Abstract: A dual-hop system for optical wireless communication between a base station on Earth and satellite is described. The system includes a first Thulium-Doped Fiber Amplifier (TDFA) at the base station and a second TDFS installed in a High-Altitude Platform Station (HAPS). The first TDF A includes a first thulium-doped fiber (TDF) and a first set of optical pumps. The first TDFA amplifies an input optical signal for wireless transmission to the HAPS installed at a specific altitude. The amplified signal is received by the second TDFA at HAPS. The second TDFA includes a second TDF and a second set of optical pumps. The signal amplified by the second TDFA is compensated for attenuation before it is wirelessly transmitted to the satellite. Both TDFAs ensure that the amplification of the optical signals, either through power amplification or gain, meets specified criteria to maintain the integrity and quality of the transmitted signals.

Abstract: A field portable device for determining the unconfined compressive strength of a soil sample includes a sample holder, a heating device, a scale, a spectrometer, and a microprocessor. The sample holder receives a soil sample. The heating device dries the soil sample for a specified time. The scale measures a weight of the soil sample and a dried weight of the soil sample. The spectrometer performs laser induced breakdown spectroscopy on the soil sample and generates spectral emission intensities of the soil sample. The microprocessor calculates a bulk density and a water content of the soil sample, actuates the spectrometer to generate the spectral emission intensities. The microprocessor applies the spectral emission intensities, the bulk density and the water content to a trained machine learning regressor combined with an adaptive boosting classifier to predict the unconfined compressive strength of the soil sample.

Abstract: A three element slot-based antenna which includes a dielectric circuit board, a metallic layer, a sensing antenna, a first narrow band antenna, a second narrow band antenna, a first tapered transmission line, a second tapered transmission line, a first microstrip transmission line and a second microstrip transmission line. The sensing antenna is a semi-hexagonal slot-line loop whereas each of the first narrow band antenna and the second narrow band antenna are formed as a semi-elliptical slot-line loop having an E-shaped base in the metallic layer. The first tapered transmission line and the second tapered transmission line is connected to first feed port and second feed port, respectively. The first microstrip transmission line and the second microstrip transmission line are connected to third feed port and fourth feed port, respectively. The antenna resonates with circular polarization in an ultra-high frequency sub-GHz responsive to input signal at each feed port.

Abstract: Carbon nanofiber doped alumina (Al-CNF) supported MoCo catalysts in hydrodesulfurization (HDS), and/or boron doping, e.g., up to 5 wt % of total catalyst weight, can improve catalytic efficiency. Al-CNF-supported MoCo catalysts, (Al-CNF-MoCo), can reduce the sulfur concentration in fuel, esp. liquid fuel, to below the required limit in a 6 h reaction time. Thus, Al-CNF-MoCo has a higher catalytic activity than Al—MoCo, which may be explained by higher mesoporous surface area and better dispersion of MoCo metals on the AlCNF support relative to alumina support. The BET surface area of Al—MoCo may be 75% less than Al-CNF-MoCo, e.g., 166 vs. 200 m2/g. SEM images indicate that the catalyst nanoparticles can be evenly distributed on the surface of the CNF. The surface area of the AlMoCoB5% may be 206 m2/g, which is higher than AlMoCoB0% and AlMoCoB2%, and AlMoCoB5% has the highest HDS activity, removing more than 98% sulfur and below allowed levels.

Abstract: Carbon nanofiber doped alumina (Al—CNF) supported MoCo catalysts in hydrodesulfurization (HDS), and/or boron doping, e.g., up to 5 wt % of total catalyst weight, can improve catalytic efficiency. Al—CNF-supported MoCo catalysts, (Al—CNF—MoCo), can reduce the sulfur concentration in fuel, esp. liquid fuel, to below the required limit in a 6 h reaction time. Thus, Al—CNF—MoCo has a higher catalytic activity than Al—MoCo, which may be explained by higher mesoporous surface area and better dispersion of MoCo metals on the AlCNF support relative to alumina support. The BET surface area of Al—MoCo may be 75% less than Al—CNF—MoCo, e.g., 166 vs. 200 m2/g. SEM images indicate that the catalyst nanoparticles can be evenly distributed on the surface of the CNF. The surface area of the AlMoCoB5% may be 206 m2/g, which is higher than AlMoCoB0% and AlMoCoB2%, and AlMoCoB5% has the highest HDS activity, removing more than 98% sulfur and below allowed levels.

Abstract: Disclosed is a composition for a Controlled Low Strength Material (CLSM) including cementitious materials, water, and fine aggregate. The cementitious materials include powdered basaltic lava and Ordinary Portland Cement (OPC). In the composition, the basaltic lava replaces some of the ordinary Portland cement in the CLSM as compared to a conventional CLSM. The basaltic lava replaces 25% to 90% of the OPC in a conventional CLSM. The CLSM can be used as a compacted fill for structural and non-structural construction applications.

Abstract: A method of removing hydrogen sulfide from a subterranean geological formation includes injecting a drilling fluid suspension in the subterranean geological formation. The drilling fluid suspension has a pH of 10 or more and includes a layered triple hydroxide material, including manganese, cobalt, and iron, in an amount of 0.01 to 0.5 percent by weight of the drilling fluid suspension. The method further includes circulating the drilling fluid suspension in the subterranean geological formation and forming a water-based mud and scavenging the hydrogen sulfide from the subterranean geological formation by reacting the hydrogen sulfide with the layered triple hydroxide material in the water-based mud.

Abstract: A zero liquid brine desalination and crystallization system includes a humidification dehumidification (HDH) desalination system and includes a crystallization system. The HDH system includes a humidifier configured to humidify a carrier gas using saline water, and a dehumidifier configured to dehumidify the carrier gas to obtain desalinated water. The crystallization system is configured to receive the saline water from the HDH desalination system and includes an evaporation chamber configured to produce salt crystals and water vapor from the saline water, and a condenser configured to condense the water vapor. Herein, the HDH desalination system and the crystallization system are connected at the condenser for heat exchange between the water vapor and at least one selected from the group consisting of the saline water and the carrier gas.

Abstract: A dendrimeric carbon dot-polyamide membrane, a method for making the dendrimeric carbon dot-polyamide membrane, and a method for producing purified water are provided. An exemplary carbon dot-polyamide membrane includes polyamidoamine dendrimeric carbon dots and a polyamide membrane. The polyamidoamine dendrimeric dots are dispersed throughout the polyamide membrane.

Abstract: A method includes mixing a dopant salt of at least one of cobalt, nickel, zinc, and scandium with a silicate, in a solvent, to form a first solution. The method includes mixing the first solution with a solvent mixture to form a second solution. The method further includes mixing the second solution with an acid to form an acid solution. The method further includes adding a catalyst and a polymer to the acid solution to form the doped PCM. The doped PCM includes the catalyst, the polymer, at least one of cobalt, nickel, zinc, and scandium, and SiO2.

Abstract: A four element folded slot-based multiple-input-multiple-output (MIMO) antenna for use with CubeSats is described. The MIMO antenna includes a dielectric circuit board, and a metallic layer that covers a top side of the dielectric circuit board and covers a first portion and a second portion of a bottom side. A first meandering slot wraps from the top side, over the first edge and into the first portion on the bottom side. A second meandering slot wraps from the top side, over the second edge and into the second portion of the bottom side. A first feed horn is directed towards the first meandering slot. A second feed horn is directed towards the second meandering slot. A first capacitor is connected to the metallic layer across a slot section of the first meandering slot. A second capacitor connected to the metallic layer across a slot section of the second meandering slot.

Abstract: Carbon nanofiber doped alumina (Al—CNF) supported MoCo catalysts in hydrodesulfurization (HDS), and/or boron doping, e.g., up to 5 wt % of total catalyst weight, can improve catalytic efficiency. Al—CNF-supported MoCo catalysts, (Al—CNF—MoCo), can reduce the sulfur concentration in fuel, esp. liquid fuel, to below the required limit in a 6 h reaction time. Thus, Al—CNF—MoCo has a higher catalytic activity than Al—MoCo, which may be explained by higher mesoporous surface area and better dispersion of MoCo metals on the AlCNF support relative to alumina support. The BET surface area of Al—MoCo may be 75% less than Al—CNF—MoCo, e.g., 166 vs. 200 m2/g. SEM images indicate that the catalyst nanoparticles can be evenly distributed on the surface of the CNF. The surface area of the AlMoCoB 5% may be 206 m2/g, which is higher than AlMoCoB 0% and AlMoCoB 2%, and AlMoCoB 5% has the highest HDS activity, removing more than 98% sulfur and below allowed levels.

Abstract: A hybrid Hidden Markov Model (HMM) and Machine Learning (ML) systems and apparatus for classification in the case of data instances with imbalanced class distribution, including a Hidden Markov Model for generating a log-likelihood score for each data instance. Implementations of the hybrid system and method detect fraudulent activity and classifies documents with accuracy that surpasses conventional classifiers. In one implementation, Hidden Markov Model (HMM) for generating a log-likelihood score based on an attribute value vector for a set of keyword features characterizing a Web page. In one implementation, the HMM generates a log-likelihood score based on an attribute value vector for page layout characterizing a document image. Resulting attribute value vectors are ranked and divided into bins grouped by log-likelihood scores within equal ranges. Various machine learning models are trained using the balanced vectors obtained by accumulating from all the bins of vectors.

Abstract: This disclosure represents an improved computer system and process to avoid the consequences of improper conversion of numbers and of rounding errors. This process makes the distinction between exact and inexact decimal floating-point numbers. If the result of a sequence of operation is exact, the user can trust that every decimal digit in the computed result is correct. On the other hand, if the input operands are inexact or the result cannot be computed exactly, a loss of significant digits occurs, and the user is warned of the loss. A novel representation is used for the inexact computed values. An estimate of the absolute error is also part of the representation.

Abstract: A hybrid Hidden Markov Model (HMM) and Machine Learning (ML) systems and apparatus for classification in the case of data instances with imbalanced class distribution, including a Hidden Markov Model for generating a log-likelihood score for each data instance. Implementations of the hybrid system and method detect fraudulent activity and classifies documents with accuracy that surpasses conventional classifiers. In one implementation, Hidden Markov Model (HMM) for generating a log-likelihood score based on an attribute value vector for a set of keyword features characterizing a Web page. In one implementation, the HMM generates a log-likelihood score based on an attribute value vector for page layout characterizing a document image. Resulting attribute value vectors are ranked and divided into bins grouped by log-likelihood scores within equal ranges. Various machine learning models are trained using the balanced vectors obtained by accumulating from all the bins of vectors.

Abstract: A method of prioritizing updates to third-party libraries for a mobile application includes obtaining a list of a plurality of third-party libraries used in the mobile application. The method further includes, for each third-party library of the plurality of third-party libraries, computing a set of third-party library metrics of a third-party library and computing a weight for each third-party library metric type of the set of third-party library metrics. The method further includes computing, for each third-party library of the plurality of third-party libraries, a ranking value of the third-party library using the set of third-party library metrics and the weights, and selecting, based on the ranking value of the plurality of third-party libraries, one or more third-party libraries to be updated.

Abstract: An electrode includes an electrically conductive substrate and a layer of a molybdenum-doped zinc/cobalt oxide (ZnCo2-xMoxO4). The surface of the electrically conductive substrate is at least partially covered by the layer of ZnCo2-xMoxO4, where x is a positive number equal to or less than about 0.1, and the layer of the ZnCo2-xMoxO4 includes spherical-shaped particles. The electrode has a Tafel slope from 75 millivolts per second (mV/s) to 115 mV/s, and a potential of 0.27 to 0.30 volts relative to the reversible hydrogen electrode (VRHE) at a current density of about 50 mA/cm2 for a duration of at least 40 hours.

Abstract: A system and method for routing Field Programmable Gate Arrays (FPGAs) includes an input device for acquiring a netlist with defined source, sink, and intermediate nodes, and processing circuitry that features a design router. The router leverages a negotiated-congestion routing component, which promotes the shared use and negotiation for intermediate nodes. The negotiation process employs a congestion cost based on several factors, including base, historical, and present usage costs, alongside node capacity. This system is characterized by a historical cost function focused on the base cost of nodes, favoring the use of those with costs below a specified threshold. A display device incorporated within the system allows for the continuous monitoring of the routing procedure and the efficiency of resource usage. The technology aims to streamline FPGA design by optimizing signal routing for performance and area efficiency.

Abstract: A sampler system for water contaminants. The sampler system includes an adsorptive sampler housed within a cylindrical enclosure, which has a top face, a bottom face and a cylindrical surface. The cylindrical surface of the sampler system is fluid-permeable. A cable connects the top face of the cylindrical enclosure to a flotation device. A spring connects the adsorptive sampler to the bottom face of the cylindrical enclosure. The adsorptive sampler includes a housing having a cavity and an adsorptive material disposed inside the cavity. The housing is attached to the spring and includes a front face and a back face. The spring is a cantilever in the form of a rigid film, wherein the rigid film is connected to the bottom face of the cylindrical enclosure along a flat edge of the rigid film.

Abstract: This disclosure presents methods and systems of controlling a counter flow double pipe heat exchanger (DPHE) that includes a hot fluid pipe and a cold fluid pipe. In a method, a temperature error between a reference temperature and a temperature at an outlet of the hot fluid pipe of the counter flow DPHE is determined. A cold fluid mass flow rate is determined from an output of a proportional-integral-derivative (PID) controller based on the temperature error being input to the PID controller. The cold fluid mass flow rate is used for a cold fluid in the cold fluid pipe of the counter flow DPHE. The temperature error is controlled within a predefined range by utilizing parameters of the PID controller that are set by using a harmony search algorithm (HSA) to obtain a minimization of a cost function.