This was achieved by installing a low-cost spectrum sensor using Yagi Antennas to monitor the TV spectrum bands, applying statistical analysis tool for data processing. The study used Energy detection techniques to determine the spectrum occupation status, i.e., whether the spectrum is vacant or occupied. This study further explores the detailed pragmatic measurements study of spectrum occupancy with data from TV frequency band (470 – 702MHz).

Recently, there have been contrary claims of Kitaev spin-liquid behavior and ordered behavior in the honeycomb compound ${\mathrm{Ag}}_{3}\mathrm{Li}{\mathrm{Ir}}_{2}{\mathrm{O}}_{6}$ based on various experimental signatures. Our investigations on this system reveal a low-temperature ordered state with persistent dynamics down to the lowest temperatures. Magnetic order is confirmed by clear oscillations in the muon spin relaxation ($\ensuremath{\mu}\mathrm{SR}$) time spectrum below 9 K until 52 mK. Coincidentally in $^{7}\mathrm{Li}$ nuclear magnetic resonance, a wipeout of the signal is observed below $\ensuremath{\sim}10$ K, which again strongly indicates magnetic order in the low-temperature regime. This is supported by our density functional theory calculations which show an appreciable Heisenberg exchange term in the spin Hamiltonian that favors magnetic ordering. The $^{7}\mathrm{Li}$ shift and spin-lattice relaxation rate also show anomalies at $\ensuremath{\sim}50$ K. They are likely related to the onset of dynamic magnetic correlations, but their origin is not completely clear. Detailed analysis of our $\ensuremath{\mu}\mathrm{SR}$ data is consistent with a coexistence of incommensurate N\'eel and striped environments. A significant and undiminished dynamical relaxation rate ($\ensuremath{\sim}5$ MHz) as seen in $\ensuremath{\mu}\mathrm{SR}$ deep into the ordered phase indicates enhanced quantum fluctuations in the ordered state.

In the setting of the modal logic that characterizes modal refinement over modal transition systems, Boudol and Larsen showed that the formulae for which model checking can be reduced to preorder checking, that is, the characteristic formulae, are exactly the consistent and prime ones. This paper presents general, sufficient conditions guaranteeing that characteristic formulae are exactly the consistent and prime ones. It is shown that the given conditions apply to various behavioural relations in the literature. In particular, characteristic formulae are exactly the prime and consistent ones for all the semantics in van Glabbeek's linear time-branching time spectrum.

Music streaming, structured by an expanding network of social interdependencies (e.g. musicians, sound engineers, computer scientists and distributors) has made it easier to consume music in a wider number of social and private spaces and to a greater degree. This paper examines the emotional experience of contemporary music consumption by drawing from an Eliasian perspective, specifically Elias and Dunning’s sociology of leisure. We explore the relationship between work, spare time and leisure spaces, rather than examining specific spaces in isolation. We argue that music is used to demarcate, transition between, and blur space. Music plays an important role in facilitating the rhythm of routine, helping individuals to adjust to the demands of different spaces (based on varying intensities and immediacies of social pressures) and manage mood. The key characteristics of leisure that Elias and Dunning identify (motility, sociability and mimetic tension) are explored across the spectrum of time and space.

Mode-locking lasers have not only produced huge economic benefits in industrial fields and scientific research, but also provided an excellent platform to study diverse soliton phenomena. However, the real-time characterization of the ultrafast soliton dynamics remains challenging for traditional electronic instruments due to their relatively low response bandwidth and slow scan rate. Consequently, it is urgent for researchers to directly observe these ultrafast evolution processes, rather than just indirectly understand them from numerical simulations or averaged measurement data. Fortunately, dispersive Fourier transformation (DFT) provides a powerful real-time measurement technique to overcome the speed limitations of traditional electronic measurement devices by mapping the frequency spectrum onto the temporal waveform. In this review, the operation principle of DFT is discussed and the recent progress in characterizing the ultrafast transient soliton dynamics of mode-locking lasers is summarized, including soliton explosions, soliton molecules, noise-like pulses, rogue waves, and mode-locking buildup processes.

This study presents a COordinate rotation DIgital computer (CORDIC)-based novel architecture combining the sliding discrete Fourier transform (DFT) with Hann windowing to reduce the leakage effect of the DFT spectrum. The proposed architecture also presents a refreshing approach to minimise error due to the finite word-length in the output windowed spectrum compared with the existing method. The architecture can also be extended for other high order generalised cosine windows such as Blackman, Blackman-Harris, and flat-top. The post-route results on the Virtex-6 FPGA as well as the physical ASIC post-layout results are also presented for the proposed architecture.

We propose behavioral specification theories for most equivalences in the linear-time–branching-time spectrum. Almost all previous work on specification theories focuses on bisimilarity, but there is a clear interest in specification theories for other preorders and equivalences. We show that specification theories for preorders cannot exist and develop a general scheme which allows us to define behavioral specification theories, based on disjunctive modal transition systems, for most equivalences in the linear-time–branching-time spectrum.

The measurement of realistic exposure levels of quasi - stochastic signals from the IEEE 802.11ac communication standard was achieved by applying the complementary cumulative distribution function mode of a real - time spectrum analyzer connected to a laptop. Statistics were used to highlight the differences between the data transfer directions.

It is always an urgent problem to detect unauthorized access to spectrum by malicious devices in real time, such that the access of legal devices can be guaranteed. Dedicate spectrum sensing devices are extremely expensive and bulky, which can not be applied in normal scenario. We present S3, a real-time spectrum sensing and analyzing method, in which a smartphone is adopted as the upper computer to send instructions to a master control module of Raspberry Pi, and the master control module drives a Software Defined Radio (SDR) based spectrum sensing module. The real-time sensing results are displayed on the smartphone, and stored into a local database at the same time for further analyzing. We evaluate the accuracy and effectiveness of our S3 by comparing with a dedicated spectrum analyzer. Evaluation results demonstrate that S3 can achieve high accuracy realtime sensing. In average, the relative difference between S3 and its comparison is 1.045%. Furthermore, we implement four real-time spectrum analysis functions, including signal strength, channel occupancy, frequency band occupancy and waterfall plot.

The spatiotemporal analysis of the proteomic profile during human wound healing is a critical investigative step that can establish the complex interplay of molecular events that comprise the local response to burn injury. Partial-thickness wound samples with adjacent "normal" skin were collected from twenty-one patients with burn wounds and examined across a time spectrum ranging from the acute injury period at 3, 6, 11 days to the later hypertrophic scar period at 7 and 15 months. The techniques used for histology-directed tissue analyses highlighted inflammatory protein markers at the early time points after injury with diminished expression as burn wounds progressed into the proliferative phase. The datasets show the usefulness of MALDI MS and imaging mass spectrometry as discovery approaches to identify and map the cutaneous molecular sequence that is activated in response to the unique systemic inflammatory response following burn trauma. This information has the potential to define the unique factors that predispose human burn victims to disfiguring hypertrophic scar formation.

In cognitive radio network (CRN), a secondary user (SU) may utilize the spectrum resource of the primary user (PU) and avoid causing harmful interference to the primary network (PN) via spectrum sensing. In the traditional time spectrum sensing, the SU cannot detect the PU’s presence during its transmission, thus increasing interference to the PN. In this work, a novel weighed cooperative bandwidth spectrum sensing method is proposed, which allows multiple SUs to use part of the bandwidth to perform cooperative spectrum sensing throughout the whole frame in order to detect the PU’s reappearance in time. The SU’s spectrum efficiency is maximized by jointly optimizing sensing bandwidth proportion, number of cooperative SUs and detection probability, subject to the constraints on the SU’s interference and the false alarm probability. Simulation results show significant decrease on the interference and improvement on the spectrum efficiency using the proposed weighed cooperative bandwidth spectrum sensing method.

Objectives The fluorescent dye, 5-aminolevulinic acid (5-ALA), is currently applied for fluorescence-guided resections of high-grade gliomas. Present limitations of this technique are qualitative and subjective analyses, which show little of the background structures. This paper describes the intraoperative quantitative analysis of fluorescence intensity, hot-spot enhancement by frame averaging, and observation of surrounding structures by using 1000-nm lighting in real time. Patients and methods A sample of diluted protoporphyrin IX (PpIX) in a bottle and 37 samples from nine patients with brain lesions were involved in this study. In this preliminary study, we determined appropriate conditions for image averaging and filters and selected the most sensitive spectrometer. In addition, we utilized a 1000-nm lighting system to visualize surrounding structures with no interference from PpIX fluorescence. Results The novel system permitted the real-time quantitative analysis of PpIX fluorescence in operative fields by illuminating structures with 1000-nm-lighting. The real-time quantification provided subjective evaluations for surgical decision-making. We found good correlations between the fluorescence and PpIX contents in brain tissue. Furthermore, 1000-nm lighting visualized the anatomical structures and PpIX fluorescence simultaneously. Conclusion The combination of spectroscopy and a 1000-nm lighting system could enable surgeons to create a spectrogram of targets of interest while observing background structures. The spectrometer that we selected is highly sensitive to PpIX fluorescence and enables us to perform intraoperative real-time tissue mapping. By using a real-time system, we can perform quantitative and objective evaluations to achieve maximal tumor resection.

A real-time algorithm for spectrum balancing (SB) of digital subscriber lines (DSL) is proposed. A real-time SB algorithm is an algorithm for which the PSD and power regulatory constraints are always met after each iteration. The algorithm is based on fixed-point iterations and has a low computational complexity. Our simulations show that the proposed technique converges much faster than a recently proposed real-time SB algorithm. Moreover, the achievable bit rates by the algorithm are near-optimal. Particularly the algorithm outperforms the iterative SB (ISB) algorithm in large scenarios.

Real-time spectrum analyzer is a very useful novel measurement equipment for EMC troubleshooting and EMC educational purposes. In this paper is presented some basics and benefits of the real-time spectrum analyzers. In empirical part it is used two demoboards for measuring and demonstrating the effectiveness of the real-time spectrum analyzer in magnetic near-field measurement for EMC troubleshooting. This kind of demonstration measurement can be directly applied for the EMC educational purposes. The real-time spectrum analyzer is also very useful equipment for different wireless IoT device measurements.

Real time spectrum analysis is realized using a filterbank whose elements need special design. We propose the wavelets based and the wavelets packets based filter banks for the implementation of a digital real time spectrum analyzer and we show the advantages of our proposition by simulation examples.

We introduce the concept of an energy-detection Rotman-lens spectrum decomposer (RLSD) real-time spectrum-sniffer (RTSS) for cognitive radio. Compared to a previously existing RTSS, the RLSD-RTSS offers the advantages of being 1) Based an a simpler and lower-cost purely passive structure, 2) Easier to design and easily amenable to tunability, 3) Of much broader bandwidth, and 4) Of accommodating more channels. The electrical size of the device is electrically larger, but perfectly acceptable in the millimeter-wave frequency range. The proposed RLSD-RTSS is demonstrated theoretically and experimentally, and is shown to support tunability in terms of both bandwidth-resolution and operation band. Given its unique features, this device may find wide applications in 5G UHD and 3-D video systems.

A search for a time-varying $\bar{\nu}_{e}$ signal was performed with 621 days of data acquired by the Daya Bay Reactor Neutrino Experiment over 704 calendar days. The time spectrum of the measured $\overline{\nu}_e$ flux normalized to its prediction was analyzed with a Lomb-Scargle periodogram, which yielded no significant signal for periods ranging from 2 hours to nearly 2 years. The normalized time spectrum was also fit for a sidereal modulation under the Standard Model extension (SME) framework to search for Lorentz and CPT violation (LV-CPTV). Limits were obtained for all six flavor pairs $\bar{e}\bar{\mu}$, $\bar{e}\bar{\tau}$, $\bar{\mu}\bar{\tau}$, $\bar{e}\bar{e},\bar{\mu}\bar{\mu}$ and $\bar{\tau}\bar{\tau}$ by fitting them one at a time, constituting the first experimental constraints on the latter three. Daya Bay's high statistics and unique layout of multiple directions from three pairs of reactors to three experimental halls allowed the simultaneous constraint of individual SME LV-CPTV coefficients without assuming others contribute negligibly, a first for a neutrino experiment., Comment: 10 pages, 5 figures, 2 tables. Supplemental Material is provided. v3: updated two figures to better match published version

A monitoring system exploiting data analytics and cost-effective optical spectrum analyzers with under 1.2GHz resolution is proposed. Its performance is demonstrated in a filterless network experimental test-bed. The system enables prompt action before lightpath disruption. © 2018 OSA.

Spectral analysis plays an essential role in different applications. General-purpose spectrum analyzers are too expensive and are not appropriate for real-time applications. Therefore, a low-cost instrument for spectral analysis is needed. This paper describes a real-time field-programmable gate arrays implementation of a spectrum analyzer based on a modified periodogram of the input signal. It is able to detect and estimate the power and frequency of up to $N_{S}$ narrow-band signals given an analysis bandwidth, instantaneous dynamic range and frequency resolution.