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The purpose of this paper is to enable autonomous door-opening with unknown geometrical constraints. Door-opening is a common action needed for mobile manipulators to perform rescue operation. However, it remains difficult for them to handle it in real rescue environments. The major difficulties of rescue manipulation involve contradiction between unknown geometrical constraints and limited sensors because of extreme physical constraints.

A method for estimating the unknown door geometrical parameters using coordinate transformation of the end-effector with visual teleoperation assists is proposed. A trajectory planning algorithm is developed using geometrical parameters from the proposed method.

The relevant experiments are also conducted using a manipulator suited to extreme physical constraints to open a real door with a locked latch and unknown geometrical parameters, which demonstrates the validity and efficiency of the proposed approach.

This is a novel method for estimating the unknown door geometrical parameters with coordinate transformation of the end-effector through visual teleoperation assists.

The purpose of this paper is to extend the usage of stroke gestures in manipulation tasks to make the interaction between human and robot more efficient.

In this paper, a set of stroke gestures is designed for typical manipulation tasks. A gesture recognition and parameter extraction system is proposed to exploit the information in stroke gestures drawn by the users.

The results show that the designed gesture recognition subsystem can reach a recognition accuracy of 99.00 per cent. The parameter extraction subsystem can successfully extract parameters needed for typical manipulation tasks with a success rate about 86.30 per cent. The system shows an acceptable performance in the experiments.

Using stroke gesture in manipulation tasks can make the transmission of human intentions to the robots more efficient. The proposed gesture recognition subsystem is based on convolutional neural network which is robust to different input. The parameter extraction subsystem can extract the spatial information encoded in stroke gestures.

The author designs stroke gestures for manipulation tasks which is an extension of the usage of stroke gestures. The proposed gesture recognition and parameter extraction system can make use of stroke gestures to get the type of the task and important parameters for the task simultaneously.

The purpose of the paper is to share a perspective new to the author, regarding how acquisitions problems in the library grow and present themselves.

The paper considers possible ways to prevent problems and minimize time spent solving them.

Filing, establishing standard operating procedures, and delegating problems might eliminate or prevent some problems, but unexpected staff shortages and intermittent or unusual problems will continue to occur.

It is hoped that the realization that not every situation can be anticipated will help faculty and staff be more patient with their colleagues in the library.

When the mobile manipulator is traveling on an unconstructed terrain, the external disturbance is generated. The load on the end of the mobile manipulator will be affected strictly by the disturbance. The purpose of this paper is to reject the disturbance and keep the end effector in a stable pose all the time, a control method is proposed for the onboard manipulator.

In this paper, the kinematics and dynamics models of the end pose stability control system for the tracked robot are built. Through the guidance of this model information, the control framework based on active disturbance rejection control (ADRC) is designed, which keeps the attitude of the end of the manipulator stable in the pitch, roll and yaw direction. Meanwhile, the control algorithm is operated with cloud computing because the research object, the rescue robot, aims to be lightweight and execute work with remote manipulation.

The challenging simulation experiments demonstrate that the methodology can achieve valid stability control performance in the challenging terrain road in terms of robustness and real-time.

This research facilitates the stable posture control of the end-effector of the mobile manipulator and maintains it in a suitable stable operating environment. The entire system can normally work even in dynamic disturbance scenarios and uncertain nonlinear modeling. Furthermore, an example is given to guide the parameter tuning of ADRC by using model information and estimate the unknown internal modeling uncertainty, which is difficult to be modeled or identified.

To examine the relative roles played by cognition and emotion in the development of customer satisfaction in a retail setting.

An experimental design was employed. Study participants were exposed one of two expectation scenarios depicting past experience with an unnamed retail store, with one developed to build high expectations and one developed to create low expectations. Study participants were then exposed to one of two performance scenarios depicting a new experience with the unnamed retail store, with one depicting a successful pleasurable experience and one depicting a performance failure. Participants were also asked to complete scales measuring their cognitive evaluation of the perceived performance and their emotional reaction to the perceived performance.

Both cognitive evaluation and emotional reaction were found to explain the level of satisfaction experienced in a retail setting. As opposed to a service setting, however, cognitive evaluation was found to be more important than emotional reaction in explaining customer satisfaction. When the individual treatment levels were examined, anger/delight and shame were observed to be significant only for the third treatment level (high expectations/poor performance).

The findings suggest that retailers whose customers possess high expectations will need to place explicit attention on their customers' emotions. If a performance is deemed as negative, not only will the negative performance affect level of satisfaction, but also the negative emotions associated with the poor performance will also likely affect level of satisfaction.

The paper examines the role of emotion in developing customer satisfaction in a retail setting.

In features based design systems that are underpinned by solid models, buildings are designed by applying features to the design domain. A feature may be translated and/or rotated in order to position it in the desired place. Contradiction between the applied features and resulting features may occur due to the features interaction, wrong positioning, or inadequate parameters supplied by the user during the product definition. Moreover, the application of other features may cause some features to degenerate to further features. Therefore, verification of the resulting features must be performed against the applied features to establish whether the resulting features conform to the underlying geometry. Current feature‐based design systems employ a mechanism of tagging feature labels onto geometry. This approach does not guarantee the geometric correctness of the resultant feature and knowledge of the topology of the resulting feature and a geometric analysis is necessary to correctly identify the validity of the resultant feature. The research reported in this paper proposes an alternative approach which uses a product model that permits all geometrical and technological information associated with the design and construction stages to be represented. Individual features can be extracted from the product model and analysed to determine their accessibility. Methods which use the product description and other construction data to determine feature validity, accessibility and machinability are used. Each volumetric feature corresponds to a solid that can be added by one or more construction process or removed by one or more machining operations; as a consequence of applying volumetric features, surface features are generated. These surface features provide enough information to enable the accessibility, and machinability of the individual features to be determined and establish the possible routes in which the feature can be accessed if any.

Many work conditions require manipulators to open cabinet doors and then gain access to the desired workspace. However, after opening, the unlocked doors can easily close, interrupt a task and potentially break the operating end-effectors. This paper aims to address a manipulator's behavior planning problem for responding to a dynamic workspace released by door opening.

A dynamic model of the restricted workspace released by an unlocked door is established. As a whole system to treat, the interactions between the workspace and robot are analyzed by using a partially observable Markov decision process. A self-protective policy decision executed as a belief tree is proposed. To respond to the policy, this study has designed three types of actions: stay on guard in the workspace, using an elbow joint to defense the door and linear escape out of the workspace for self-protection by observing collision risk levels to trigger them. Finally, this study proposes self-protective motion controllers based on risk time optimization to act to the planned actions.

The elbow defense could balance robotic safety and work efficiency by interrupting the end-effector's work and using the elbow joint to prevent the door-closing in an active collision way. Compared with the stay and escape action, the advantage of the elbow defense is having a predictable performance to quick callback the interrupted work after the risk was relieved.

This work provides guidance for the safe operation of a class of robot operations and the upgrade of motion planning.

This paper discusses an approach for constructing product models in terms of features. In particular, the work focused on features verification and their accessibility using the solid model representation of the design. The research was motivated by the inadequacy of the current geometric modellers to perform verification and accessibility analyses, resulting in possible contradictions between the intended and the resultant features. Consequently, the wrong data are passed to the applications that use the data. The paper describes an alternative approach that considers the geometry, topology of the design and other construction and engineering information of the product rather than the simplistic approach, which is implemented in many geometric modellers; and is based on tagging feature labels on geometry. Individual features are extracted from the product model, where all the information about the product is held, for analyses. Each volumetric feature corresponds to a solid. As a consequence of applying volumetric features to the design model, surface features are generated. These surface features provide enough information to enable the validity and accessibility of the individual features to be determined and establish the possible routes in which the feature can be accessed, if any. The algorithms that are used to determine the validity and accessibility of features will be discussed.

The effects of dust exposure in buildings and its health and comfort consequences continue to concern occupants, particularly those who spend most of their time indoors. This study examines the influence of building opening characteristics on surface dust loading in indoor environments to determine the dust particles' impact on different opening configurations.

Indoor Harmattan dust surface loading data were collected from Maiduguri, Northeastern Nigeria, using model rooms with six different window configurations. A simple mathematical relationship was employed to assess surface dust loading characteristics in the model rooms. The study measured dust thrice between December and February for three days (72 h). The results were analyzed using descriptive statistics.

The results determined the highest average surface dust loading of 12.03 g/m2 in the room with awning windows at an indoor-to-outdoor (I/O) ratio of 0.7. In contrast, the experiment in the room with a closed window recorded the lowest average surface dust loading of 5.24 g/m2 at an I/O ratio of 0.30, which is infiltration. The outcomes further indicate that the average surface dust loading varies with the building opening type and position, as higher surface dust loadings were recorded in locations closer to the openings (doors and windows), reaffirming that the dominant source of the dust particles is outdoors. According to the study, dust incursion due to infiltration accounts for 30% of the outdoor surface loading.

Thus, Harmattan dust is a serious challenge to the health, productivity and hygiene of building occupants in the study area. The built-environment professionals must use the study's outcome to optimize building openings' designs (shape, size and form) for effective indoor dust control.

Design policy and regulations within our cities can significantly impact the accessibility and social participation of people with disability. Whilst public, wheelchair-accessible bathrooms are highly regulated spaces for this reason, very little is known about how wheelchair users use them or what wheelchair users think of current design standards.

This exploratory inquiry adopts an embodied approach to investigate the perspectives of powered and manual wheelchair users on public bathroom usage and design. The study encompasses twelve interviews, delving into how participants utilise accessible bathrooms based on mobility, disability, support levels, wheelchair types, urinary/bowel regimes and catheter use.

A thorough analysis of individual public bathroom elements (layout, toilet, handwashing and grab rails) discussed in the interviews reveals themes of safety, hygiene, planning/avoidance and privacy and dignity. Strikingly, many wheelchair users invest significant effort in planning for bathroom use or avoid public bathrooms altogether. The ongoing maintenance and regular cleaning of bathrooms, something not captured in regulatory standards, has been highlighted as something of critical importance to the ongoing accessibility and safety of public bathrooms for wheelchair users. This points to a relationship between the design and the maintenance of public bathrooms as influencers of health, well-being, community inclusion and the social participation of people with disability.

This qualitative research is exploratory and contributes to a growing body of evidence that explores how public spaces are experienced by diverse members of our communities, including people with disability. To date, there have been very few investigations into the embodied perspectives of wheelchair users about public bathroom design.

The findings can potentially drive innovative and inclusive approaches to bathroom design regulations that include operational and maintenance guidance.

The research aims to inform design regulations, standards development and practices of designers, architects, facilities managers, developers and planners, ensuring public spaces are designed to support more accessible, inclusive and socially sustainable cities.

Whilst wheelchair-accessible bathrooms have been designed and constructed for public use (in many countries) for many years, we know very little about how wheelchair users actually use them or what wheelchair users think of current design standards.