Rigid-Flexible Coupled Dynamics and PD-Robust Control Design for the Spacecraft with Rotating Solar Panels

The dynamical model for the spacecraft with multiple solar panels and the cooperative controller for such spacecraft are studied in this paper. The spacecraft consists of a rigid platform and two groups of flexible solar panels, where solar panels could be driven to rotate by the connecting shaft. The flexible solar panel involves the use of the orthogonal polynomial in two directions to describe its elastic deformation. By using the Rayleigh–Ritz method, the characteristic equation is derived to obtain natural frequencies and modal shapes of the whole spacecraft. Then the discrete rigid-flexible coupled dynamical equation of the spacecraft is obtained by using the Hamiltonian principle. The equation involves the coupling of the attitude maneuver, solar panels’ driving and vibration suppression. These dynamical behaviors are addressed by the rigid-flexible coupled mode for the first time in this paper. Based on the dynamical equation, the cooperative control scheme is designed by combing the proportional-differential and robust control method. Numerical results show the accuracy of the present modelling method and the validation of the control strategy. The modal analysis implies the complex rigid-flexible coupled characteristic between the central platform and flexible solar panels. The proposed control scheme can maintain the attitude stability while solar panels are being driven, as well as the vibration suppression of flexible solar panels.

Modular Software Architecture for Local Smart Building Servers

This paper presented the architecture and construction of a novel smart building system that could monitor and control buildings’ use in a safe and optimal way. The system operates on a Raspberry local server, which could be connected via the cloud technology to a central platform. The local system includes nine modules that inter-communicate. The system detects sensor faults, and provides a friendly interface to occupants. The paper presented the software architecture IoT used for the building monitoring and the use of this system for the management of fifteen social housing units during a year. The system allowed the investigation of indoor comfort and both energy and hot water consumptions. Data analysis resulted in the detection of abnormal energy consumptions. The system could be easily used in buildings’ management. It works in a plug-and-play mode.

Shameful Technological Impertinence: Consumer Ambivalence among iPad Early-Buyers

This article is motivated by the excessive success of Apple’s iPad, introduced in 2010, questioning the motives for acquiring the product at the time of launch. The purpose is to understand the decision to buy an expensive product that had a fairly undefined use. On the basis of in-depth interviews of ‘early-buyers’ (‘early adopters’) of the iPad, we examine, in this article, justifications for the acquisition of such an ‘open technology’ use. Using theories of consumer society (Veblen, Bauman, Debord), Protestant ethics (Weber), impression management (Goffman, Leary) and group identity (Maffesoli), we develop, in the analysis, the concept of shameful technological impertinence concerning the ambiguity between frugality as value and consumer-based identity related to the latest technology. A reflection on this concept contributes to an understanding of how excessive technology consumption, on the one hand is followed by an unashamed desire to show off new ‘gadgets’ and on the other hand, a more shameful self-presentation defending the purchase. Today, just over ten years after the launch of the iPad and our interviews, the iPad is taken for granted as a central platform for a number of applications, for everything from personal entertainment to work- and school-related use. In light of this, we conclude with a reflection on how shameful technological impertinence as a more generic concept will be relevant in some phases rather than others, as new innovations are brought into use. The project is limited to the first iPad and its users, and further research could investigate a larger array of consumer electronics and how attitudes towards buying could be increasingly influenced by a growing concern about the abuse of natural resources.

Architecting an Enterprise Data Lake, A Covid19 Case Study

Data is increasing at an enormous rate every day. Traditionally data has resided in silosacross any organization,so it’s difficult to have a complete picture for data driven business decision making. Data lake addresses the problem of rate of increase of data by providing “schema on read”, better integration and cheaper storage. It also solves the data silos problemby providing a central platform for a variety of data housing needs. However, implementing a data lake becomes challenging as the implementation needs to address the additional needs like metadata management, data discovery, data governance, data lifecycle management, security and centralized access controls mechanisms. This paper intends to provide a comprehensive architecture of data lake to address these challenges. We have also conducted and documented our experiments with publicly available datasets about COVID19 to validate the design and applicability of the proposed architecture for business analytics purposes.

Nonlinear multi-mode electromagnetic insole energy harvester for human-powered body monitoring sensors: Design, modeling, and characterization

The current research in wearable electronics is trending towards miniaturization, portability, integration, and sustainability, with the harvesting of biomechanical energy seen as a promising route to improve the sustainability of these wearable electronics. Efforts have been made to prolong operational life of these harvesters, to overcome energy dissipation, lowering resonant frequency, attaining multi-resonant states as well as widening frequency bandwidth of these biomechanical energy harvesters. Herein, an electromagnetic insole energy harvester (EMIEH), capable of efficiently harvesting low-frequency biomechanical energy, has been designed, fabricated and experimentally tested. The core component in the device is the vibrating circular spiral spring, holding two magnets as the driving force on the central platform of the circular spiral spring, and just in-line with the upper and lower wound coils. It has been shown that the harvester exhibits higher sensitivity to low-frequency external vibrations than conventional cantilever-based designs, and hence allows low impact energy harvesting such as harvesting energy from walking, running and jogging. The experimentally-tested four resonant frequencies occurred at 8.9 Hz, 28 Hz, 50 Hz, and 51 Hz. At the first resonant frequency of 8.9 Hz under base acceleration of 0.6 g, the lower electromagnetic generator can deliver a peak power of 664.36 µW and an RMS voltage of 170 mV to a matching load resistance of 43.5 Ω. The upper electromagnetic generator can contribute an RMS voltage of 85 mV, corresponding to the peak power of 175 µW across 41 Ω under the same experimental condition. Finally, the harvester has been integrated into the shoe and it is able to charge a 100 µF capacitor up to 1 Volt for about 8 minutes foot movement. The result has remarkable significance in the development of wireless body monitoring sensors applications.

GLOBAL EXPORT CONTROLS OF CYBER SURVEILLANCE TECHNOLOGY AND THE DISRUPTED TRIANGULAR DIALOGUE

The proliferation and abuse of cyber surveillance technology is a global policy problem. The Wassenaar Arrangement is a central platform of international cooperation for regulating dual-use goods and technologies and the so-called ‘cyber’ amendments to Wassenaar have created a multilateral control mechanism for the export of cyber surveillance technology. Following criticism of the repressive use of ICT-powered surveillance tools supplied by private companies in the early 2010s, Wassenaar States revised the Arrangement to regulate certain types of surveillance. This article begins by examining key features of the cyber amendments. Based on the analysis of recent export control law reforms in the three leading State actors in the production, sales and governance of cyber surveillance technology—namely the United States, China, and the European Union—the article identifies the diminishing importance of the Wassenaar Arrangement. It also shows how approaches in the three jurisdictions diverge not only from the terms of equivalent Wassenaar controls, but also from one another. They all aim to become a stronger and more autonomous entity in the regulation of cyber surveillance technology. In the face of escalating confrontation between the G2 concerning emerging technologies, it will be interesting to see how the EU's turn to a more human rights-centred approach to governing the export of cyber surveillance technology will be received by the US and Chinese governments in the long run and how it will interact with export control reforms designed with competing geopolitical, commercial and security agendas.

A Platform and Multi-sided Market for Translational, Software-defined Medical Research in the Operation Room: OP 4.1 (Preprint)

BACKGROUND While digital and data-based technologies are widespread in various industries in the context of Industry 4.0, the use of smart, connected devices in healthcare is still in its beginnings. Innovative solutions for the medical environment suffer from difficult access to medical device data and high barriers for market entry due to proprietary systems. OBJECTIVE In the proof-of-concept project OP 4.1, we show the business viability of connecting and augmenting medical devices and data through software add-ons by giving companies a technical and commercial platform for the development, implementation, distribution, and billing of innovative software solutions. METHODS The creation of a central platform prototype requires the collaboration of several independent market contenders, amongst them medical users, software developers, medical device manufacturers, and platform providers. A dedicated consortium of clinical and scientific partners as well as industry partners was established. RESULTS We demonstrate the successful development of the prototype of a user-centric, open, and extensible platform for the intelligent support of processes starting with the operation room. By connecting heterogeneous data sources and medical devices from different manufacturers and making them accessible for software developers and medical users, the cloud-based platform OP 4.1 enables the augmentation of medical devices and procedures through software-based solutions. The platform also allows for the demand-oriented billing of applications and medical devices, thus permitting software-based solutions to fast-track their economic development and become commercially successful. CONCLUSIONS The technology and business platform OP 4.1 creates a multi-sided market for the successful development, implementation, distribution, and billing of new software solutions in the operation room and in the healthcare sector in general. Consequently, software-based medical innovation can be translated into clinical routine fast, efficiently, and cost-effectively, optimizing the treatment of patients through smartly assisted procedures.

Application Research of Engineering Construction Standardisation in an Oilfield Development Adjusting Project in Bohai Sea

In order to improve the efficiency and economic benefits of oilfield development, the researchers applied the standardisation achievements of Bohai oilfield engineering construction in the preliminary research and basic design of an oilfield development adjusting project in Bohai Sea for the first time. The application research mainly contains the topside, jacket, living quarter and workover rig of the project. In which, the topside and jacket are researched based on the standardisation achievements of Eight-Legged Central Platform Type B, the living quarter applies the standardised 60 persons living quarter and the workover rig adopts the achievements of workover rig HJX180D. Meanwhile, some optimizations and adjustments are carried out according to the actual needs. Through the application research, the basic design of the new platform is basically consistent with the standardised platform, and some settings are optimized and adjusted. Then the comparison and differences of the settings are analyzed between the two platforms, and the improvement measures are proposed for better application of standardisation achievements. Through the full application research of the standardisation achievements of Bohai oilfield engineering construction, the project is conducive to the improvement of the efficiency and quality in management, research design, procurement and platform construction. As a result, it can save the construction period and cost, and improve the overall economic benefits of the oilfield development. Through the application of the standardised drawings and documents of the standardised topside, jacket, living quarter, workover rig and main equipment, the design period is shortened by 3 months comparing with the conventional period. Moreover, the standardised design of the main structural materials and equipment not only can save the procurement time and reduce cost, but also can facilitate the process management of the equipment and materials. Therefore, the economic benefits of the oilfield are effectively improved, which can provide strong support for the smooth production of the oilfield. The experience accumulated in the application research of standardisation achievements in this project can provide some reference value for the promotion and application of similar projects in the future.