Selection of a starting system for a low cost single engine fighter aircraft

Switched reluctance motors (SRMs) are simple in structure, easy to manufacture, magnet-less, brushless, and highly robust compared to other AC motors which makes them a good option for applications that operate in harsh environment. However, the motor has non-linear magnetic characteristics, and it comes with various pole-phase combinations and circuit topologies that causes many difficulties in deciding on which type to choose. In this paper, the viability of SRM as a low-cost, rugged machine for vehicle radiator cooling fan is considered. First, necessary design considerations are presented, then three commonly use types of SRM are analyzed: A 3-phase 6/4, 3-phase 12/8, and a 4-phase 8/6 to find their static and dynamic characteristics so the most suitable type can be selected. Simulation results show that the 8/6 SRM produces the highest efficiency with less phase current which reduces the converter burden. However, with asymmetric half bridge converter, eight power switches are required for 8/6 SRM and thus put a burden on the overall drive cost. As a solution, the Miller converter with only six switches for four phase SRM. To verify the proposed idea, the 8/6 SRM was manufactured and tested. The results show that Miller converter can be used for the proposed SRM with slightly reduced efficiency at 80.4%.

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An IoT-Based Participatory Antitheft System for Public Safety Enhancement in Smart Cities

Smart Cities ◽

10.3390/smartcities4020047 ◽

2021 ◽

Vol 4 (2) ◽

pp. 919-937

Author(s):

Nikos Papadakis ◽

Nikos Koukoulas ◽

Ioannis Christakis ◽

Ilias Stavrakas ◽

Dionisis Kandris

Keyword(s):

Smart Cities ◽

Low Cost ◽

Negative Influence ◽

Asset Tracking ◽

Tracking Tasks ◽

Tracking Process ◽

The Impact ◽

Operation Center ◽

Safety Enhancement ◽

Selection Of

The risk of theft of goods is certainly an important source of negative influence in human psychology. This article focuses on the development of a scheme that, despite its low cost, acts as a smart antitheft system that achieves small property detection. Specifically, an Internet of Things (IoT)-based participatory platform was developed in order to allow asset-tracking tasks to be crowd-sourced to a community. Stolen objects are traced by using a prototype Bluetooth Low Energy (BLE)-based system, which sends signals, thus becoming a beacon. Once such an item (e.g., a bicycle) is stolen, the owner informs the authorities, which, in turn, broadcast an alert signal to activate the BLE sensor. To trace the asset with the antitheft tag, participants use their GPS-enabled smart phones to scan BLE tags through a specific smartphone client application and report the location of the asset to an operation center so that owners can locate their assets. A stolen item tracking simulator was created to support and optimize the aforementioned tracking process and to produce the best possible outcome, evaluating the impact of different parameters and strategies regarding the selection of how many and which users to activate when searching for a stolen item within a given area.

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Theoretical and Empirical Characterization of Water as a Factor: Examples and Related Issues with the World Trade Model

Water ◽

10.3390/w13040459 ◽

2021 ◽

Vol 13 (4) ◽

pp. 459

Author(s):

Ignacio Cazcarro ◽

Albert E. Steenge

Keyword(s):

World Trade ◽

Low Cost ◽

Virtual Water ◽

Considerable Change ◽

Water Research ◽

Trade Model ◽

The World ◽

Main Model ◽

Selection Of

This article originates from the theoretical and empirical characterization of factors in the World Trade Model (WTM). It first illustrates the usefulness of this type of model for water research to address policy questions related to virtual water trade, water constraints and water scarcity. It also illustrates the importance of certain key decisions regarding the heterogeneity of water and its relation to the technologies being employed and the prices obtained. With regard to WTM, the global economic input–output model in which multiple technologies can produce a “homogeneous output”, it was recently shown that two different mechanisms should be distinguished by which multiple technologies can arise, i.e., from “technology-specific” or from “shared” factors, which implies a mechanism-specific set of prices, quantities and rents. We discuss and extend these characterizations, notably in relation to the real-world characterization of water as a factor (for which we use the terms technology specific, fully shared and “mixed”). We propose that the presence of these separate mechanisms results in the models being sensitive to relatively small variations in specific numerical values. To address this sensitivity, we suggest a specific role for specific (sub)models or key choices to counter unrealistic model outcomes. To support our proposal we present a selection of simulations for aggregated world regions, and show how key results concerning quantities, prices and rents can be subject to considerable change depending on the precise definitions of resource endowments and the technology-specificity of the factors. For instance, depending on the adopted water heterogeneity level, outcomes can vary from relatively low-cost solutions to higher cost ones and can even reach infeasibility. In the main model discussed here (WTM) factor prices are exogenous, which also contributes to the overall numerical sensitivity of the model. All this affects to a large extent our interpretation of the water challenges, which preferably need to be assessed in integrated frameworks, to account for the main socioeconomic variables, technologies and resources.

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Physically Self-assembled Au Nanorod Arrays for SERS

MRS Proceedings ◽

10.1557/proc-0951-e09-35 ◽

2006 ◽

Vol 951 ◽

Cited By ~ 1

Author(s):

Motofumi Suzuki ◽

Kaoru Nakajima ◽

Kenji Kimura ◽

Takao Fukuoka ◽

Yasushige Mori

Keyword(s):

Raman Spectroscopy ◽

Low Cost ◽

Major Axis ◽

Surface Enhanced Raman Spectroscopy ◽

Nanorod Arrays ◽

Au Nanorods ◽

Surface Enhanced ◽

Surface Enhanced Raman ◽

Oblique Deposition ◽

Selection Of

ABSTRACTWe have demonstrated surface-enhanced Raman spectroscopy on arrays of Au nanorods aligned in line by a dynamic oblique deposition technique. For the light polarized along the major axis of the nanorods, the plasma resonance of the Au nanorods has been tuned to a wavelength suitable for Raman spectroscopy. The Raman scattering on the discrete nanorods is enhanced significantly compared with that on semi continuous Au films. Since the preparation process is physically bottom-up, it is robust in its selection of the materials and is useful in providing the SERS sensors at low cost.

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Improving quality of life for dialysis patients through telecare

Journal of Telemedicine and Telecare ◽

10.1258/1357633001934249 ◽

2000 ◽

Vol 6 (1_suppl) ◽

pp. 80-83 ◽

Cited By ~ 14

Author(s):

Karl A Stroetmann ◽

Peter Gruetzmacher ◽

Veli N Stroetmann

Keyword(s):

Quality Of Life ◽

Low Cost ◽

Video Communication ◽

Daily Routine ◽

Dialysis Patients ◽

Home Dialysis ◽

Service Support ◽

Initial Results ◽

Selection Of

Home dialysis can improve the care and quality of life for patients with renal failure. We have explored the possibility of extending home care to more patients needing continuous ambulatory peritoneal dialysis (CAPD) using telemedicine. We tested videoconferencing support for five CAPD patients using low-cost ISDN equipment (128 kbit/s). Initial results indicated that it was possible to integrate video-communication into the daily routine of the clinic and the response from patients was surprisingly positive. Selection of appropriate, affordable technology and the ISDN service support by the telecommunications provider proved to be considerably more difficult than anticipated. The first indications also suggest medical advantages for home teledialysis.

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An Analysis on the Forming Load of AA 2024 Aluminium Alloy in Combined and Sequence Operation Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.519-521.949 ◽

2006 ◽

Vol 519-521 ◽

pp. 949-954 ◽

Cited By ~ 4

Author(s):

Beong Bok Hwang ◽

J.H. Shim ◽

Jung Min Seo ◽

H.S. Koo ◽

J.H. Ok ◽

...

Keyword(s):

Finite Element ◽

Load Capacity ◽

Low Cost ◽

Forming Load ◽

Mechanical Press ◽

Combined Operation ◽

Aa 2024 ◽

Load Characteristics ◽

Simulation Results ◽

Selection Of

This paper is concerned with the analysis of the forming load characteristics of a forward-backward can extrusion in both combined and sequence operation. A commercially available finite element program, which is coded in the rigid-plastic finite element method, has been employed to investigate the forming load characteristics. AA 2024 aluminum alloy is selected as a model material. The analysis in the present study is extended to the selection of press frame capacity for producing efficiently final product at low cost. The possible extrusion processes to shape a forward-backward can component with different outer diameters are categorized to estimate quantitatively the force requirement for forming forward-backward can part, forming energy, and maximum pressure exerted on the die-material interfaces, respectively. The categorized processes are composed of combined and/or some basic extrusion processes such as sequence operation. Based on the simulation results about forming load characteristics, the frame capacity of a mechanical press of crank-drive type suitable for a selected process could be determined along with securing the load capacity and with considering productivity. In addition, it is suggested that different load capacities be selected for different dimensions of a part such as wall thickness in forward direction and etc. It is concluded quantitatively from the simulation results that the combined operation is superior to sequence operation in terms of relatively low forming load and thus it leads to low cost for forming equipments. However, it is also known from the simulation results that the precise control of dimensional accuracy is not so easy in combined operation. The results in this paper could be a good reference for analysis of forming process for complex parts and selection of proper frame capacity of a mechanical press to achieve low production cost and thus high productivity.

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From Coarse to Fine: An Augmented Reality Based Dynamic Inspection Method for Visualized Railway Routing of Freight Cars

Measurement Science and Technology ◽

10.1088/1361-6501/ac3c1c ◽

2021 ◽

Author(s):

Bing Yi ◽

Renkai Sun ◽

Long Liu ◽

Yongfeng Song ◽

Yinggui Zhang

Keyword(s):

Augmented Reality ◽

High Efficiency ◽

Low Cost ◽

Digital Data ◽

Route Selection ◽

Inspection Method ◽

Envelope Model ◽

Freight Car ◽

Cargo Transportation ◽

Selection Of

Abstract It is a challenge for the dynamic inspection of railway route for freight car transporting cargo that out-of-gauge. One possible way is using the inspection frame installed in the inspection train to simulate the whole procedure for cargo transportation, which costs a lot of manpower and material resources as well as time. To overcome the above problem, this paper proposes an augmented reality (AR) based dynamic inspection method for visualized railway routing of freight car with out-of-gauge. First, the envelope model of the dynamic moving train with out-of-gauge cargo is generated by using the orbital spectrum of the railway, and the envelope model is matched with a piece of homemade calibration equipment located on the position of the railway that needs to be inspected. Then, the structure from motion (SFM) algorithm is used to reconstruct the environment where the virtual envelope model occludes the buildings or equipment along the railway. Finally, the distance function is adopted to calculate the distance between the obstacle and the envelope of the freight car with out-of-gauge, determining whether the freight car can pass a certain line. The experimental results show that the proposed method performs well for the route selection of out-of-gauge cargo transportation with low cost, high precision, and high efficiency. Moreover, the digital data of the environments along the railway and the envelope of the freight car can be reused, which will increase the digitalization and intelligence for route selection of out-of-gauge cargo transportation.

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Modern nanobiotechnologies for efficient detection and remediation of mercury

Sensor Review ◽

10.1108/sr-12-2020-0290 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Mulayam Singh Gaur ◽

Rajni Yadav ◽

Mamta Kushwah ◽

Anna Nikolaevna Berlina

Keyword(s):

Heavy Metals ◽

Water Samples ◽

Low Cost ◽

High Sensitivity ◽

Environmental Water ◽

Mercury Ions ◽

Content Type ◽

Efficient Detection ◽

Sensitivity And Selectivity ◽

Selection Of

Purpose This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. Design/methodology/approach Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples. Findings This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples. Originality/value This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.

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Extending QGroundControl for Automated Mission Planning of UAVs

Sensors ◽

10.3390/s18072339 ◽

2018 ◽

Vol 18 (7) ◽

pp. 2339 ◽

Cited By ~ 8

Author(s):

Cristian Ramirez-Atencia ◽

David Camacho

Keyword(s):

Flight Control ◽

Low Cost ◽

Real Life ◽

Mission Planning ◽

Human Computer Interface ◽

Simulation Environment ◽

Test Bed ◽

Multiple Vehicles ◽

Operator Workload ◽

Selection Of

Unmanned Aerial Vehicles (UAVs) have become very popular in the last decade due to some advantages such as strong terrain adaptation, low cost, zero casualties, and so on. One of the most interesting advances in this field is the automation of mission planning (task allocation) and real-time replanning, which are highly useful to increase the autonomy of the vehicle and reduce the operator workload. These automated mission planning and replanning systems require a Human Computer Interface (HCI) that facilitates the visualization and selection of plans that will be executed by the vehicles. In addition, most missions should be assessed before their real-life execution. This paper extends QGroundControl, an open-source simulation environment for flight control of multiple vehicles, by adding a mission designer that permits the operator to build complex missions with tasks and other scenario items; an interface for automated mission planning and replanning, which works as a test bed for different algorithms, and a Decision Support System (DSS) that helps the operator in the selection of the plan. In this work, a complete guide of these systems and some practical use cases are provided

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A New Approach to Drug Discovery

CrossRef Listing of Deleted DOIs ◽

10.1177/1087057111433459 ◽

2012 ◽

Vol 17 (4) ◽

pp. 542-549 ◽

Cited By ~ 57

Author(s):

Maria Cândida Monteiro ◽

Mercedes de la Cruz ◽

Juan Cantizani ◽

Catalina Moreno ◽

José R. Tormo ◽

...

Keyword(s):

Drug Discovery ◽

Antifungal Activity ◽

High Throughput Screening ◽

Low Cost ◽

Pharmacological Action ◽

Natural Extracts ◽

Microbial Extracts ◽

Set Up ◽

Microtiter Assay ◽

Selection Of

Natural products are an inexhaustible source for drug discovery. However, the validation and selection of primary screening assays are vital to guarantee a selection of extracts or molecules with relevant pharmacological action and worthy of following up. The assay must be rapid, simple, easy to implement, and produce quick results and preferably at a low cost. In this work, we developed and validated a colorimetric microtiter assay using the resazurin viability dye. The parameters of the resazurin method for high-throughput screening (HTS) using natural extracts against Aspergillus fumigatus were optimized and set up. The extracts plus RPMI-1640 modified medium containing the spores and 0.002% resazurin were added per well. The fluorescence was read after 24 to 30 h of incubation. The resazurin proved to be as suitable as Alamar Blue for determining the minimal inhibitory concentration of different antifungals against A. fumigatus and effective to analyze fungicidal and fungistatic compounds. An HTS of 12 000 microbial extracts was carried out against two A. fumigatus strains, and 2.7% of the extracts displayed antifungal activity. Our group has been the first to use this methodology for screening a collection of natural extracts to identify compounds with antifungal activity against the medically important human pathogen A. fumigatus.

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