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Imitation learning is a powerful tool for planning the trajectory of robotic end-effectors in Cartesian space. Present methods can adapt the trajectory to the obstacle; however, the solutions may not always satisfy users, whereas it is hard for a nonexpert user to teach the robot to avoid obstacles in time as he/she wishes through demonstrations. This paper aims to address the above problem by proposing an approach that combines human supervision with the kernelized movement primitives (KMP) model.

This approach first extracts the reference database used to train KMP from demonstrations by using Gaussian mixture model and Gaussian mixture regression. Subsequently, KMP is used to modulate the trajectory of robotic end-effectors in real time based on feedback from its interaction with humans to avoid obstacles, which benefits from a novel reference database update strategy. The user can test different obstacle avoidance trajectories in the current task until a satisfactory solution is found.

Experiments performed with the KUKA cobot for obstacle avoidance show that this approach can adapt the trajectories of the robotic end-effector to the user’s wishes in real time, including trajectories that the robot has already passed and has not yet passed. Simulation comparisons also show that it exhibits better performance than KMP with the original reference database update strategy.

An interactive learning approach based on KMP is proposed and verified, which not only enables users to plan the trajectory of robotic end-effectors for obstacle avoidance more conveniently and efficiently but also provides an effective idea for accomplishing interactive learning tasks under constraints.

Many existing trajectory optimization algorithms use parameters like maximum velocity or acceleration to formulate constraints. Due to the ignoring of the quadrotor actual tracking capability, the generated trajectories may not be suitable for tracking control. The purpose of this paper is to design an online adjustment algorithm to improve the overall quadrotor trajectory tracking performance.

The authors propose a reference trajectory resampling layer (RTRL) to dynamically adjust the reference signals according to the current tracking status and future tracking risks. First, the authors design a risk-aware tracking monitor that uses the Frenét tracking errors and the curvature and torsion of the reference trajectory to evaluate tracking risks. Then, the authors propose an online adjusting algorithm by using the time scaling method.

The proposed RTRL is shown to be effective in improving the quadrotor trajectory tracking accuracy by both simulation and experiment results.

Infeasible reference trajectories may cause serious accidents for autonomous quadrotors. The results of this paper can improve the safety of autonomous quadrotor in application.

The purpose of this paper is to provide an overview of how reference service is provided in the 3D virtual world, Second Life (SL), and to further the professional understanding of the newest reference “frontier” and its impact on the library reference world.

A survey study was conducted to examine the nature and practice of reference service provided by volunteer reference practitioners in SL. Different aspects of SL reference were studied, including types of reference questions, types of reference sources, communication methods, reference competencies and differences between SL reference and real life reference.

The paper reveals that, as an independent service point, the SL reference desk serves mostly SL‐related information needs and reference librarians rely heavily on their personal knowledge to answer users' questions. One distinct feature of the SL reference desk is its social nature. It functions both as a place for social gathering and a place for information and reference service.

This study investigates various aspects of SL reference service and introduces the new reference development to a larger audience. Findings from this study will help practitioners who are interested in adopting new technologies in reference work obtain a thorough understanding of SL reference and its value to their respective communities, and hence, design better virtual services for users.

This study is the first study to systematically examine reference activities in SL and present in‐depth views on the nature and practice of SL reference.

In the literature of librarianship, the education of a reference librarian has, on the whole, meant two things. First, it has referred to the theoretical and/or practical training in reference services that a student receives in library school. Second, it has meant the training, or lack of it, the new librarian receives in making the transition from library school to the reference desk. What reference education has not meant, to judge by the literature, is the ongoing training or professional development a working reference librarian might receive on the job.

This paper aims to examine Patrick Wilson’s 1977 essay, Public Knowledge, Private Ignorance, which emphasizes practice rooted in theory. Modern reference work ought to look back to this 35-year-old essay to be reminded of the intent of reference practice by considering Wilson’s discussion.

This paper examines Wilson’s decades-old thesis and applies it to reference work and reference resources for today’s information professionals.

The crux of Wilson’s essay remains relevant today when applied to reference work and information-seeking.

This essay leaves readers with practical tips for reference work rooted in theory, and also expands on Wilson’s 1977 essay from a contemporary viewpoint, providing guidance for modern reference librarianship.

Communication between reference librarians is vital for the provision of enhanced reference services. This article discusses the creation and application of three Web‐based tools that allow librarians to offer quick answers to questions posed on the library’s e‐mail reference service, to easily share news and ideas with each other between reference desk shifts, and to be actively involved in the scheduling of reference desk shifts.

To provide an overview of the reference services provided through the use of Tablet PCs at the Salem‐South Lyon District Library.

A detailed description of what Tablet PCs are and how they work, including information about the benefits Tablet PCs present to reference transactions and tips for librarians to successfully integrate Tablet PCs into their reference service.

Tablet PCs allow reference librarians to provide quality customer service to their patrons by saving them time. Librarians who use Tablet PCs during reference transactions have access to online resources from any point in a library’s wireless network.

There are new models of Tablet PCs available on the market that may not have been tested by librarians. New, improved features of Tablet PCs may enhance their usefulness to librarians.

This paper provides useful information and advice for librarians who are considering using Tablet PCs, or who are searching for a way to enhance their current reference service.

This paper provides insight from librarians who are currently using Tablet PCs in their reference service. This will inspire other librarians to consider using Tablet PCs in their libraries and help them be successful in the integration of Tablets into their reference routines.

The proliferation of electronic sources in reference departments has made them increasingly important in providing reference service to library patrons. These sources include the online public access catalog, electronic databases (both indexes and full‐text databases), and the Internet. Much has been written on evaluation of reference librarians in the traditional areas of reference desk service, the use of print sources, and bibliographic instruction. Discusses the establishment of guidelines for assessment of reference librarians’ effectiveness in providing service to patrons using electronic sources and methods of assessing individual effectiveness.