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The Quaternion kinematical differential equation (QKDE) plays a key role in navigation, control and guidance systems. Although explicit symplectic geometric algorithms (ESGA) for this problem are available, there is a lack of a unified way for constructing high order symplectic difference schemes with configurable order parameter. We present even order explicit symplectic geometric algorithms to solve the QKDE with diagonal Pad\`{e} approximation and Cayley transform. The maximum absolute error for solving the QKDE is $\mathcal{O}(\tau^{2\ell})$ where $\tau$ is the time step and $\ell$ is the order parameter. The linear time complexity and constant space complexity of computation as well as the simple algorithmic structure show that our algorithms are appropriate for realtime applications in aeronautics, astronautics, robotics, visual-inertial odemetry and so on. The performance of the proposed algorithms are verified and validated by mathematical analysis and numerical simulation.

Remote ATC simulation training is an emerging technology in aviation education during COVID. Professional training institutions can learn from others, whereas the experiences of developing remote ATC simulation teaching/training with the Start-up company ByteProTeq will be beneficial for the rest of the world to understand the differences and similarities of current remote training and to improve their performance in building a safe and efficient remote training environment. In this paper, we will present three improvements to our remote ATC training: 1) infrastructure upgrading of hardware and software from an existing stand-alone system to a remote network that considers costs, cyber security, system compatibility, et cetera; 2) quality of remote ATC simulation training, compared with traditional face-to-face training, including students and instructors feedback; 3) enhancement of the current remote training system beyond COVID-19 regarding reliability, cyber security, and capacity. This foundation paper will support understanding of the current stage of remote ATC simulation training development with the Start-up company ByteProTeq, during and beyond the COVID-19 pandemic, thereby providing an excellent example for the rest of the world., Comment: 11 pages

Yong-Lin Liu,1 Wei-Min Xiao,1 Man-Qiu Liang,2 Zhi-Qiang Wu,1 Ya-Zhi Wang,1 Jian-Feng Qu,1 Yang-Kun Chen11Department of Neurology, Affiliated Dongguan People’s Hospital, Southern Medical University (Dongguan People’s Hospital), Dongguan, Guangdong Province, People’s Republic of China; 2Department of Radiology, Affiliated Dongguan People’s Hospital, Southern Medical University (Dongguan People’s Hospital), Dongguan, Guangdong Province, People’s Republic of ChinaCorrespondence: Yang-Kun ChenDepartment of Neurology, Affiliated Dongguan People’s Hospital, Southern Medical University (Dongguan People’s Hospital), 3 South Wandao Road, Wanjiang District, Dongguan City, Guangdong Province 523059, People’s Republic of ChinaTel +86 7 692 863 6830Fax +86 07 692 222 2353Email cykun78@163.comPurpose: Wernicke’s encephalopathy (WE) is a severe neurological disorder caused by thiamine deficiency. The most common cause of WE is alcoholism. However, there is a significant paucity of information in the existing literature relating to nonalcoholic WE. In this study, we investigated the clinical characteristics and neuroimaging findings of nine patients with nonalcoholic WE.Patients and methods: We retrospectively collated clinical data from nine patients who had been diagnosed with WE in accordance with established criteria including age, gender, risk factors and clinical manifestations. We also collated initial hematological and neuroimaging findings.Results: The mean age of the nine patients was 54.0±17.1 years; four of these patients (44.4%) were male. All nine patients had a history of fasting (range, 5–47 days) prior to WE. Four of the nine patients (44.4%) exhibited the classical triad, and eight (88.9%) showed alterations in mental status. Magnetic resonance imaging (MRI) scans showed that all nine patients had symmetric lesions of the medial thalamus. MRI als

Hua Sun,*,1 Man Liang,*,2 Na Zheng31Department of Endocrinology, The Affiliated Hospital of Beihua University, Jilin City, Jilin 132011, People’s Republic of China; 2Department of Forensic Science, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430030, Hubei, People’s Republic of China; 3Department of Pathology, Health Science Center, Shen Zhen University, Shenzhen, Guangdong 518066, People’s Republic of China*These authors contributed equally to this workWe read with great interest the recently published article by Vasheghani et al.1 In the article, the authors showed that the prevalence of CAN was increased with prolonged duration of DM, but not the glycemic control level.View the original paper by Vasheghani and colleagues.A Response to Letter has been published for this article.&nbsp

La congestion dans les Terminal Manoeuvring Area (TMA) des aéroports en hub est le principal problème dans le transport aérien chinois. Face au trafic extrêmement dense dans les TMAs, nous pouvons envisager d'automatiser une grande partie des opérations de routine, comprenant la planification, le séquencement et la séparation. Nous proposons dans cette thèse un nouveau système automatisé de séquencement des avions et de fusion des flux vers des pistes parallèles, qui sont utilisées dans la plupart des aéroports chinois. Notre méthodologie intègre un réseau de route 3D nommé Multi-Level and Multi-Point Merge System (MLMPMS) basé sur le concept de l'Area Navigation (RNAV) et un algorithme d'optimisation heuristique hybride pour trouver une solution correcte, opérationnellement acceptable. Un algorithme de Simulated Annealing (SA) spécifique et un module de génération de trajectoire collaborent pour rechercher la solution quasi optimale. Notre objectif est de générer en temps réel des trajectoires sans conflit, minimisant la consommation de carburant et permettant des méthodes de contrôle faciles et flexibles. Dans ce but, nous explorons en permanence les solutions possibles avec le moins de retard et assuront l'atterrissage le plus rapide. Nous déterminons quatre variables de décision pour contrôler chaque vol : l'heure et la vitesse d'entrée dans la TMA, le temps de vol sur l'arc de séquencement et le choix de la piste utilisée. La simulation de trajectoire dans les différentes phases de vol est basée sur le modèle de performances BADA. Dans le cas de l'aéroport de Beijing Capital International Airport (BCIA), les résultats numériques montrent que notre système d'optimisation de bonnes performances sur le séquencement et la fusion des trajectoires. Tout d'abord, il permet d'assurer des performances de résolution conflit très stables pour gérer les flux de trafic continuellement denses. Par rapport à l'algorithme Hill Climbing (HC), le SA peut toujours trouver une sol, Congestion in Terminal Manoeuvring Area (TMA) at hub airports is the main problem in Chinese air transportation system. Facing extremely dense operations in complex TMA, we can consider reducing traffic complexity by solving all potential conflicts in advance with a feasible trajectory control for controllers, or automating a large proportion of routine operations, such as sequencing, merging and spacing. As parallel runways are a common structure of Chinese hub airports, in this thesis, we propose a novel system to integrated sequencing and merging aircraft to parallel runways. Our methodology integrates a Area Navigation (RNAV)-based 3D Multi-Level and Multi-Point Merge System (MLMPMS), a hybrid heuristic optimization algorithm and a simulation module to find good, systematic, operationally-acceptable solutions. First, a Receding Horizon Control (RHC) technique is applied to divide 24-hour traffic optimization problem into several sub- problems. Then, in each sub-problem, a tailored Simulated Annealing (SA) algorithm and a trajectory generation module worn together to find a near-optimal solution. Our primary objective is to rapidly generate conflict-free and economical trajectories with easy, flexible and feasible control methods. Based on an initial solution, we continuously explore possible good solutions with less delay and shorter landing interval on runway. Taking Beijing Capital International Airport (BCIA) as a case to study, numerical results show that our optimization system performs well. First, it has very stable de-conflict performance to handle continuously dense traffic flows. Compared with Hill Climbing (HC), the tailored SA algorithm can always guarantee a conflict-free solution not only for the mixed or segregated parallel approach (arrivals only) pattern, but also for the independent parallel operation (integrated departures and arrivals) pattern. Second, with its unique Multi-Level Point Merge (ML-PM) route network, it can provide a good trajec