Examining Thermal Management Strategies for a Microcombustion Power Device

Microcombustion attracts interest with its promise of energy dense power generation for electronics. Yet, challenges remain to develop this technology further. Thermal management of heat losses is a known hurdle. Simultaneously, non-uniformities in heat release within the reaction regions also affect the device performance. Therefore a combination of thermal management strategies are necessary for further performance enhancements. Here, a bench top platinum nanoparticle based microcombustion reactor, coupled with thermoelectric generators is used. Methanol-air mixtures achieve room temperature ignition within a catalytic cartridge. In the current study, the reactor design is modified to incorporate two traditional thermal management strategies. By limiting enthalpic losses through the exhaust and reactor sides, using multi-pass preheating channels and heat recirculation, expected improvements are achieved. The combined strategies doubled the power output to 1.01 W when compared to the previous design. Furthermore, a preliminary study of catalyst distribution is presented to mitigate non-uniform catalytic activity within the substrate. To do this, tailored distribution of catalyst particles was investigated. This investigation shows a proof-of-concept to achieve localized control, thus management, over heat generation within substrates. By optimizing heat generation, a highly refined combustion-based portable power devices can be envisioned.

Exploring the meaning, role and experiences of a patient-led social innovation for people affected by cancer: a new collaborative care model complementing traditional cancer rehabilitation in Sweden

ObjectiveKraftens Hus is the first support centre in Sweden designed by and for people affected by cancer, including patients, family, friends, staff members and local community representatives (collectively ‘stakeholders’). The purpose of this study was to explore the meaning, role and experiences of Kraftens Hus stakeholders using a patient and public involved methodology.MethodsTo understand and map the experiences of visitors to Kraftens Hus, we applied concept mapping (CM), a mixed methods approach where data are collected and analysed in four structured steps designed to capture the diverse perspectives of multiple stakeholders. Qualitative interviews with relevant stakeholders supplemented the CM findings.ResultsThe final concept map contained six clusters of ideas. Within the clusters, there was a recurring theme that cancer-affected people value accessible and long-term psychosocial support (PSS). The intended emotional, social and practical needs identified in a previous design process seem to have been addressed and appreciated by Kraftens Hus visitors.ConclusionKraftens Hus is an example of a new patient-led social innovation based on a life-event perspective and integration of resources from different sectors in society. By focusing on life, not the disease, the care continuum expands, and long-term PSS is provided alongside cancer treatment. The evaluation confirms that PSS should focus on health and well-being in the broadest sense.

A DESIGN RATIONALE ANALYSIS METHOD TOWARDS ROBUST ARTIFACT DESIGN

To design a more robust artifact, an artifact design based on a design rationale analysis is pivotal. Errors in previous design rationales that led to the degradation of artifact robustness in the past provide valuable knowledge towards improving the robust design. However, methods for exposing and analysing errors in design rationale remain unclear. This paper proposes a structured method for a design rationale analysis based on logical structuring. This method provides a well-constructed means of identifying and analysing errors in design rationale from the perspective of knowledge operation.

DATA DESIGN IDEA IN CONTEMPORARY INTERIOR SPACES

Design ideas are characterized by being able to develop and strive to find the best and most beautiful in terms of functionality and its integration and in terms of compatibility and harmony with what the performance use requires in terms of effectiveness reflected on the user, and here the sources of the idea are identical with what corresponds to the materials and materials being means that achieve comfort and good feeling, with Taking into consideration the technical fields and the wide availability of possibilities to achieve the accomplishments of the idea, regardless of the complexity and simplification required in any of the joints of the creative process in the internal spaces. On this basis, the question came to the research problem, which is: What is the importance of the design idea data and how to obtain innovative and unconventional design solutions in contemporary interior spaces. The current research aims to reveal the data of the design idea in the contemporary interior spaces of cultural centers. The theoretical framework included the meaning of the idea, its concept, and its most important data. We have adopted the descriptive approach in the research, reaching the analysis that includes studying the data of the design idea in the contemporary interior spaces of the international cultural centers of architectural designs, Zaha Hadid. The researcher, Dongdaemun Bla, Cultural Center in South Korea has been approved by the research community, represented by three international cultural centers. The most important conclusions are: 1- Creativity is a mental process, the foundations for the process of realizing gaps and missing elements and creating ideas, through which the interior designer goes through with the aim of producing new ideas in the design of contemporary interior spaces. 2- The design idea went in directions completely different from the traditional aspects based on the level of activation of aesthetic reflections, through its reliance on hybrid design relationships with an exotic and inspirational characteristic that diverges from the previous design system.

Preliminary Design Tool for Centrifugal Compressors

Commonly, compressor designs rely on previous machines that can be slightly modified to achieve new operating requirements. In some cases, however, a completely new design is needed because no previous designs are available for the specific operating range of interest. Without a previous design, it is difficult to make initial trade studies of an appropriate impeller diameter, speed, and number of compression stages. While new compressor designs are a common occurrence in applied research applications, conceptual design typically require a point-by-point process to balance the requirements with acceptable design parameters. This can be done manually or through automation to optimize for a specific operating parameter, such as efficiency. The authors are unaware of any tool available that bounds the range of design parameters for a centrifugal compressor stage without applying a point-by-point method. In this work, two common references for conceptual compressor design were cross-checked to develop an Excel-based tool to quickly determine the design space for a given set of compressor requirements. The tool relies on design experience presented by Aungier and Baljé as well as other experience drawn from available literature [1],[2]. The sheet functions from a series of assumptions based within the design experience and requires inputs regarding the desired power, fluid flow rate, and total-to-total pressure ratio, as well as inlet conditions. While the tool currently assumes an ideal gas, future revisions can include calls to REFPROP for a real gas.

Location-based key management, data authentication and aggregation in wireless sensor networks

The first design presents a novel location-based key management and en-route data authentication proposal. It divides the whole sensing area into a number of location cells. A group of location cells consist of a logical group. A pairwise key between two sensor nodes is established based on grid-based bivariate t-degree polynomials. Any valid reading report needs to collect enough message authentication code (MACs) from different neighbours. These pairwise keys used for generating the MAC are forwarded several hops down to the base station for future en-route data authentication. The second design proposes a greedy location-based secure and energy-efficient data aggregation approach. It further utilizes data aggregation based on the previous design by setting up control groups, applying pattern codes, selecting and switching control head nodes dynamically and periodically. In addition, different from the first design, it only requires control head nodes to collect enough MACs in each reading report. Extensive analysis, evaluations and experiments show us that both designs are secure, efficient and resilient.

Location-based key management, data authentication and aggregation in wireless sensor networks

The first design presents a novel location-based key management and en-route data authentication proposal. It divides the whole sensing area into a number of location cells. A group of location cells consist of a logical group. A pairwise key between two sensor nodes is established based on grid-based bivariate t-degree polynomials. Any valid reading report needs to collect enough message authentication code (MACs) from different neighbours. These pairwise keys used for generating the MAC are forwarded several hops down to the base station for future en-route data authentication. The second design proposes a greedy location-based secure and energy-efficient data aggregation approach. It further utilizes data aggregation based on the previous design by setting up control groups, applying pattern codes, selecting and switching control head nodes dynamically and periodically. In addition, different from the first design, it only requires control head nodes to collect enough MACs in each reading report. Extensive analysis, evaluations and experiments show us that both designs are secure, efficient and resilient.

Cryoegg: development and field trials of a wireless subglacial probe for deep, fast-moving ice

Subglacial hydrological systems require innovative technological solutions to access and observe. Wireless sensor platforms can be used to collect and return data, but their performance in deep and fast-moving ice requires quantification. We report experimental results from Cryoegg: a spherical probe that can be deployed into a borehole or moulin and transit through the subglacial hydrological system. The probe measures temperature, pressure and electrical conductivity in situ and returns all data wirelessly via a radio link. We demonstrate Cryoegg's utility in studying englacial channels and moulins, including in situ salt dilution gauging. Cryoegg uses VHF radio to transmit data to a surface receiving array. We demonstrate transmission through up to 1.3 km of cold ice – a significant improvement on the previous design. The wireless transmission uses Wireless M-Bus on 169 MHz; we present a simple radio link budget model for its performance in cold ice and experimentally confirm its validity. Cryoegg has also been tested successfully in temperate ice. The battery capacity should allow measurements to be made every 2 h for more than a year. Future iterations of the radio system will enable Cryoegg to transmit data through up to 2.5 km of ice.

Design a Low Power and High Speed Parity Checker using Exclusive–or Gates

In the presented paper we designed the parity checker by using EX-OR modules. The two EX-OR modules are presented to design the parity checker and correlated their outcomes based on the constraints like power, area, delay and power delay product (PDP). The previous design is with eight transistors EX-OR, but in the present six transistors EX-OR is used to design the parity checker. While correlating the parity checker design with 8T EX-OR and 6T EX-OR, the 6T EX-OR parity checker design gives optimized power, delay, area and PDP over the 8T EX-OR parity checker design. Simulations are done by using the 130nm mentor graphics tool. Finally the constraints like power, area, delay and PDP gets optimized successfully with the presented technology. Also, alternatively we can replace EXOR modules with NAND modules to design parity checker.

A REVIEW STUDY ON ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING

The advancement in the up-grading of technology and proliferation in data accessibility is changing the economics of digital communication; therefore, this enables the reexamining of the previous design and approach to network architectures. This research paper focused on advancements in technology in the past few years and concentrate on OFDM (Orthogonal Frequency Division Multiplexing).