Steady Source Research Articles

A Decentralized Asset Tokenization System using Ethereum

Abstract: Real estate is one of the most trusted investments that people have preferred. It provides a steady source of income which can be in the form of rent as well as lease. There are a number of advantages, but one of the key disadvantages of real estate investments is illiquidity. Although the global real estate investments are twice the size of investments in the equity markets, the number of investors in the real estate market is remarkably lower. Blockchain technology has real potential to solve the issues of illiquidity and transparency, and most importantly, it opens this very market to the retail investors as well. By creating Security Tokens, which are backed by real-world assets, real estate can be made more liquid with the help of Special Purpose Vehicles. These security tokens, which represent fractional ownership of the real estate can be traded by a trader / investor and these tokens can be listed on legitimate secondary exchanges. The robustness of Smart Contracts can be very efficient in transferring of tokens and also provide a seamless distribution of earnings amongst the investors / traders. This work describes Ethereum blockchain based solutions has the potential to make the existing Real Estate investment system much more efficient and reliable. Keywords: Tokenization , Blockchain , Fungible Assets, Tokens, Special Purpose Vehicle, Smart Contracts, Liquidity, Security Tokens,

A qualitative exploration of daily path and daily routine among people in Ukraine who inject drugs to understand associated harms

BackgroundPatterns of movement, heterogeneity of context, and individual space-time patterns affect health, and individuals’ movement throughout the landscape is shaped by addiction, meeting basic needs, and maintaining relationships. Place and social context enable or constrain behavior and individuals use social networks and daily routines to accomplish individual goals and access resources.MethodsThis article explores drug use as part of daily routines and daily paths among people who inject drugs in Dnipro City, Ukraine. Between March and August 2018, we interviewed 30 people who inject drugs living in Dnipro City, Ukraine. Study participants completed a single interview that lasted between 1 and 2 hours. During the interview, participants described their daily routine and daily path using a printed map of Dnipro as a prompt. Participants were asked to draw important sites; give time estimates of arrival and departure; and annotate on the map the points, paths, and areas most prominent or important to them. Participants also described to what extent their daily routines were planned or spontaneous, how much their daily path varied over time, and how drug use shaped their daily routine.ResultsWe identified 3 major types of daily routine: unpredictable, predictable, and somewhat predictable. Participants with unpredictable daily routines had unreliable sources of income, inconsistent drug suppliers and drug use site, and dynamic groups of people with whom they socialized and used drugs. Participants with predictable daily routines had reliable sources of income, a regular drug dealer or stash source, and a stable group of friends or acquaintances with whom they bought and/or used drugs. Participants with somewhat predictable daily routines had some stable aspects of their daily lives, such as a steady source of income or a small group of friends with whom they used drugs, but also experienced circumstances that undermined their ability to have a routinized daily life, such as changing drug use sites or inconsistent income sources.ConclusionsGreater attention needs to be paid to the daily routines of people who use drugs to develop and tailor interventions that address the place-based and social contexts that contribute to drug-use related risks.

Prospects and Challenges of Bond in Bangladesh Capital Market: A Comparison with Asian Capital Markets

The bond market always plays a complementary role in allocating funds from surplus sectors to different deficit sectors. In Bangladesh, an efficient bond market can play a vital role in supplementing the banking system to meet the requirements of the corporate sector for long-term capital investment and asset creation while providing a steady source of finance in the event of equity market volatility. The study has explored the prospects and challenges of the bond market in Bangladesh using secondary data from abundant sources. The study has addressed that the amount of tradable government bonds is negligible, secondary trading of government bonds is infrequent, and there has been scarcely any public issue of corporate bonds. It is observed that the bond market remains mostly underdeveloped to finance the large infrastructural projects in Bangladesh. The study has also compared the bond market of Bangladesh with twelve Asian nations and revealed that Bangladeshi bond market appears to be very insignificant in terms of the size and the corporate bond to Gross Domestic Product (GDP) ratio relative to those of countries. There are a plethora of impediments to the expansion of the bond market in Bangladesh, which have been attributed to major structural issues such as low investor base, absence of benchmark yield curve, lack of investor awareness and high issuance cost. For the smooth operation of a deep and liquid bond market in Bangladesh, a comprehensive regulatory framework, bond investment-friendly administrative infrastructure, and augmented investor incentives are recommended. It is a message of optimism that the regulatory authority has already taken initiatives to introduce several bonds with various features to make the capital market more vibrant.

QUANTIFICATION OF LEAF AND ROOT PLUMBAGIN IN PLUMBAGO ZEYLANICA FOLLOWED BY A COMPARATIVE STUDY WITH CALLUS AND COMMERCIAL SOURCE

Plumbago zeylanica shows the presence of many phytochemical constituents of which plumbagin, a type of naphthoquinone, is vital and has major biological effects. Plumbagin is majorly present in the root of the plants, with a minimal concentration in other parts of the plant. However, extracting plumbagin from the roots is destructive harvesting. Thus, micropropagation could be a viable alternative to reduce the collection of plant from wild. Study from micropropagated leaf calli was considered as a steady and sustainable source of phytochemical. P. zeyalnica callus was subcultured in an appropriate medium with plant growth regulators to initiate root cultures. A comparative study was performed to estimate the quantities of plumbagin obtain from the wild plant root part and root created by callus culture differentiation.

A Cost-Effective Method for Reconstructing City-Building 3D Models from Sparse Lidar Point Clouds

The recent popularization of airborne lidar scanners has provided a steady source of point cloud datasets containing the altitudes of bare earth surface and vegetation features as well as man-made structures. In contrast to terrestrial lidar, which produces dense point clouds of small areas, airborne laser sensors usually deliver sparse datasets that cover large municipalities. The latter are very useful in constructing digital representations of cities; however, reconstructing 3D building shapes from a sparse point cloud is a time-consuming process because automatic shape reconstruction methods work best with dense point clouds and usually cannot be applied for this purpose. Moreover, existing methods dedicated to reconstructing simplified 3D buildings from sparse point clouds are optimized for detecting simple building shapes, and they exhibit problems when dealing with more complex structures such as towers, spires, and large ornamental features, which are commonly found e.g., in buildings from the renaissance era. In the above context, this paper proposes a novel method of reconstructing 3D building shapes from sparse point clouds. The proposed algorithm has been optimized to work with incomplete point cloud data in order to provide a cost-effective way of generating representative 3D city models. The algorithm has been tested on lidar point clouds representing buildings in the city of Gdansk, Poland.

Agro-residues for clean electricity: in-lab trial of power generation from blended cocoa-kolanut wastes

As a way of wastes-to-voltage conversion, experimental benchtest trial of electricity generation from a blend of cocoa and kolanut harvest by-products is presented in this study. Bioethanol obtained from the blend, through a process of alcoholic fermentation, was mixed with gasoline at specific proportion and employed to fire a spark ignition engine that served as a prime-mover in driving a four-pole three-phase salient-pole synchronous machine. Performance of the driving machine, as the fuel-mix proportion and its speed of rotation varied, was studied. Likewise, the electric power output characteristic of the driven machine, when operated at its rated synchronous speed, was examined. It was found that the driving machine performed better on mixed fuel than pure gasoline. There were gradual increases in the torque and the power developed by the machine as the proportion of ethanol in the fuel-mix and the rotational speed increased. While the highest values of torque and power developed on using pure gasoline were 12.4 Nm and 2574 W respectively at 1900 rpm, 13.1 Nm torque and 2953 W power were obtained from the machine when ignited with 10%-bioethanol fuel-mix at the same speed. Also, with 90 Vdc excitation voltage and rotation at 1500 rpm synchronous speed, the driven machine continuously generated electricity at 207.6 Vrms (line-to-line), 1.169 A, 0.698 power factor, 48.17 Hz, 0.294 kW output. This study demonstrated the possibility of continuous generation of electric power from cocoa and kolanut wastes. Result obtained from the laboratory-based trial indicates that at such agricultural regions that are advantaged in the production of the two crops, harvest residues of the crops can be explored as a steady source of biofuel for off-grid microgrid electrification.

Electron Heat Source Driven Heat Transport in GaN at Nanoscale: Electron-Phonon Monte Carlo Simulations and a Two Temperature Model.

The thermal energy transport in semiconductors is mostly determined by phonon transport. However in polar semiconductors like GaN electronic contribution to the thermal transport is non-negligible. In this paper, we use an electron–phonon Monte Carlo (MC) method to study temperature distribution and thermal properties in a two-dimensional GaN computational domain with a localized, steady and continuous electron heat source at one end. Overall, the domain mimics the two-dimensional electron gas (2DEG) channel of a typical GaN high electron mobility transistor (HEMT). High energy electrons entering the domain from the source interact with the phonons, and drift under the influence of an external electric field. Cases of the electric field being uniform and non-uniform are investigated separately. A two step/temperature analytical model is proposed to describe the electron as well as phonon temperature profiles and solved using the finite difference method (FDM). The FDM results are compared with the MC results and found to be in good agreement.

Investigation of effective thermal conductivity of SiC foam ceramics with various pore densities

Abstract SiC foam ceramics are extensively used in numerous industrial applications that require high-temperature conditions. They can be used as thermal insulation, structural catalyst supports and energy storage materials. In this article, effective thermal conductivity of SiC foam ceramics at high temperature is studied by steady plane heat source method. This research aims to investigate the variations of effective thermal conductivity with pore density, stacking thickness, heat source temperature, and pore arrangement structure of foam ceramics. By a comparison of effective thermal conductivities of various pore density ceramic sheets, the experimental results show that the effective thermal conductivity of foam ceramics decreases with the increase of the pore density and stacking thickness. The effective thermal conductivity of the foam ceramics increases significantly when the heat source temperature is more than 200°C. For modular SiC foam ceramics, increasing the average pore density and sudden change of the pore density between ceramic sheets are not conducive to the increase of the effective thermal conductivity.

The emission properties, structure and stability of ionic liquid menisci undergoing electrically assisted ion evaporation

The properties and structure of electrically stressed ionic liquid menisci experiencing ion evaporation are simulated using an electrohydrodynamic model with field-enhanced thermionic emission in steady state for an axially symmetric geometry. Solutions are explored as a function of the external background field, meniscus dimension, hydraulic impedance and liquid temperature. Statically stable solutions for emitting menisci are found to be constrained to a set of conditions: a minimum hydraulic impedance, a maximum current output and a narrow range of background fields that maximizes at menisci sizes of 0.5–3 ${\rm \mu}{\rm m}$ in radius. Static stability is lost when the electric field adjacent to the electrode that holds the meniscus corresponds to an electric pressure that exceeds twice the surface tension stress of a sphere of the same size as the meniscus. Preliminary investigations suggest this limit to be universal, therefore, independent of most ionic liquid properties, reservoir pressure, hydraulic impedance or temperature and could explain the experimentally observed bifurcation of a steady ion source into two or more emission sites. Ohmic heating near the emission region increases the liquid temperature, which is found to be important to accurately describe stability boundaries. Temperature increase does not affect the current output when the hydraulic impedance is constant. This phenomenon is thought to be due to an improved interface charge relaxation enhanced by the higher electrical conductivity. Dissipated ohmic energy is mostly conducted to the electrode wall. The higher thermal diffusivity of the wall versus the liquid, allows the ion source to run in steady state without heating.

Generalized Disjunctive Programming Model for Optimization of Reverse Electrodialysis Process

Reverse electrodialysis (RED), an emerging electrochemical technology that uses ion-selective membranes to directly draw electricity out from salinity differences between two solutions, i.e., salinity gradient energy (SGE), has the potential to be a clean and steady renewable source to reach a sustainable water and energy supply portfolio. Although RED has made notable advances, full-scale RED progress demands more techno-economic and environmental assessments that consider full process design and operational decision space from module- to system-level. This work presents an optimization model formulated as a Generalized Disjunctive Programming (GDP) problem to define the cost-optimal RED process design for different deployment scenarios. We use a predictive model of the RED stack developed and validated in our research group to fully capture the behavior of the system. The problem addressed is to determine the RED plant's topology and the working conditions for a given design of each RED stack which renders the cost-optimal design for the defined problem and scenario. Our results show that, compared with simulation-based approaches, mathematical programming techniques are an efficient and systematic approach to provide decision-making support in early-stage applied research and to obtain design and operation guidelines for full-scale RED implementation in real scenarios.

Modification of Single Cells Within Mouse Mammary Gland Derived Acini via Viral Transduction.

The growth of organoid cultures from primary donor tissue is able to recapitulate the original tissue morphology, heterogeneity, and characteristics. Close study of these cultures grants a deeper understanding of the chain of events occurring during disease progression and healthy tissue development. While patient derived organoids are particularly suited to assay for novel treatment options, organoids obtained from model organisms are perfectly suited to establish in-depth analysis technology, including longitudinal imaging approaches, as well as proof of principle studies that rely on a steady source of primary tissue. All these approaches profit from advancements in technology to manipulate cells within an organoid.Here we present an optimized protocol to generate, culture, and transduce 3D acini obtained from mouse primary mammary epithelial cells via viral vectors. Applying this method, a few cells within the preserved organoid can be marked, changed, and tracked within an unaltered neighboring environment of non-transduced cells to better understand processes like, for instance, tumor initiation.

Experimental investigation on the thermal performance of a heat sink filled with PCM

Electronic devices and technologies have been revolutionized to meet future needs and users demands in terms of size, cost, and performance. Therefore, miniaturized devices have been of great interest and under investigation for the last decade. This demand requires attaining no less performance than achieved with large scale devices and designs. Hence, it becomes crucial to improve performance through changing physical design and/or utilized materials such as using composites or phase change material (PCM). In this study, two designs for heat sinks in the form of plates were created. The first was solid, whereas the second was hollow and contained PCM. Both of them were subjected to the same experiment conditions. The goal of the research is to figure out the overall temperature accomplished of both samples and to determine the impact of adding PCM to heat sinks thermal performance. The general design methodology for the heat sink is as follow: a steady heat source is applied to the plate fin heat sink's base. The plate heat sink's thermal efficiency was compared with and without the use of PCM. The results revealed that including PCM into the heat sink plate improves cooling and maintains the target temperature. Furthermore, the heat sink with a PCM outperformed by 30% compared to heat sink without PCM.

Fringe banking and financialization: Pawnbroking in pre‐famine and famine Ireland

AbstractPawnbroking, one of the oldest and most accessible forms of credit, was a common feature of life in pre‐famine and famine Ireland. This article studies the role of pawnbroking in the Irish financial system during this important period, applying insights from modern studies on fringe banking. In the period under study, a formal tiered financial system existed; regulated joint‐stock banks offered services to industry and the better off, while fringe banks provided financial services largely, but not exclusively, to unbanked groups. The main findings are that pawnbrokers provided a steady source of credit throughout the island of Ireland and that this credit stream was more durable than that provided by alternative financial service providers in the fringe banking market, especially during the famine. Our findings suggest a nuanced interpretation is needed as we find strong interrelationships between the various financial service providers.

The Search for Ultra-High Energy Neutrinos through Highly Inclined Air Showers in the Pierre Auger Observatory

The Surface Detector of the Pierre Auger Observatory for the detection of ultra-high energy cosmic rays, an array of 1600 water-Cherenkov stations in a triangular grid with 1500 m separation between stations, has also the capability to detect neutrinos with energy above 1017eV. The identification, through the special characteristics of highly inclined showers, is efficiently performed for neutrinos of all flavours interacting deep in the atmosphere at large zenith angles as well as for τ-neutrinos skimming the Earth crust. In this talk I review the status of the neutrino search at the Observatory using about 15 years of data. Restrictive upper bounds on the neutrino flux from diffuse sources and from point-like steady sources were stablished, placing strong constraints on several models of neutrino production at EeV energies and on the properties of the sources of ultra-high-energy cosmic rays. Unrivaled sensitivity in searches for transient sources has been also achieved.

Implications of the lowest frequency detection of the persistent counterpart of FRB121102

Context. The repeating FRB121102 is so far the only extragalactic fast radio burst found to be associated with a counterpart, that is to say a steady radio source with a nearly flat spectral energy distribution (SED) in centimeter wavelengths. Aims. Previous observations of the persistent source down to 1.6 GHz have not provided a sign of a spectral turnover. Absorption is expected to eventually cause a turnover at lower frequencies. Better constraints on the physical parameters of the emitting medium can be derived by detecting the self-absorption frequency. Methods. We used the Giant Metre-Wave Radio Telescope during the period of July to December 2017 to observe the source at low radio frequencies down to 400 MHz. Results. The spectral energy distribution of the source remains optically thin even at 400 MHz, with a spectral index of ν−(0.07 ± 0.03), which is similar to what is seen in Galactic plerions. Using a generic synchrotron radiation model, we obtain constraints on properties of the nonthermal plasma and the central engine powering it. Conclusions. We present low frequency detections of the persistent source associated with FRB121102. Its characteristic flat SED extends down to 400 MHz. Similar to models for Galactic plerions, we assume that the energy in the persistent source is carried predominantly by leptons. The emitting plasma has a B < 0.01 G, and its age is >524(B/0.01 G)−3/2 yr. We show that the energetics of the persistent source requires an initial spin period shorter than 36 ms, and the magnetic field of the neutron star must exceed 4.5 × 1012 G. This implies that the persistent source does not necessarily require energetic input from a magnetar.

Effects evaluation of fin layouts on charging performance of shell-and-tube LTES under fluctuating heat sources

The previous studies focus on the heat storage process of shell-and-tube latent thermal energy storage (LTES) under steady heat sources, without considering the fluctuating and intermittent characteristics of the most available heat sources in real applications. The effect of different fin sizes and locations on the charging performance of shell-and-tube LTES still keeps unclear under fluctuating heat source, and it is critical to improve the heat storage rate and density due to the low thermal conductivity of phase change materials (PCM). Consequently, this study aims to investigate the charging performance of a shell-and-tube LTES considering different fin layouts. Firstly, the effects of different fin number and configurations on heat storage process are performed under fluctuating heat sources. The case with comprehensive performance of high melting rate and large heat storage capacity is obtained. Then the effects of critical parameters on the charging process, including the fin angle, fin thickness, fin height and deviation distance of tube under fluctuating heat sources are further analyzed based on this case, and the results are compared with that of steady heat source. Results indicate that the fin height is the dominant factor influencing the heat storage rate and density under both steady and fluctuating heat source conditions, while the total melting time is shorter and the heat storage capacity is smaller, and the heat storage capacity is less obvious with the variation of fin parameters under the fluctuating heat source. In addition, the effect of downward deviation distance of tube on heat storage capacity is much obvious under fluctuating heat source than that of steady heat source.

In situ oxidation of sulfide minerals supports widespread sulfate reducing bacteria in the deep subsurface of the Witwatersrand Basin (South Africa): Insights from multiple sulfur and oxygen isotopes

Dissolved sulfate is a crucial electron acceptor for the subsurface biosphere, particularly for the living microbial ecosystems in the long-isolated (on the order of millions to billions of years) deep subsurface fracture waters in Precambrian cratons, e.g., in the Witwatersrand Basin of the Kaapvaal Craton, South Africa. Aiming to understand the role of sulfate in the sustainability of the subsurface habitat and the spatial extent of the terrestrial subsurface biosphere, we carried out a basin-scale examination on the sources and producing mechanisms of dissolved sulfur (sulfate and sulfide) in the subsurface fracture waters in the Witwatersrand Basin using multiple sulfur isotopes (32,33,34,36S) and oxygen isotopes (16,18O). Dissolved sulfates in 14 fracture water samples collected from 900 to 3,413 meters below the surface at 6 sites show isotopic ranges from −5.3‰ to +19.4‰ for δ34S, −0.40‰ to +0.50‰ for Δ33S, and −1.1‰ to +10.9‰ for δ18O. These isotopic signatures are distinct to those of the sulfate minerals (e.g., the carbonate-associated sulfate in local Transvaal Supergroup dolomite sequences: δ34S = +31.4‰ to +39.2‰; Δ33S = −0.01‰ to +0.16‰), but identical to those of the sulfide minerals in the host rocks. This indicates that the dissolved sulfate in the fracture waters were dominantly generated by in situ oxidation of sulfide minerals at basin scale, although mixing of a small amount of surface sulfate at some sites cannot be completely ruled out. The dissolved sulfates in the less deep and less saline fracture waters are in oxygen isotope disequilibrium with their host waters, a surprising result given that the water residence times are orders of magnitude longer than the time required for oxygen isotope exchange to reach equilibrium. This implies that vigorous in situ sulfate production has occurred after the fracture waters were isolated. In contrast, the dissolved sulfate in the deeper, more saline waters are in apparent oxygen isotope equilibration or close to equilibration with their host waters. This might be attributed to a combined effect of faster oxygen isotope exchange between sulfate and water at higher temperatures, larger extent of sulfate reduction, and/or less efficient sulfate production. The dissolved sulfide in the fracture waters has similar Δ33S values but is 3.0‰ to 26.4‰ lower in δ34S than coexisting sulfate, suggesting that the dissolved sulfide is mostly generated from bacterial sulfate reduction, which is consistent with the widespread existence of sulfate-reducing bacteria down to >3.4 km below surface in the Witwatersrand Basin. Overall, these novel isotopic results demonstrate that geological processes can provide a steady long-term sulfate source in deep fracture fluids by in situ oxidation of sulfide minerals in their host rocks, and thereby a mechanism to sustain the terrestrial subsurface biosphere, even in deep, high-temperature, long-isolated water systems. Thus, sulfate as a terminal electron acceptor is not the limiting factor for the spatial expansion of terrestrial subsurface biosphere.

The Pd-catalyzed synthesis of difluoroethyl and difluorovinyl compounds with a chlorodifluoroethyl iodonium salt (CDFI)

Herein, we report a simple and efficient method for the direct installation of chlorodifluoroethyl group onto aromatic molecules of various aromatic amides with a new 2-chloro,2,2-difluoroethyl(mesityl)iodonium salt (CDFI). Moreover, the chlorodifluoroethyl compounds could be smoothly converted into difluorovinyl compounds in a one-pot or discrete procedure and regarded as a steady source of difluorovinyl compounds with “HCl-mask”.

Non-thermal Electron Energization During the Impulsive Phase of an X9.3 Flare Revealed by Insight-HXMT

Abstract The X9.3 flare SOL20170906T11:55 was observed by the CsI detector aboard the first Chinese X-ray observatory Hard X-ray Modulation telescope (Insight-HXMT). Using the wavelets method, we report 22 s quasiperiodic pulsations during the impulsive phase. The spectra from 100 keV to 800 keV show the evolution with the gamma-ray flux of a power-law photon index from ∼1.8 before the peak, ∼2.0 around the flare peak, to ∼1.8 again. The gyrosynchrotron microwave spectral analysis reveals a 36.″6 ± 0.″6 radius gyrosynchrotron source with mean transverse magnetic field around 608.2 Gauss. The penetrated ≥10 keV non-thermal electron density is about 106.7 cm−3 at peak time. The magnetic field strength followed the evolution of high-frequency radio flux. Further gyrosynchrotron source modeling analysis implies that there exists a quite steady gyrosynchrotron source, and the non-thermal electron density and transverse magnetic field evolution are similar to higher-frequency light curves. The temporal spectral analysis reveals that those non-thermal electrons are accelerated by repeated magnetic reconnection, likely from a lower corona source.

The Highly Self-absorbed Blazar PKS 1351-018

Abstract PKS 1351-018 at a redshift of z = 3.71 is one of the most luminous, steady synchrotron sources with a luminosity >1047 erg s−1. The synchrotron luminosity does not seem to have varied by more than ∼25% over 35 yr. In order to appreciate this remarkable behavior, if it were at z = 0.5, it would have a flux density at 15 GHz in a range of 110–137 Jy over 11 yr. In spite of this steady behavior, two strong γ-ray flares ≲1049 erg s−1 were detected in 2011 and 2016. There is a blazar-like behavior coexisting with the steady behavior. This study is aimed at elucidating the dual nature of this source. We find that the radio source is extremely compact with a bright core and a steep spectrum secondary component, 12 mas away, that appears to be constant in position and flux density in six epochs from 1995–2018. We estimate that a jet with a time averaged power of (5.2 ± 3.2) × 1045 erg s−1 terminates in this lobe, which is advancing ≳0.9c at a deprojected distance of 1–3 kpc from the central engine. This is the rare case of a young (∼6000 yr), very powerful radio source that is viewed a few degrees from the jet axis. We find evidence of a high velocity (4000 km s−1), high ionization wind emanating from a luminous quasar. The young radio jet appears to experience modest bending as it navigates through the intense quasar environment.