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Letter from A.L. Monmerqué de Courmont.
No full textLetter from A.L. Monmerqué de Courmont, possibly Adélaïde Louise de Monmerqué (1767-1835) who had been married to Louis Marie Le Bas de Courmont (1741-1794), dated 10 pluvoise. It is not addressed but was presumably sent to Philippe-Antoine Merlin, as it comprises the verso of one of his requisitions from 1802. In this letter the author requests a day and an hour when she (or he) might meet with the recipient
Radio frequency energy harvesting and low power data transmission for autonomous wireless sensor nodes
No full textSince the Internet of Things (IoT) is expected to be the new technology to drive the semiconductor industry, significant research efforts have been made to develop new circuit and system techniques for autonomous/very low-power operation of wireless sensor nodes. Very low-power consumption of sensors is key to increase battery lifetime or allow for battery-less (autonomous) operation of sensors, which contributes to preventing or reducing the high maintenance costs of battery supplied sensors and reduce the amount of discarded batteries.This thesis, entitled Radio Frequency Energy Harvesting and Low Power Data Transmission for Autonomous Wireless Sensor Nodes, presents very low-power consumption circuit and system techniques combined with energy harvesting that allow the creation of autonomous wireless sensor nodes. This work focuses on three main challenges: 1) how to improve energy harvesting efficiency, 2) how to minimize power consumption of data transmission and 3) how to combine low-power techniques and energy harvesting in a system. These challenges are addressed in this thesis with on-PCB and Integrated Circuits (IC) solutions.The efficiency of radio frequency (RF) energy harvesting is improved by proposing a new topology of a charge-pump rectifier. The proposed topology uses a voltage boosting network to compensate for the voltage drop in the transistors. The new topology is presented and analyzed. Simulation results are compared to the analytical analysis and measurement results of the circuit that has been fabricated in a 0.18um CMOS technology and operates at 13.53 MHz.Although the efficiency of RF energy harvesting is improved using the above technique, at the same time, low power techniques in data transmission should be developed to save energy. Pulse width modulation and impulse transmission techniques to minimize power consumption have been developed and are presented in this thesis.The developed pulse modulation circuitry has been fabricated in 0.18um CMOS technology as part of a System on Chip (SoC). The new impulse transmitter topology for low-voltage low-power operation has been fabricated on PCB with micro-wave discrete components. Theoretical analysis, simulations and measurements results are shown to prove the impulse transmitter concept.The circuits developed are integrated in a SoC with energy harvesting to prove the concept of autonomous wireless sensor nodes. Two sensor nodes have been designed and measured: one for autonomous temperature monitoring and the second for autonomous ECG monitoring. Both designs operate from wireless power without the use of batteries. Finally, the work developed in this thesis is summarized and future research possibilities are discussed
Mind the Gap: Designing Sustainable Healthcare for Humanitarian Aid
No full textHumanitarian emergencies like the natural disasters in Nepal, Haiti or Pakistan or the thousands of refugees and internally displaced people fleeing from long-term conflict in Syria or South Sudan are likely to increase. To provide healthcare assistance, international humanitarian organizations transfer a variety of medical equipment and staff to an affected area with the purpose of reinforcing or even replacing disrupted healthcare activities. The replacement system they transfer is usually of a high quality standard, and therefore not suitable to be transported, used, maintained and disposed in austere and low-resource settings. In comparison to providing food or shelter assistance, providing safe healthcare in such situations is particularly challenging due to the level of medical and technical expertise required. In this thesis, the unsustainability of the transfer process of medical equipment in humanitarian emergencies is addressed by describing and analysing how the transfer takes place. Furthermore, two field studies in Indonesia and Haiti are presented. The humanitarian sector is increasingly challenged by the need to become more efficient and competitive. The recent adoption of the ‘humanitarian innovation’ concept, defined by words like “sustainable”, “beneficiaries”, and “long-term” brings an encouraging view ahead towards a more sustainable transfer of medical equipment. A combination of field, interview and literature studies, led to the development of a systems design approach to the transfer of medical equipment in humanitarian emergencies that challenges the field of medical design engineering to broaden its scope and disciplinary boundaries.Design EngineeringIndustrial Design Engineerin
Systems design perspective of healthcare provision in humanitarian aid
No full textThis study focuses on the role of Systems Design in addressing the challenges of healthcare provision by international emergency relief organizations in developing countries. More specifically the challenges related to the safety and performance of medical equipment that is transferred in the aftermath of a humanitarian crisis. The aim of this paper is to describe the transfer of medical equipment and its associated challenges from a systems perspective and to reflect on the value of Systems Design as an approach to humanitarian innovation, addressing the identified systemic challenges. The concepts of Human Factors and Ergonomics, and Product-Service Systems will be presented as valuable contributions to support designers in handling a larger degree of complexity throughout the design process and to support them to make informed choices regarding this particular context.neoDesign for SustainabilityMedical Instruments & Bio-Inspired Technolog
S.L.I.M., a small linear interdependent model of eight EU-member states, the USA and Japan
No full textInternational Economics;EU
A Review of Some Updates in the 13th Edition of “Sears and Zemansky’s University Physics with Modern Physics” (Authors: Hugh D. Young and Roger A. Freedman; contributing author, A. Lewis Ford; 2012)
No full textYoung, H.D.; and Freedman, R.A.; Ford, A.L. (contributing author). 2012. Sears and Zemansky’s University Physics with Modern Physics. 13th ed.Pearson Education, Inc., Addison-Wesley, San Francisco, CA, USA
Absorption refrigeration machines: Theoretical and experimental assessment of the performance of aqua-ammonia absorption machines operated at marginal conditions, e.g. when powered by solar or waste heat. Development of a new type of absorber.
No full textMechanical, Maritime and Materials EngineeringMechanical, Maritime and Materials Engineerin
Development of an advanced absorption heat transformer
No full textMechanical Maritime and Materials Engineerin
Thermal energy storage by means of an absorption cycle
No full textMechanical Maritime and Materials Engineerin
Modelling of a refrigerating system coupled with a refridgerated room
No full textMechanical Maritime and Materials Engineerin
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