Progress on modeling and design of membrane reactors for hydrogen production

This paper presents an overview of recent research carried out by the authors on the development and analysis of mathematical models describing hydrogen production in membrane reactors. The case considered is that of methane steam reforming (SR) in a reactor with the typical double pipe configuration, in which a hydrogen-permeable membrane is present on the outer wall of the innermost tube. The model developed accounts for the rate of reaction, convective and dispersive transport in the axial and radial directions, and hydrogen permeation across the membrane. Density variations with pressure and gas composition have been accounted for, leading to a full coupling of mass and momentum transport. Different geometric aspect ratios have also been studied to assess the influence of catalyst volume on the overall performance of the system. The presence of two distinct transport regimes, in which hydrogen permeation is limited either by transport within the packed bed or permeation across the membrane, has been identified, along with the operating conditions that determine their range of existence. This has allowed the development of a simplified model, valid under the hypothesis that the reaction is fast compared to transport. In the permeation-controlled regime, the permeate flow rate and recovery may be found by solving a set of two PDEs, whereas an analytical solution is available for the transport-controlled regime. The main steps and observations that have brought to the development of the simplified model are presented, along with a guide to its implementatio

Three-meter balloon-borne telescope

The Three-Meter Balloon-Borne Telescope is planned as a general purpose facility for making far-infrared and submillimeter astronomical observations from the stratosphere. It will operate throughout the spectral range 30 microns to 1 millimeter which is largely obscurred from the ground. The design is an f/13.5 Cassegrain telescope with an f/1.33 3-meter primary mirror supported with a 3-axis gimbal and stabilization system. The overall structure is 8.0 m high by 5.5 m in width by 4.0 m in depth and weighs 2000 kg. This low weight is achieved through the use of an ultra lightweight primary mirror of composite construction. Pointing and stabilization are achieved with television monitoring of the star field, flex-pivot bearing supports, gyroscopes, and magnetically levitated reaction wheels. Two instruments will be carried on each flight; generally a photometric camera and a spectrometer. A 64-element bolometer array photometric camera operating from 30 to 300 microns is planned as part of the facility. Additional instruments will be derived from KAO and other development programs

The Development of an Assault Directed Infrared Countermeasures (DIRCM) Program

The purpose of this thesis is to document the history of the development of an Assault Directed Infrared Countermeasures (DIRCM) Program as well as Navy Program Office (PMA272) efforts to date, to initiate a new start ACAT II Program for Navy and Marine Corps helicopters starting in Fiscal Year (FY) 2006. It concentrates on the programmatic aspects of Assault DIRCM and does not go into detail on the design or technical aspects of the development of the system. This thesis will introduce emerging threats to helicopters operating in theater and describe the requirement for a DIRCM technology. It will also highlight program issues based on observations made over the past year as well as provide a recommended path forward for immediate program execution considering internal and external program and acquisition constraints both real and perceived

UTILIZING THE MIT APP INVENTOR TOOLS AS A LEARNING MEDIA INFORMATION TO CREATE ANDROID-BASED APPLICATIONS

The rapid development of digital technology currently provides many benefits to humans. For example, the development of software or various technological tools that support activities and provide convenience in human life. With the development of the times, software is increasingly sophisticated in various fields, one of which is the field of education. In supporting the learning process, the education sector must follow and adapt existing technology. As is the case with learning media that currently uses an Android-based operating system. Therefore, it is very necessary to educate and teach how to build applications using the operating system. Based on the current problems, the authors provide an educational solution with "Utilization of MIT App Inventor Tools as Learning Media for Creating Android-Based Applications". The data collection technique in this study is a systematic analysis of observations by looking for document similarities. Data collection was also carried out through a literature review by looking for references, journals and documents related to this research. With current technological developments, educational institutions, especially universities, use a lot Android as a means of learning media. As a user of Android, Higher Education also has innovations in studying the provision of materials such as creating various Android-based applications, one of which is the MIT App Inventor. Based on the research process carried out, it can be concluded four things, namely MIT App Inventor is an alternative tool for creating Android-based applications, MIT App Inventor has a visual interface that is easier for ordinary people to learn to use, Visual design in making programs using the method drag-and-drop components, and tools MIT App Inventor also works fine

APLIKASI PENGOLAHAN DATA PEGAWAI PADA BADAN KEPEGAWAIAN DAERAH PROVINSI SUMATERA SELATAN

The purpose of this final report is to make an application on a data processing employee staffing agency of the Province of South Sumatra. Data collection methods in use is the primary observations (observation and interviews) observation study sekuder is literal. This Application Development Using the Ubuntu operating system and programming languages PHP MySQL database. System development model is applied in this application is Wartelfall. This application contains a login, form data input, form of employee data, form view data

Expert Systems For Sustainable Fibre Processing - A New Approach Through Machine Learning

The consequences of the climate crisis are driving an increase in demand for more sustainable fibre materials. The textile industry is experiencing a demand for more sustainable fibre materials as a market pull, whereas a significant technology push for processing these fibres is not yet visible. Traditionally, operators were tasked with the processing of common materials (e.g. cotton) and compensating for changes in their batch properties. Consequently, operators have not been trained to process non-conventional fibre materials. Consequently, the optimal settings for processing these materials are not included in the operator’s personal experience. This experience typically encompasses the state-of-the-art range of operating settings. These typically comprise the alteration of three to four main settings. To address these issues, an expert system for processing innovative fibre materials is developed within the scope of the ITA SmartMill. The SmartMill will combine expert knowledge and data collected from processing fibre materials through the utilisation of machine learning approaches. The final result will be an expert system that provides recommendations and enables operators to derive trends, thereby supporting the exploration of new operating ranges. In this paper, the development of a guideline for the formalised documentation of the processing of fibre materials is proposed. By following the guideline, a database containing important properties and processing data of very different fibres is created. Based on this work, an algorithm will be selected so that the expert system will be able to assist the operator in setting up the processes with recommendations based on the database and historical observations

The Autonomous System Architecture of the Small SAR Satellite Operation System and On-Orbit Autonomous Operation Experiences

We are developing a small SAR (Synthetic Aperture Radar) satellite for our commercial solution business. Our goal is to deploy at least 30 small SAR satellites in orbit and enable frequent and persistent observations until the Mid 2020s. We launched the satellite on 15th December 2020 by Rocket Lab\u27s Electron. We waited for a month until we took the first image to confirm the complete evacuation of the residual air and contaminations to prevent any hazardous electrical discharge. We took the first image on 8th February. The satellite is now operating in a fine state and acquiring images requested by the customers. We will make six satellite constellation until 2023. We also describe our system architecture including our solution business and the satellite development. Our business development team and the satellite development team are communicating with each other for adequate system architecture and agile satellite development. Our business development team acquires many novel needs from our customers. One of our goals is an agile reflection of the user\u27s needs for the satellite development. We are now establishing a process and an organization to extract those business needs, analyze them and identify the key requirements for the satellite performances and functions. We believe that one important challenge is to achieve application layer integration from a customer business system to a satellite on-board software through solution platform, data platform, satellite control ground system, and the satellite itself. We try to harmonize the software and information processes of the application layer, although the platform where the application is located, the organization where staffs belong, and their culture are different. We wish our activities contribute to our small satellite community or ecosystem and a system architecture including component suppliers, communication service providers, and data processing service providers

Towards nowcasting in Europe in 2030

The increasing impact of severe weather over Europe on lives and weathersensitive economies can be mitigated by accurate 0–6 h forecasts (nowcasts), supporting a vital ‘last line of defence’ for civil protection and many other applications. Recognizing lack of skill in some complex situations, often at convective and local sub-kilometre scales and associated with rare events, we identify seven recommendations with the aim to improve nowcasting in Europe by the national meteorological and hydrological services (NMHSs) by 2030. These recommendations are based on a review of user needs, the state of the observing system, techniques based on observations and high-resolution numerical weather models, as well as tools, data and infrastructure supporting the nowcasting community in Europe. Denser and more accurate observations are necessary particularly in the boundary layer to better characterize the ingredients of severe storms. A key driver for improvement is next-generation European satellite data becoming available as of 2023. Seamless ensemble prediction methods to produce enhanced weather forecasts with 0–24 h lead times and probabilistic products require further development. Such products need to be understood and interpreted by skilled forecasters operating in an evolving forecasting context

First M87 Event Horizon Telescope Results. II. Array and Instrumentation

The Event Horizon Telescope (EHT) is a very long baseline interferometry (VLBI) array that comprises millimeter- and submillimeter-wavelength telescopes separated by distances comparable to the diameter of the Earth. At a nominal operating wavelength of ~1.3 mm, EHT angular resolution (λ/D) is ~25 μas, which is sufficient to resolve nearby supermassive black hole candidates on spatial and temporal scales that correspond to their event horizons. With this capability, the EHT scientific goals are to probe general relativistic effects in the strong-field regime and to study accretion and relativistic jet formation near the black hole boundary. In this Letter we describe the system design of the EHT, detail the technology and instrumentation that enable observations, and provide measures of its performance. Meeting the EHT science objectives has required several key developments that have facilitated the robust extension of the VLBI technique to EHT observing wavelengths and the production of instrumentation that can be deployed on a heterogeneous array of existing telescopes and facilities. To meet sensitivity requirements, high-bandwidth digital systems were developed that process data at rates of 64 gigabit s^(−1), exceeding those of currently operating cm-wavelength VLBI arrays by more than an order of magnitude. Associated improvements include the development of phasing systems at array facilities, new receiver installation at several sites, and the deployment of hydrogen maser frequency standards to ensure coherent data capture across the array. These efforts led to the coordination and execution of the first Global EHT observations in 2017 April, and to event-horizon-scale imaging of the supermassive black hole candidate in M87