Adaptive 3D ray tracing approach for indoor radio signal prediction at 3.5 GHz

This paper explained an adaptive ray tracing technique in modelling indoor radio wave propagation. As compared with conventional ray tracing approach, the presented ray tracing approach offers an optimized method to trace the travelling radio signal by introducing flexibility and adaptive features in ray launching algorithm in modelling the radio wave for indoor scenarios. The simulation result was compared with measurements data for verification. By analyzing the results, the proposed adaptive technique showed a better improvement in simulation time, power level and coverage in modelling the radio wave propagation for indoor scenario and may benefit in the development of signal propagation simulators for future technologies.

The TL;DR Charter: Speculatively Demystifying Privacy Policy Documents and Terms Agreements

Privacy policy and term agreement documents are considered the gateway for software adoption and use. The documents provide a means for the provider to outline expectations of the software use, and also provide an often-separate document outlining how user data is collected, stored, and used--including if it is shared with other parties. A user agreeing with the terms, assumes that they have a full understanding the terms of the agreement and have provided consent. Often however, users do not read the documents because they are long and full of legalistic and inconsistent language, are regularly amended, and may not disclose all the details on what is done to the user data. Enforcing compliance and ensuring user consent have been persistent challenges to policy makers and privacy researchers. This design fiction puts forward an alternate reality and presents a policy-based approach to fording the consent gap with the TL;DR Charter: an agreement governing the parties involved by harnessing the power of formal governments, industry, and other stakeholders, and taking users expectation of privacy into account. The Charter allows us as researchers to examine the implications on trust, decision-making, consent, accountability and the impact of future technologies.

Overview of Propulsion Systems for Unmanned Aerial Vehicles

Unmanned Aerial Vehicle (UAV) propulsion technology is significantly related to the flight performance of UAVs, which has become one of the most important development directions of aviation. It should be noted that UAVs have three types of propulsion systems, namely the fuel, hybrid fuel-electric, and pure electric, respectively. This paper presents and discusses the classification, working principles, characteristics, and critical technologies of these three types of propulsion systems. It is helpful to establish the development framework of the UAV propulsion system and provide the essential information on electric propulsion UAVs. Additionally, future technologies and development, including the high-power density motors, converters, power supplies, are discussed for the electric propulsion UAVs. In the near future, the electric propulsion system would be widely used in UAVs. The high-power density system would become the development trend of electric UAVs. Thus, this review article provides comprehensive views and multiple comparisons of propulsion systems for UAVs.

Highly Reliable Flexible Device With Charge Compensation Layer

Flexible devices fabricated with polyimide (PI) substrate are crucial for foldable, rollable, or stretchable products in various applications. However, inherent technical challenges remain in mobile charge induced device instabilities and image retention, significantly hindering future technologies. We introduced a new barrier material, SiCOH, into the backplane of amorphous indium-gallium-zinc-oxide (a–IGZO) thin-film transistors (TFTs) that were then implemented into production-level flexible panels. We found that the SiCOH layer effectively compensates the surface charging induced by fluorine ions at the interface between the PI substrate and the barrier layer under bias stress, thereby preventing abnormal positive Vth shifts and image disturbance. The a–IGZO TFTs, metal-insulator-metal (MIM), and metal-insulator-semiconductor (MIS) capacitors with the SiCOH layer demonstrate reliable device performance, Vth shifts, and capacitance changes with an increase in the gate bias stress. A flexible device with SiCOH enables the suppression of abnormal Vth shifts associated with PI and plays a vital role in the degree of image sticking phenomenon. This work provides new inspirations to creating much improved process integrity and paves the way for expediting versatile form-factors.

Economics of an Additive Manufactured Heat Exchanger for Concentrating Solar Power

Developing low cost, high efficiency heat exchangers (HX) for application in concentrated solar power (CSP) is critical to reducing CSP costs. However, the extreme operating conditions in CSP systems present a challenge for typical high efficiency HX manufacturing processes. We describe a process-based cost model (PBCM) to estimate the cost of fabricating an HX for this application using additive manufacturing (AM). The PBCM is designed to assess the effectiveness of different designs, processes choices, and manufacturing innovations to reduce HX cost. We describe HX design and AM process modifications that reduce HX cost from a baseline of$780/kW-thto$570/kW-th. We further evaluate the impact of alternative current and potential future technologies on HX cost, and identify a pathway to further reduce HX cost to$270/kW-th.

Performance of reservoir computing in a random network of single-walled carbon nanotubes complexed with polyoxometalate

Molecular neuromorphic devices are composed of a random and extremely dense network of single-walled carbon nanotubes (SWNTs) complexed with polyoxometalate (POM). Such devices are expected to have the rudimentary ability of reservoir computing (RC), which utilizes signal response dynamics and a certain degree of network complexity. In this study, we performed RC using multiple signals collected from a SWNT/POM random network. The signals showed a nonlinear response with wide diversity originating from the network complexity. The performance of RC was evaluated for various tasks such as waveform reconstruction, a nonlinear autoregressive model, and memory capacity. The obtained results indicated its high capability as a nonlinear dynamical system, capable of information processing incorporated into edge computing in future technologies.

Unpredictable Verticality: Paradigm of a Vertical City

<p>With the densification of urban cities, our urban concrete jungles are populated by self-supporting and monolithic building blocks such as high rises and skyscrapers, connected only by the ground plan that they sit on. Although the buildings of today’s cities are getting taller, the architecture of today’s cities is still being developed on a two-dimensional template, where ground is the base plane and tall buildings remain independent to one another. This has created a segregation between the claimed internal spaces of our built environment and the public domain of architecture within the vertical realm of our urban fabric. This thesis speculates what vertical architecture of the future could be like if we challenge the conventional perception of our claimed vertical space, proposing an alternative while exploring the idea of a three-dimensional urban fabric. The research also encapsulates exploration of future technologies that may aid in the feasibility of this type of vertical architecture. Utilizing a design-led research approach, design experiments were employed to explore different ideologies surrounding futuristic alternatives in approaching vertical architecture. The research explores the proposition through design experiments of three different scales, namely, an installation exploring connectivity through abstraction, a ‘mid-scale’ vertical residence and a vertical city at a public scale. This research was predominantly influenced by the theoretical works of Yona Friedman, Nat Chard, Lebbeus Woods and Cedric Price. Their works were analyzed and merged to generate a hybrid concept for an alternate utilization of vertical space.</p>

Unpredictable Verticality: Paradigm of a Vertical City

<p>With the densification of urban cities, our urban concrete jungles are populated by self-supporting and monolithic building blocks such as high rises and skyscrapers, connected only by the ground plan that they sit on. Although the buildings of today’s cities are getting taller, the architecture of today’s cities is still being developed on a two-dimensional template, where ground is the base plane and tall buildings remain independent to one another. This has created a segregation between the claimed internal spaces of our built environment and the public domain of architecture within the vertical realm of our urban fabric. This thesis speculates what vertical architecture of the future could be like if we challenge the conventional perception of our claimed vertical space, proposing an alternative while exploring the idea of a three-dimensional urban fabric. The research also encapsulates exploration of future technologies that may aid in the feasibility of this type of vertical architecture. Utilizing a design-led research approach, design experiments were employed to explore different ideologies surrounding futuristic alternatives in approaching vertical architecture. The research explores the proposition through design experiments of three different scales, namely, an installation exploring connectivity through abstraction, a ‘mid-scale’ vertical residence and a vertical city at a public scale. This research was predominantly influenced by the theoretical works of Yona Friedman, Nat Chard, Lebbeus Woods and Cedric Price. Their works were analyzed and merged to generate a hybrid concept for an alternate utilization of vertical space.</p>