Terahertz Wireless Channels: A Holistic Survey on Measurement, Modeling, and Analysis

Terahertz (0.1-10 THz) communications are envisioned as a key technology for sixth generation (6G) wireless systems. The study of underlying THz wireless propagation channels provides the foundations for the development of reliable THz communication systems and their applications. This article provides a comprehensive overview of the study of THz wireless channels. First, the three most popular THz channel measurement methodologies, namely, frequency-domain channel measurement based on a vector network analyzer (VNA), time-domain channel measurement based on sliding correlation, and time-domain channel measurement based on THz pulses from time-domain spectroscopy (THz-TDS), are introduced and compared. Current channel measurement systems and measurement campaigns are reviewed. Then, existing channel modeling methodologies are categorized into deterministic, stochastic, and hybrid approaches. State-of-the-art THz channel models are analyzed, and the channel simulators that are based on them are introduced. Next, an in-depth review of channel characteristics in the THz band is presented. Finally, open problems and future research directions for research studies on THz wireless channels for 6G are elaborated.Comment: to appear in IEEE Communications Surveys and Tutorial

Working with Grantees: The Keys to Success and Five Program Officers Who Exemplify Them

Successful foundation-grantee relationships hinge on the prowess of individual program officers, whose abilities may vary widely within a single foundation. This research explores what grantees value in their relationships with program officers and identifies four keys to success. Five high-performing program officers share their stories

Speaking for Themselves: Advocates' Perspectives on Evaluation

"Speaking for Themselves: Advocates' Perspectives on Evaluation" will give you a better understanding of advocates' views on evaluation, the advocacy strategies and capacities they find effective, and current evaluation practices. Based on Innovation's Network's research, the report includes recommendations for advocates, funders, and evaluators. Both the research and publication were made possible by the Annie E. Casey Foundation and The Atlantic Philanthropies

Planning for Monitoring, Learning, and Evaluation at Small- to Medium-Sized Foundations

This report is based on findings from desktop research and interviews with selected foundations conducted between April and June 2016. It was developed to give the Oak Foundation a sense of how other foundations are tackling monitoring, evaluation, and learning (MEL) questions, and to show a range of options for Oak to consider as it develops its own MEL Plan. This summary of findings was developed for public distribution, anticipating that it may be useful for other donors.Key trends that emerged from the interviews and desktop research included the following:1. Foundations are spending more resources and putting more staff time into evaluation than they did in the past. Staff at smaller foundations tend to spend more time on individual grant evaluations, while staff at larger foundations tend to spend more time on assessments of broad program areas and on learning processes. While many foundations do not have consistent systems for tracking evaluation spending, some are deciding it would be useful to capture that information more methodically.2. Less attention has been put on learning to-date, but recognition of the importance of purposeful learning is growing quickly. Many foundations are hoping to improve upon their learning processes, but finding that it is not easy. It often requires an internal cultural shift and testing a variety of approaches. In contrast, foundations tend to have fairly clear processes and standards for monitoring and evaluation. Foundations that do have explicit learning efforts remain more focused on internal learning rather than communicating and sharing lessons externally. Foundations tend to be more transparent with external audiences about their grant-making processes, goals, and strategies, and less transparent about how they assess performance or their lessons learned. That said, both grantees and foundations are recognizing that sharing more lessons externally would be beneficial.3. Foundations are exploring appropriate and useful ways to evaluate work done through sub-granting organizations. Some are focusing on building the internal monitoring and evaluation capacity of those organizations. It would be useful for donors to coordinate approaches to evaluate work done through sub-granting organizations, which can allow for pooled resources and avoid putting an extra burden on the subgrantor

Grantees' Limited Engagement with Foundations' Social Media

It is not surprising that foundations are investing in social media tools. These tools can serve myriad functions for foundations, from promoting a culture of transparency to the public at large, to influencing thought leaders, to connecting with grantees

The Foundation Performance Dashboard: Vital Statistics for Social Impact

Boards and foundation leadership rarely have a clear, consistent, and comprehensive picture of their foundation's performance. Interestingly, this situation persists despite the fact that nearly 60% of foundation CEOs would like to have more board involvement in reviewing the foundation's philanthropic mission and effectiveness. Our experience suggests that this conundrum results from a fundamental uncertainty: Foundations are unsure how to bridge the chasm between the readily available and concise metrics for investment performance and the much more complex, expensive, and subjective data from internal operations and program evaluations

Communication and Information Management in the Nonprofit Arts Sector

A survey of a representative sampling of arts organizations finds that their internal and external communication includes a variety of traditional and technological methods, each varying in its preferred usage and perceived effectiveness. While this study was intended to establish a baseline of communication perceptions, behaviors, and impacts, the following conclusions may be reasonably drawn from the survey responses: Communication from arts administrators and organizations, and from others to them, is a major occupier of time. Email in particular dominates average weekly time expenditures.The field's perception of the value and impact of the increased information available to it, and the communication it sends and receives, indicates a struggle with that volume, with a large bloc believing the sheer volume is--or is becoming--unmanageable.While the increase in information being communicated and being received is perceived as having a positive impact on organization productivity, there is a bloc of respondents that believes it is negative on a personal level.Despite the struggle with managing communication of all types and the pervasive feeling among the respondents that there are significant negative impacts on their time and ability to do their jobs, most arts organizations do not have any formal plan to address these issues.Due to the limitations of this survey, it is unclear the extent to which arts organizations are aware of, and are dealing with, communication and information issues, including the challenges posed to staff personnel.Most arts organizations do not have the resources to engage a full-time communications officer.Administrators are challenged to relate the increased information to their specific needs.It may be a myth that executive summaries in reports are the preferred method of reviewing information by arts administrators.For many organizations, this respondent's observation encapsulates the challenge with communication and information management: "We have 20th century resources in a 21st century environment.