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107. Smart-clothing Platform for Elderly Care: Monitoring of Physical Activities, Physiological Status and Outdoor Localization in Real Time

Author

Niu, He

Subjects
clothing, klær, eldreomsorg, mikroteknologi, nanoteknologi, eldercare, Teknologi: 500 [VDP]
Abstract

The emerging research on smart clothing platform in health monitoring field has been a great concern both in academia and products industry. And with the problem of global population aging, the need for more services with higher quality in eldercare environment is poised to become significant. Advances in micro technologies, flexible sensors and related technologies make a new smart clothing can be developed to enhance the efficiency of eldercare, illness and unpredictable event prevention with monitoring and alarming method. This master thesis provides a design of a smart-clothing platform based on embedded and wearable technology, which is a continuous monitoring to track the physical activities, physiological status and achieves automatic outdoor positioning for the elderly. Based on sensor network technology and Qt Creator development environment, the platform uses a greater number of sensor nodes to detect the different parts of the body to improve the detection accuracy. Front-end system uses STC12C5A60S2 microcontroller as the central node to receive the data of each sub-node, and through the wireless network data transfer to the PC for analysis. PC research algorithm to deal with the relevant data. Finally, the human-computer interface display and store results. Compared with traditional smart clothing, this system can provide a multifunctional specialization monitoring for elderly who need extra cares. This thesis is organized as follows. Chapter 1is an introduction including the smart clothing concept, the review of previous works, motivations, and the objectives of this thesis is also given in this chapter. Chapter 2 introduces system functions and the whole design scheme which covers both the hardware and software design. In chapter 3, the advanced relevant algorithms used for posture recognition is presented in order to provide the necessary knowledge, and the final algorithm used in this thesis is explained in this chapter. The chapter 4 and 5 respectively introduce the system hardware implementation and the software implementation. The system consists of wearable nodes (6 subnodes and 1 central node) and PC human-computer interaction interface, which are explained in detail in both chapters. Chapter 6 shows the experimental results of this smart-clothing platform and analyzes them in turn. On the basis of Chapter 6, Chapter 7 concludes the advantages and disadvantages of this system and gives the recommendations for future works. Additionally, the software source code of host computer and the lower computer are given in the appendix

Published
2017

111. Potential of secondary aerosol formation from Chinese gasoline engine exhaust

Author

Du, Zhuofei, primary, Hu, Min, additional, Peng, Jianfei, additional, Guo, Song, additional, Zheng, Rong, additional, Zheng, Jing, additional, Shang, Dongjie, additional, Qin, Yanhong, additional, Niu, He, additional, Li, Mengren, additional, Yang, Yudong, additional, Lu, Sihua, additional, Wu, Yusheng, additional, Shao, Min, additional, and Shuai, Shijin, additional

Published
2018
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137. Colloidal Synthesis and Thermoelectric Properties of CuFeSe2 Nanocrystals.

Author

Zhang, Bing-Qian, Liu, Yu, Zuo, Yong, Chen, Jing-Shuai, Song, Ji-Ming, Niu, He-Lin, and Mao, Chang-Jie

Subjects
NANOCRYSTALS, THERMOELECTRICITY, CHALCOGENIDES
Abstract

Copper-based chalcogenides that contain abundant, low-cost and environmentally-friendly elements, are excellent materials for numerous energy conversion applications, such as photocatalysis, photovoltaics, photoelectricity and thermoelectrics (TE). Here, we present a high-yield and upscalable colloidal synthesis route for the production of monodisperse ternary I-III-VI2 chalcogenides nanocrystals (NCs), particularly stannite CuFeSe2, with uniform shape and narrow size distributions by using selenium powder as the anion precursor and CuCl2•2H2O and FeCl3 as the cationic precursors. The composition, the state of valence, size and morphology of the CuFeSe2 materials were examined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscope (TEM) and high resolution transmission electron microscope (HRTEM), respectively. Furthermore, the TE properties characterization of these dense nanomaterials compacted from monodisperse CuFeSe2 NCs by hot press at 623 K were preliminarily studied after ligand removal by means of hydrazine and hexane solution. The TE performances of the sintered CuFeSe2 pellets were characterized in the temperature range from room temperature to 653 K. Finally, the dimensionless TE figure of merit (ZT) of this Earth-abundant and intrinsic p-type CuFeSe2 NCs is significantly increased to 0.22 at 653 K in this work, which is demonstrated to show a promising TE materialand makes it a possible p-type candidate for medium-temperature TE applications. [ABSTRACT FROM AUTHOR]

Published
2018
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148. Evaluating Different Implementations of Online Junction Temperature Sensing for Switching Power Semiconductors.

Author

Niu, He and Lorenz, Robert D.

Subjects
POWER semiconductors, SWITCHING power supplies, ELECTRIC switchgear
Abstract

Switching power semiconductor online junction temperature Tj sensing is essential for device switching performance evaluation, device switching control, and device lifetime optimization. The contribution of this paper is a detailed evaluation of the implementation issues (including circuit invasiveness, hardware integration, signal processing, and so forth) of different online Tj sensing methods. This paper includes Tj sensing methods based on device power dissipation, Tj sensing methods based on the “sensor-on-die technology,” Tj sensing methods based on device on-state analysis, and Tj sensing methods based on device switching transients. Advantages and limits of these methods are also provided. [ABSTRACT FROM AUTHOR]

Published
2017
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