Large Signal Analysis of a New Meander Line Topology for W-band Traveling Wave Tubes

Satellite distribution of high data rate needs wide frequency band. The millimeter waves, in particular the W-band, provide wide bandwidth and relatively low attenuation. The link transmission power can be provided only by Traveling Wave Tubes (TWTs). A new meander line topology to be used as slow wave structure for 71-76 GHz TWTs, with improved performance in comparison to the conventional one, is proposed. The new meander line compared to a standard meander line shows flatter gain and higher output power. © 2019 IEEE

DENSITÉ DES NIVEAUX DE BASSE ÉNERGIE ET INSTABILITÉS DE SURFACE DANS LES NOYAUX LOURDS DE TRANSITION

Une analyse statistique des niveaux nucléaires de Au, Pt, Hg a été réalisée avec la méthode d'Ericson. Les distributions expérimentales du nombre de niveaux d'or impair sont comparées aux distributions théoriques correspondant aux modèles vibrationnels (Alaga, Kisslinger-Sorensen) et rotationnels (Stephens, Meyer-ter-Vehn). Le modèle d'Alaga donne la description la plus complète des niveaux de 193,195Au et s'accorde avec la partie inférieure de la distribution de haute énergie de Gilbert-Cameron (déduite du modèle statistique et des données de capture neutronique). La méthode d'Ericson révèle d'autres aspects intéressants des isotopes de Pt et Hg (p. ex. dépendance entre la densité des niveaux et la forme des noyaux ou des corrélations de paires, évidence pour des transitions de phase). En conséquence, cette méthode est un outil approprié pour l'orientation des recherches expérimentales aussi bien que théoriques des noyaux de transition

Mobile-Based Monitoring System Framework for Smart Hydroponics Lettuce Farming

Hydroponics farming is popular all over the world because it sustains many people who suffer from hunger and who don’t have a lot of space or land that can be planted. The focus of this study is to provide material and design for innovative smart hydroponics farming that involves growing a lettuce plant using IoT devices, sensors, and Node-Red. Conducting this study is critical to the research because different components need to be identified first, as well as features for mobile devices connected to the IoT devices. The aim of this study is to design an IoT-based system that constantly monitors the water level, temperature, and humidity of the hydroponic lettuce crop. To fulfill the aim of the study, the researchers provide material and design for how it works, methodology for the hardware of the system, and a design thinking process to address complex problems and come up with unique solutions that emphasize innovation. As a result, the study can collect data from the different sensors. The readings of the sensors can be accessed through the Node-red Dashboard, viewable on mobile devices. Additionally, the researchers suggested exploring more about Node-Red and other possible uses of it in the IoT

Scalar fields, bent branes, and RG flow

This work deals with braneworld scenarios driven by real scalar fields with standard dynamics. We show how the first-order formalism which exists in the case of four dimensional Minkowski space-time can be extended to de Sitter or anti-de Sitter geometry in the presence of several real scalar fields. We illustrate the results with some examples, and we take advantage of our findings to investigate renormalization group flow. We have found symmetric brane solutions with four-dimensional anti-de Sitter geometry whose holographically dual field theory exhibits a weakly coupled regime at high energy.Comment: 22 pages, 7 figure

Deforming tachyon kinks and tachyon potentials

In this paper we investigate deformation of tachyon potentials and tachyon kink solutions. We consider the deformation of a DBI type action with gauge and tachyon fields living on D1-brane and D3-brane world-volume. We deform tachyon potentials to get other consistent tachyon potentials by using properly a deformation function depending on the gauge field components. Resolutions of singular tachyon kinks via deformation and applications of deformed tachyon potentials to scalar cosmology scenario are discussed.Comment: To appear in JHEP, 19 pages, 5 eps figures, minor changes and one reference adde

Influence of natural deep eutectic systems in water thermal behavior and their applications in cryopreservation

Natural deep eutectic systems (NADES), which have applications as solvents for both engineering and life sci-ences, are mainly composed of sugars, aminoacids or organic acids. In this work NADES composed by glucose,urea and proline (G:U:P in a molar ratio of 1:1:1) and proline and glucose (P:G 5:3) were prepared and addedin different mass fractions to water.By differential scanning calorimetry it was verified as the crystallization tendency of water is modified even forlow fraction of NADES added. This is also observed by polarized optical microscopy which allowed followingthe formation of crystals with different crystalline morphologies as bulk water. Calorimetric data also shown asthe crystallization temperature decreases for all P:G mixtures and this shift is more accentuated for weight frac-tion of NADES higher than 0.5. Crystallization is totally suppressed for NADES fraction higher than 0.7.NADES/water mixtures cytotoxicity was evaluated in vitro, revealing that they are less toxic as compared withthe commonly used cryoprotective additives as dimethyl sulfoxide (DMSO). Additionally, cell viability testswith cell lines cryopreserved using DMSO and both the prepared NADES showed comparable viability.This work combines thermophysical data on NADES and evaluates itâ s in vitro performance, providing cues fortheir use in cryopreservation applications.European Union Horizon 2020 Program under the agreement number ERC-2016-CoG 725034 (ERC Consolidator Grant Des.solve). This research was also funded by PTDC/EQU-EQU/29851/2017. A. Paiva acknowledges the financial support from project IF/01146/2015 attributed within the 2015 FCT researcher program. This work was supported by the Associate Laboratory for Green Chemistry - LAQV which is financed by national funds from FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020

Prototype Using Ultrasonic Sensor to Assist Visually Impaired Individual in the Philippines

People who are visually impaired deals with number of difficulties when exercising the most basic things in daily life. Some are frequently rely on others, which makes them less confident in an unusual setting and some use tools like white cane or simple sticks, but for some cirsumstances these could put their lives at risk while traveling. Since the Philippines has limited access to technological resources that could reduce the risk, the researchers came up with the idea of using an ultrasonic sensor to detect obstacles that are above or in front of the user. The study aims to develop a functional prototype that helps visually impaired individual and determine how well the functional prototype responds to the needs of the blind individual. Utilizing a problem-based approach to problem solving, the Design Thinking Methodology was the methodology employed in this study. As a result, using different sound and vibration frequencies the prototype can identify minimum distances of 120 cm, 80 cm, and 30 cm as an output. The study concludes that a successful tool could be a design prototype that uses sensor-equipped sticks to assist blind individuals in moving around and increasing their awareness of their surroundings. However, the scope of this study is limited as it is unable to determine the material of the obstruction or whether a hole exists in front of the user because the tool used in this work can only detect barriers above and in front of the user