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Reconfigurable intelligent surface (RIS) and spatial scattering modulation (SSM) are promising candidates for future generations of wireless communication. The former provides an enhanced transmission environment by providing an alternative communication path, while the latter boosts spectral efficiency. In this letter, we firstly propose a novel uplink millimeter-wave (mmWave) communication system that utilizes both RIS and SSM to support data transmission over wireless channels. Specifically, we design the reflecting phase shifters at the RIS to support the two-hop communications. Moreover, a maximum likelihood detector is adopted to a new system with RIS-SSM and a new analytical expression for a tight union upper bound on the bit error rate (BER) is derived. Monte Carlo simulation results are provided to verify the accuracy of the derived analytical expression. Numerical results reveal that the proposed RIS-SSM scheme has a significantly lower BER than the traditional SSM.

Glomerular filtration rate (GFR) estimation equations using creatinine and Cystatin-C appear to be superior to those based on creatinine or Cystatin-C in older adults. We sought to compare the performances of those based on creatinine and Cystatin-C in Chinese older adults with chronic kidney disease (CKD). A total of 368 Chinese elderly with CKD underwent the dynamic imaging with technetium-99m diethylene-triamine-pentaacetic acid (99mTc-DTPA), and serum creatinine and Cystatin-C were measured on the same day. The comparison of GFR equations which were creatinine and Cystatin-C-based including chronic kidney disease epidemiology collaboration (CKD-EPI) equation (CKD-EPI-Cr-Cys), Berlin Initiative Study (BIS) equation (BIS-Cr-Cys, also known as BIS-2), MA equation (MA-Cr-Cys), and FENG equation (FENG-Cr-Cys) was conducted. Four equations overestimated GFR except for BIS-2 equation in mGFR ≥ 60 ml/min/1.73 m2 (bias: − 1.40, p = 0.7) and CKD-EPI-Cr-Cys equation in mGFR

Measurement and variation control of geometrical Key Characteristics (KCs), such as flatness and gap of joint faces, coaxiality of cabin sections, is the crucial issue in large components assembly from the aerospace industry. Aiming to control geometrical KCs and to attain the best fit of posture, an optimization algorithm based on KCs for large components assembly is proposed. This approach regards the posture best fit, which is a key activity in Measurement Aided Assembly (MAA), as a two-phase optimal problem. In the first phase, the global measurement coordinate system of digital model and shop floor is unified with minimum error based on singular value decomposition, and the current posture of components being assembly is optimally solved in terms of minimum variation of all reference points. In the second phase, the best posture of the movable component is optimally determined by minimizing multiple KCs' variation with the constraints that every KC respectively conforms to its product specification. The optimal models and the process procedures for these two-phase optimal problems based on Particle Swarm Optimization (PSO) are proposed. In each model, every posture to be calculated is modeled as a 6 dimensional particle (three movement and three rotation parameters). Finally, an example that two cabin sections of satellite mainframe structure are being assembled is selected to verify the effectiveness of the proposed approach, models and algorithms. The experiment result shows the approach is promising and will provide a foundation for further study and application. © 2013 The Authors.

Materials of satellite integration truss frame are required to withstand temperature that range from about – 250 °C ~ + 150 °C. In order to reduce structural components deformation caused by such temperature change, material of truss frame mostly adopts laminated composite material tubes, whose linear thermal expansion coefficient (LTEC) is very small. Therefore, accurate measurement of LTEC of truss frame materials over a broad temperature range is essential for successful mission. To address this issue, this paper proposes a general experiment platform for measuring LTEC of laminated composite material specimen reaching length up to one meter in the temperature range from – 100 °C to +100 °C. The platform uses light-density optical fiber probe to measure length variation and thermocouple to record temperature variation. Thereafter, the thermal expansion coefficient and its measurement uncertainty can be obtained by establishing and solving mathematical model. Finally, LTEC measurement of a tubular composite materials specimen is conducted. The experiment result demonstrates the validity and practicality of the experiment platform and the measurement accuracy of LTEC which can reach up to 10-7/°C.DOI: http://dx.doi.org/10.5755/j01.ms.21.4.9708