Aerodynamic model identification of an autonomous aircraft for airborne wind energy

Airborne wind energy (AWE) refers to a novel technology capable of harvesting energy from wind by flying crosswind patterns with tethered autonomous aircraft. Successful design of flight controllers for AWE systems relies on the availability of accurate mathematical models. Due to an expected nonconventional structure of the airborne component, the system identification procedure must be ultimately addressed via an intensive flight test campaign to gain additional insight about the aerodynamic properties. In this paper, the longitudinal dynamics of a rigid‐wing, high lift, autonomous aircraft for AWE are identified from experimental data obtained within flight tests. The aerodynamic characteristics are estimated via an efficient time‐domain multiple experiments model‐based parameter estimation algorithm.     

In-Room Ultraviolet Air Filtration Units Reduce Airborne Particles During Total Joint Arthroplasty

Reducing airborne bioburden in total joint arthroplasty (TJA) is of critical importance. The efficacy of crystalline ultraviolet-C (C-UVC) filtration in reducing bioburden in a dynamic operating room (OR) environment has not been evaluated. We assessed whether C-UVC filtration reduced (i) total particle counts (TPC); (ii) viable particle counts (VPC); and (iii) colony-forming units (CFUs). Fifty primary TJA cases were performed in a positive-pressure OR; 25 cases with the C-UVC unit and 25 cases without. The air was sampled by a particle counter and an impact air sampler to measure particle counts and CFUs, respectively. To compare TPC, VPC, and CFU/m³ between groups, independent t tests and multivariate regression, adjusted for number of OR staff and door openings, were performed. The C-UVC group had significantly lower TPC (2.6 × 10⁶ vs. 4.7 × 10⁶ particles, p = 0.001) and VPC (18,605 vs. 27,516 particles, p = 0.001). There were fewer CFUs in the C-UVC group (10.9 CFU/m³ vs. 13.7 CFU/m³, p = 0.163). Multivariate analysis identified C-UVC filtration as a significant predictor of decreased TPC (β = −0.44, p = 0.002) and VPC (β = −0.47, p = 0.001) after accounting for door openings and number of OR staff. The reduction in CFUs was not significant on multivariate analysis. In this prospective pilot study, a C-UVC air disinfection and recirculation unit led to a significant reduction in both TPC and VPC and a non-significant reduction in CFU. Statement of clinical significance: Further studies are needed to investigate the effects of C-UVC filtration units on surgical-site infection rates. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:431-437, 2020     

非接触式医疗监测雷达研究进展

介绍了非接触式医疗监测雷达相比于传统的呼吸和心电监护仪的优势,从3种不同雷达体制的角度总结回顾了近10 a来医用生命监测雷达系统的研究现状,概括比较了呼吸和心跳信号的提取、分离、杂波抑制等算法,并指出了各种算法的优缺点,最后对非接触式生命监测雷达的发展趋势进行了探讨和展望.     

建立气传花粉日播报平台对过敏性鼻炎防治的意义及相关因素分析

目的：收集呼和浩特气传花粉数据,分析其分布特征及气候影响因素,建立花粉浓度日播报平台,指导患者有效防护,为临床提供辅助诊疗引导。方法：花粉采集仪收集花粉,显微镜下进行阅片计数,记录同期气象因素,通过以微信公众平台为主的多种播报途径进行花粉日播报。结果：共收集花粉26825粒,鉴别种属18类,花粉播散存在春季和夏秋季两个高峰段,其分布规律与每日温差正相关,平台用户流量与花粉浓度趋势走形呈一致性变化,夏秋季用户流量峰值较春季高。结论：呼和浩特气传花粉存在两个高峰段,花粉浓度同每日温差存在正相关,花粉浓度日播报可为临床提供辅助诊疗引导。     

四川省成都市城区气传花粉监测

目的探索四川省成都市城区气传花粉的种类、数量及飘散规律。方法应用重力沉降法于2018年3月1日至2019年2月28日在四川省成都市城区进行为期1年的连续每日气传花粉曝片。结果共收集到花粉139520粒/1000 mm 2,能鉴定的花粉总计隶属36科、31属、2个种。其中构属花粉含量最高,达81754粒/1000 mm 2,占全年花粉总量的58.60%,其播粉期为3~4月,高峰期为3月下半月至4月上半月;其次是柏科花粉,达27518粒/1000 mm 2,占全年花粉总量的19.72%,其播粉期为1~3月,高峰期为1月下旬至3月上旬;大麻/葎草属占第三位,花粉含量5112粒/1000 mm 2,占全年花粉总量的3.66%,其播粉期为8~10月,高峰期为8月下旬至10月下旬。上述3种花粉为本地区优势气传花粉,合计占全年花粉总量的81.98%。含量超过1%的花粉还依次包括银杏、桦木属、松属、悬铃木属、枫杨属及蒿属花粉。全年花粉含量月分布呈现2个高峰,第一高峰为1~5月,主要气传花粉为构属、柏科、银杏、桦木属、松属、悬铃木属、枫杨属等树木花粉,占全年花粉总量的89.38%。第二高峰为8~10月,主要气传花粉为大麻/葎草属、蒿属等莠草花粉,占全年花粉总量的5.04%。结论本地区花粉季节有两个:春季为主要花粉季节,主要气传花粉为构属、柏科等树木花粉;夏秋季为次要花粉季节,主要花粉气传为大麻/葎草属、蒿属等莠草花粉。构属、柏科、大麻/葎草属花粉为本地区优势气传花粉,构属花粉为本地区绝对优势气传花粉。