Obstructed View Research Articles

A tree-based automated machine learning approach of the obstructed view factor of thermal radiation in nuclear pebble beds

For the nuclear pebble bed of the high temperature gas-cooled reactor (HTGR), a tree-based automated machine learning approach is developed to discuss the complicated thermal radiation behaviors. The AutoML model for calculating the obstructed view factor between any two particles in the pebble bed includes the gradient boosting regression tree model with the fine-tuned hyperparameters and the analytical base model. Using the discrete packing of the HTR-PM nuclear reactor and the leaped Halton sequence, a large dataset of the view factor under different conditions is generated to train the AutoML model. On the same platform, numerical results show that AutoML model is approximately 5 × 105 times faster than the traditional approach. The Pareto front of the AutoML model indicates that the mean squared error decreases with the model complexity until it reaches the optimal solution. Then, the trained AutoML model is applied to the engineering pebble bed. It is shown that the average radiation exchange factor near the wall is lower than that in the bulk region. In addition, the packing height is also an important parameter for evaluating the radiative behaviors. In particular, when the height of the nuclear pebble bed is less than 20 times particle diameter, it is necessary to consider the contribution of the packing height to the radiation effective thermal conductivity.

Motion Sickness Susceptibility Among Malaysians When Travelling in a Moving Vehicle

Motion sickness is a common problem when travelling in a moving vehicle, especially on land transportation. This occurrence would signify when users are exposed to unexpected movement in an obstructed view. Each user can experience a different level of motion sickness, depending on their susceptibility. This paper aims to study the motion sickness susceptibility among Malaysians using Motion Sickness Susceptibility Questionnaires (MSSQ-Short). A total of 252 Malaysians (146 males and 106 females) completed a set of questionnaires. The questionnaire was distributed through electronic means such as Facebook, WhatsApp, Twitter, and email and consisted of demographic, MSSQ-Short, travel experience as a driver and passenger, and seating position. This study provides a correlation between experiencing motion sickness between childhood and adulthood (r = 0.124, p < 0.05) for the Malaysian sample. This study concludes that Malaysian susceptibility is higher compared to other countries.

GNSS-5G Hybrid Positioning Based on Joint Estimation of Multiple Signals in a Highly Dependable Spatio-Temporal Network

The Global Navigation Satellite System (GNSS) has been widely used in every area of our daily life to provide accurate Positioning, Navigation, and Timing (PNT) services. However, due to the multipatch effect and an obstructed view of the satellite, GNSS receivers are susceptible to large-ranging errors, which are particularly prevalent in urban areas where precise positioning is indispensable. The deployment of the high-spatial-density Fifth-Generation (5G) network makes it possible to provide a broad area with high-precision positioning service. Obviously, it promoting the deep integration of the GNSS system and the 5G mobile communication network and establishing a Highly Dependable Spatio-temporal Network (HDSN) have become an inevitable trend. The existing algorithm for the fusion of multiple signals has difficulty settling problems such as the fast fluctuation of available signal sources and the poor stability of multi-scale multi-type signal estimation in GNSS-5G hybrid networks. Here, we propose a Square Root Unscented Stable Filter (SRUSF) for GNSS and 5G joint positioning with a compact coupled filter group architecture in a highly dependable spatio-temporal network. A stabilized coefficient is added to guarantee positive covariance of the estimation error. The possibility of divergence of filtering results due to the variation in signal sources and the incomplete agreement between the system model and the actual situation are reduced. The simulation results show that the proposed SRUSF method substantially enhances the positioning accuracy and reliability compared with the other five joint estimation methods for multiple signals. This work will enable the terminal of mass users to provide timing and positioning services with unprecedented accuracy and dependability under the GNSS and 5 G-based spatio-temporal network’s architecture.

Endoscopic third ventriculostomy for hydrocephalus after craniovertebral decompression for Chiari malformation type I: technical nuances and surgical pitfalls.

Hydrocephalus after craniovertebral decompression (CVD) for Chiari I malformation (CM-1) is a well-recognised complication. The mainstay of management involves medical management with high-dose steroids and/or acetazolamide, repeated lumbar punctures, external ventricular drainage (EVD) or insertion of a ventriculoperitoneal shunt (VPS). Endoscopic third ventriculostomy (ETV) has only been used a handful of times to treat this type of hydrocephalus with controversial outcomes. Not much is known about this or the technical nuances of this procedure. We report our experience. All children who underwent ETV to treat hydrocephalus post CVD done for CM-1 were identified from a prospectively kept database. Three children were identified (13F, 11F, 13F). The average time to presentation of hydrocephalus was 8days after craniovertebral decompression. Two were successfully treated with ETV with brain imaging showing a reduction in the size of the ventricles post-operatively and not requiring any further cerebrospinal fluid drainage. In one patient, the procedure had to be abandoned after the peel away catheter was introduced into the right ventricle because CSF egressed under high pressure with ventricle walls collapse resulting in an obstructed view. This child ultimately required a VPS. ETV can be used to successfully treat post CVD hydrocephalus in CM-1 patients depending on the aetiology of the hydrocephalus. There are technical and anatomical commonalities between these cases which make it more challenging than an ETV performed in "typical" obstructive hydrocephalus. We describe our experience and review the cases previously reported in the literature.

A hybrid optical-wireless network for decimetre-level terrestrial positioning.

Global navigation satellite systems (GNSS) are widely used for navigation and time distribution1-3, features that are indispensable for critical infrastructure such as mobile communication networks, as well as emerging technologies such as automated driving and sustainable energy grids3,4. Although GNSS can provide centimetre-level precision, GNSS receivers are prone to many-metre errors owing to multipath propagation and an obstructed view of the sky, which occur particularly in urban areas where accurate positioning is most needed1,5,6. Moreover, the vulnerabilities of GNSS, combined with the lack of a back-up system, pose a severe risk to GNSS-dependent technologies7. Here we demonstrate a terrestrial positioning system that is independent of GNSS and offers superior performance through a constellation of radio transmitters, connected and time-synchronized at the subnanosecond level through a fibre-optic Ethernet network8. Using optical and wireless transmission schemes similar to those encountered in mobile communication networks, and exploiting spectrally efficient virtual wideband signals, the detrimental effects of multipath propagation are mitigated9, thus enabling robust decimetre-level positioning and subnanosecond timing in a multipath-prone outdoor environment. This work provides a glimpse of a future in which telecommunication networks provide not only connectivity but also GNSS-independent timing and positioning services with unprecedented accuracy and reliability.

The Impact of Data Augmentation on Tactile-Based Object Classification Using Deep Learning Approach

A safe and versatile interaction between humans and objects is based on tactile and visual information. In literature, visual sensing is widely explored compared to tactile sensing, despite showing significant limitations in environments with an obstructed view. Tactile perception does not depend on those factors. In this paper, a Machine Learning-based tactile object classification approach is presented. The hardware setup is composed of a 3-finger-gripper of a robotic manipulator mounted on the Doro robot of the Robot-Era project. This paper’s main contribution is the augmentation of the custom 20 class 2000 sample tactile time-series dataset using random jitter noise, scaling, magnitude, time warping, and cropping. The effect on the object recognition performance of the dataset expansion is investigated for the neural network architectures MLP, LSTM, CNN, CNNLSTM, ConvLSTM, and deep CNN (D-CNN). The data augmentation methods brought a statistically significant object classification accuracy increase compared to models trained on the original dataset. The best tactile object classification success rate of 72.58% is achieved for the D-CNN trained on an augmented dataset derived from scaling and time warping augmentation.

Sleep Endoscopy and Cine Magnetic Resonance Imaging Evaluation of Children With Persistent Obstructive Sleep Apnea.

To compare findings of same-day cine magnetic resonance imaging (MRI) and drug-induced sleep endoscopy (DISE) and examine how each technique uniquely contributes to the evaluation of persistent obstructive sleep apnea following adenotonsillectomy. Retrospective cohort study. Quaternary care center. Chart review was performed for consecutive patients who underwent same-day cine MRI and DISE between 2015 and 2020. Descriptive statistics are reported, and Cohen kappa coefficients were calculated to evaluate the agreement between cine MRI and DISE for obstruction at the adenoids, lingual tonsils, and tongue base. There were 137 patients, the mean age was 10.4 years (95% CI, 3.2-16.7), and 62.8% were male. The most common sites of obstruction on DISE were the tongue base (86.9%), velum (78.7%), epiglottis (74.5%), inferior turbinate (68.6%), and lingual tonsil (61.3%). The most common sites of obstruction on cine MRI were the hypopharynx (56.3%), tongue base (44.8%), lingual tonsil (38.0%), and macroglossia (37.6%). There was moderate agreement for adenoid hypertrophy (κ = 0.53) and poor agreement for lingual tonsil hypertrophy (κ = 0.15) and tongue base obstruction (κ = 0.09). DISE identified more instances of multilevel obstruction when compared with cine MRI (94.9% vs 48.2%). DISE offered a better examination of nasal and supraglottic obstruction and is sensitive to partial vs complete collapse, while cine MRI offered better soft tissue resolution for lymphoid tissue hypertrophy and provided a global view of primary and secondary airway obstruction. Cine MRI and DISE are complementary modalities in the evaluation of children with persistent obstructive sleep apnea.

A data-driven deep learning model of radiative heat transfer in dense granular systems

Radiative heat transfer has attracted increasing research interest in various dense granular systems, including large-scale nuclear pebble-bed reactors, fusion breeder blankets, packed beds, metal powder beds and granular lunar regolith simulants. The optimised ray tracing method (ORTM) with a Sobol quasi-random sequence is proposed to calculate the obstructed view factor between spheres, and it converges much faster than that with the traditional pseudorandom number sampling method. Based on discrete particle packing of nuclear pebble bed HTR-PM and random particle generation, a large obstructed view factor dataset of thermal radiation is generated by parallel CUDA computing for training a deep learning regression model to discuss the packing-property linkage for radiative heat transfer in the large-scale particle bed. Compared with other approaches, the deep residual neural network (ResNet) with the swish activation function applied in this paper is found to be the best neural network architecture for view factor prediction without vanishing gradients or model degradation problems during training. The testing error of the trained deep learning model is <1.0 × 10-4 for over 99.96% view-factor cases in nuclear pebble beds, and it has proven to be 7.3 × 105 times faster than the traditional numerical method in view-factor calculations. This makes it feasible to explore the local and macroscopic thermal radiation behaviours in large-scale pebble beds filled with up to 1.0 × 107 spheres.

An Augmented Warning System for Pedestrians: User Interface Design and Algorithm Development

Warning pedestrians of oncoming vehicles is critical to improving pedestrian safety. Due to the limitations of a pedestrian’s carrying capacity, it is crucial to find an effective solution to provide warnings to pedestrians in real-time. Limited numbers of studies focused on warning pedestrians of oncoming vehicles. Few studies focused on developing visual warning systems for pedestrians through wearable devices. In this study, various real-time projection algorithms were developed to provide accurate warning information in a timely way. A pilot study was completed to test the algorithm and the user interface design. The projection algorithms can update the warning information and correctly fit it into an easy-to-understand interface. By using this system, timely warning information can be sent to those pedestrians who have lower situational awareness or obstructed view to protect them from potential collisions. It can work well when the sightline is blocked by obstructions.

Persistent Hymen in a Jersey Crossbred Heifer-A Novel Approach with Borescope

Background: Visualizing the internal genital organs in cattle using vaginoscope or endoscope is a costly affair and practically it is not possible to use this instrument in diagnosis of anatomical defects causing infertility under field conditions. An attempt was made to replace the costly instruments with low cost and easily available borescope in the diagnosis of persistent hymen in a Jersey crossbred heifer and the procedure has been reported for the benefit of field veterinarians and theriogenologists.Methods: A Jersey crossbred heifer with normal estrous cycle length and that failed to conceive even after 6 inseminations with fertile semen was presented to the Gynaecological ward. Rectal examination revealed a fluctuating swelling in the vagina. Vaginal examination revealed obstruction in the passage and the vaginal speculum could not be progressed into the vagina. Ultrasonographic examination revealed hypoechoic fluid in the vaginal cavity. A novel approach with borescope revealed a clear view of the membranous obstruction at the level of vagino-vestibular junction. Hence, the case was diagnosed as persistent hymen and hymenotomy was performed. Result: Upon hymenotomy, about two litres of thick, gummy, tenacious reddish brown colored mucus was evacuated from the vagina. The patency was checked and the animal was treated with antibiotics for three days. The animal was inseminated at the subsequent estrus on the 22nd day and pregnancy was confirmed on 45th day. The animal calved normally and delivered a live male calf. Thus, the borescope could be effectively used in the field of animal reproduction as an alternative tool for the diagnosis of developmental defects in the vagina.

A non-linear transform approach for conduction-radiation heat transfer in the extended thermal discrete element method

Conduction-radiation heat transfer widely exists in nuclear pebble beds, packed beds and powder materials under moderate or high temperatures. Because of the considerable computational cost, it is unrealistic to trace all possible obstructed view factors between spheres in transient particle-scale simulations. With a non-linear transform approach, an extended thermal discrete element method (TDEM) with almost the same computational cost as that required for conduction alone is proposed here. Particle-particle conduction in the contact area, particle-fluid-particle conduction near the contact point and the Knudsen effect under low gas pressures are considered in the determination of the contact thermal resistance (CTR). A particle conduction-radiation scalar is applied in the particle energy balance equation, which is a function of the particle temperature, CTR and radiation exchange factor. The numerical results of the pebble bed are in good agreement with the continuum model and measured results under high temperatures. The temperature transport process in conduction-radiation heat transfer involves anomalous diffusion by discrete and continuum methods. The proposed extended TDEM is proven to be efficient for conduction-radiation heat transfer and feasible to be applied in large-scale computational fluid dynamics (CFD)-DEM simulations.

In Response.

I sincerely thank the authors for describing an experienced-based technique to support the safe tracheal intubation of patients with suspected or confirmed coronavirus disease (COVID-19).1 Their suggestion to use a delayed sequence technique in selected patients is a valuable addition to the “Recommendations for endotracheal intubation of COVID-19 patients.”2 Specifically, they suggest that agitated and uncooperative patients be sedated with ketamine during the preoxygenation phase, to gain their cooperation while minimizing the risk of respiratory depression and cardiovascular instability. The authors describe a difficult and high-stakes scenario. An agitated and uncooperative patient with COVID-19 represents a considerable safety risk to the airway management team. Dislodgement of or damage to personal protective equipment can expose health care providers to the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus. In addition, movement of glasses, goggles, or a face shield can lead to fogging or an obstructed view, which makes tracheal intubation more difficult. Thus, it may be desirable to optimize conditions by sedating certain patients before tracheal intubation. Additional suggestions from others include using a 2-handed technique with the hands in the VE position when using a self-inflating bag-valve-mask device during preoxygenation,3 cross-checking team members’ personal protective equipment (particularly when managing agitated patients), having all needed materials prepared in advance, and knowing the patients’ code status.4 I applaud the authors and others for sharing their lived experiences as we learn together to support patients and each other during the COVID-19 pandemic. Beverley A. Orser, MD, PhDDepartments of Anesthesiology and Pain Medicine and PhysiologyUniversity of TorontoToronto, Ontario, CanadaDepartment of AnesthesiaSunnybrook Health Sciences CentreToronto, Ontario, Canada[email protected]

A Deep Neural Network Model of Particle Thermal Radiation in Packed Bed

Prediction of particle radiative heat transfer flux is an important task in the large discrete granular systems, such as pebble bed in power plants and industrial fluidized beds. For particle motion and packing, discrete element method (DEM) now is widely accepted as the excellent Lagrangian approach. For thermal radiation, traditional methods focus on calculating the obstructed view factor directly by numerical algorithms. The major challenge for the simulation is that the method is proven to be time-consuming and not feasible to be applied in the practical cases. In this work, we propose an analytical model to calculate macroscopic effective conductivity from particle packing structures Then, we develop a deep neural network (DNN) model used as a predictor of the complex view factor function. The DNN model is trained by a large dataset and the computational speed is greatly improved with good accuracy. It is feasible to perform real-time simulation with DNN model for radiative heat transfer in large pebble bed. The trained model also can be coupled with DEM and used to analyze efficiently the directional radiative conductivity, anisotropic factor and wall effect of the particle thermal radiation.

Validation of a Simple Tool for Electronic Documentation of Behavioral Responses to Anesthesia Induction.

Anxiety and distress behaviors during anesthesia induction are associated with negative postoperative outcomes for pediatric patients. Documenting behavioral responses to induction is useful to evaluate induction quality at hospitals and to optimize future anesthetics for returning patients, but we lack a simple tool for clinical documentation. The Induction Compliance Checklist is a tool for grading induction behaviors that is well validated for research purposes, but it is not practical for routine documentation in busy clinical practice settings. The Child Induction Behavioral Assessment tool was developed to provide a simple and easy to use electronic tool for clinical documentation of induction behaviors. The aim of this study was to test the Child Induction Behavioral Assessment tool's concurrent validity with the Induction Compliance Checklist and the interrater reliability. This prospective, observational study included 384 pediatric patients undergoing anesthesia inhalation induction. Concurrent validity with the Induction Compliance Checklist and interrater reliability of the Child Induction Behavioral Assessment were evaluated. Two researchers alternated scoring the Induction Compliance Checklist. The 2 researchers independently scored the Child Induction Behavioral Assessment. The anesthesia clinician caring for the patient also independently scored the Child Induction Behavioral Assessment by completing their routine documentation in the patient's medical record. Two age groups were evaluated (ages 1-3 and 4-12 years old). Clinicians' and researchers' Child Induction Behavioral Assessment scores demonstrated a strong correlation with the Induction Compliance Checklist (P < .0001). There was an excellent agreement between the 2 researchers' Child Induction Behavioral Assessment scores for the younger and older age groups, respectively (Kappa [95% CI] = 0.97 (0.94-0.99); K = 0.94 (0.89-0.99)]. The agreement between the researchers and the 117 clinicians who documented Child Induction Behavioral Assessment assessments in the medical record was good overall (intraclass correlation coefficient = 0.70), with fair agreement with the 1- to 3-year-old patients (intraclass correlation coefficient = 0.56) and good agreement for the 4- to 12-year-old patients (intraclass correlation coefficient = 0.74). The Child Induction Behavioral Assessment scale is a simple and practical electronic tool used to document pediatric behavioral responses to anesthesia inductions. This study provides evidence of the tool's validity and reliability for inhalation inductions. Future research is needed at other hospitals to confirm validity.

Ekonomska opravdanost kabina kranova opremljenih računarskim sistemom vizuelnog navođenja u realnom vremenu

Cranes’ operations are extremely risky and hazardous tasks, as demonstrated in various surveys in the field of incidents’ causes and effects. The most frequent cause of unsafe crane operation task execution is human error. Accordingly, innovation which enables cranes’ safe operations, prevents “blind lifts” and helps crane operator to avoid potential error is urgent. Project SPRINCE has proposed computer-aided Visual Guidance System as a real time solution aimed to prevent crane accidents, caused by obstructed view. This paper analyses the economic feasibility of Visual Guidance System application in various scenarios in aim to connect human, technology and organization issues through cost-benefit framework. There are two proposed investment scenarios analysed: A) Producing and selling of crane cabins with real-time computer-aided Visual Guidance System and B) Usage (purchase) of crane cabins with real-time computer-aided Visual Guidance System. The economic appraisal has proved that the total economic benefit in both scenarios in the complete utilization period is several times higher than the buying price, while the internal rate of return is few times higher than the aggregate rate of interest paid. Also, the amount of time which takes to recover the cost of an investment is less than four years. Moreover, both scenarios belong to the category of innovation projects with very low risk.

An approximation function model for solving effective radiative heat transfer in packed bed

Radiative heat transfer is significant but rather complicated in the bed packed with lots of high temperature particles. Unfortunately, it cannot use traditional radiative transfer equation (RTE) to efficiently predict thermal radiation between particles in packed beds. With continuum assumption, an approximation function model (AFM) is proposed here. A generic physical equation of radiation exchange factor of packed bed is given, which is determined by surface emissivity and particle-scale packing structure. Compared with discrete element method (DEM) simulation, current radiation interaction function (RIF) gives a good estimation of the obstructed view factor of packed bed. The radiation in AFM is equivalent to that of heat conduction at size parameter ξ ≪ 1, and effective thermal conductivity (ETC) in central region of packed bed is higher than that of the whole bed. The AFM is also applicable for pebble bed with both radiative and conductive heat transfer, and it can predict consistent radial temperature distributions with that in experiments. The AFM works as a good replacement of traditional radiative transfer equation (RTE), and is also feasible to apply current equation to analyze other radiation models.

Driver Responses to Incongruent V2V and V2I Safety Critical Information in Left-Turn Across Path Scenarios

The present work aims to help guide the development of safer systems and interfaces by investigating how drivers handle safety messages from in-vehicle and in-roadway infrastructure sources with incongruent onset timing. Two part-task driving simulator experiments were used to examine concurrent Driver-Infrastructure Interface (DII) and Driver-Vehicle Interface (DVI) displays for a gap-assist system while making a Left-Turn Across Path (LTAP) movement at a signalized intersection. Participants encountered repeated LTAP scenarios and indicated whether they would make a left turn through varying gaps in traffic. The key factors examined were: gap size, age, display type, and the visibility of oncoming traffic. Drivers primarily used the displays when they had an obstructed view of oncoming traffic. They preferred the DII, but some participants would rely on the DVI if the DII had conservative timing. Participants showed inconsistent performance when the DII and DVI displayed conflicting information.

An Obstructed View

An Obstructed View

Turning accidents between cars and trucks and cyclists driving straight ahead

Abstract Two projects contain the conflict between turning vehicles and straight ahead driving cyclists. One out of four of all accidents in Germany are accidents with bicycles. In Addition, most of the accidents end with heavy or deathly personal injury. Especially accidents with right turning trucks and straight ahead driving cyclist are on one hand rarely but on the other hand very dangerous because of gravity results of an accident. Finally one of the main problems is the conflict during the driving by green traffic light. Furthermore the obstructed view is a big problem for this accident constellation.

The Cicada Shell, from The Tale of Genji

The Cicada Shell, from The Tale of Genji Lady Murasaki Shikibu (bio) Translated by Charles De Wolf (bio) "Never before have I been so rebuffed!" his Lordship lamented, unable to sleep. "This night I have come to know the cruel nature of the world, and the humiliation is such that I wonder how I may endure." The tears shed by the boy lying beside him only added to his charm. Small and slender, with hair that was not so very long, he bore a poignant resemblance to that other figure his Lordship had held and caressed. Well aware that further pursuit would be most unseemly, his Lordship resigned himself to brooding away the nocturnal hours and sent the youth on no more errands. While it was still dark, he arose and departed, leaving the boy quite forlorn. The lady was not without her own bitter regrets, as there came from his Lordship not a single word. She was not indifferent to his disappointment, and the thought that, with cool-headed resolve he had put an end to his quest, weighed upon her no less than the fear that he would resume his recklessness. Even as she hoped that the entire incident was now behind her, she, too, found herself pensive and restless. As much as his Lordship sought to convince himself that she was hardly a woman with whom he should be concerned, pride alone prevented him from putting her out of his mind. He again turned to the boy: "My misery would be so much less if I came to terms with this debacle, and yet I cannot bear to do so. Go now and find some means by which I may meet her." The task would be daunting, but the lad was pleased to be so honored. He had been waiting in childlike eagerness for an opportunity, when the Governor of Kii was summoned to his province, thereby opening, most conveniently, a penumbral path to the ladies the governor had left behind. The boy took it upon himself to bring his Lordship there in his own carriage. His master might well have fretted about putting himself in the hands of one so young, but there was no time for delay and so, disguised in casual apparel, he hastily went along, anxious to arrive before the closing of the gates. They passed through a little-used entrance, whereupon the boy alighted. To the boy's relief, the men on guard took him for a mere child and showed neither suspicion nor solicitude. He bade his Lordship to wait next to the twin doors at the east side, while he himself went to the south corner and called out in a loud voice, pounding on the shutters before going inside. [End Page 89] "Oh, you are leaving us all exposed to view!" cried one of the women. "Why have you lowered the shutters on such a warm evening?" he replied. "The lady of the west wing has been visiting here since noon. Their ladyships are engaged in Go." Eager for a glimpse, his Lordship stealthily followed in the boy's footsteps and quietly slipped in between a gap in the blinds. The shutters were still open, with a screen immediately before his Lordship folded back. Facing west, he could see that the curtains that should have been in place as a further precaution were instead draped over their stands, perhaps because of the heat, so that all was in plain view. The women were sitting near a lamp, so his Lordship could distinguish there, where she was reclining beside the central pillar, the profile of the one he took to be his heart's desire. She was dressed in what seemed to be twilled undergarments of deep lavender, with a less clearly visible outer robe. Narrow-headed and slender of frame, she was of a demure and modest appearance. Even from her companion she seemed to be concealing her face; except when placing stones on the board, she kept her hands well within her sleeves. The lady's opponent was facing east, thereby giving his Lordship an un - obstructed view of her. Over a white undergarment of gossamer, she wore...