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The Lady Be Good: A Case Study in Radio Frequency Direction Finders
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| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 172-176 |
| Abstrak | : | Over the past several years, we have contributed articles to TPT that focus on a forensics-style reexamination of significant historical events. The purpose of these articles is to afford students the opportunity to apply basic principles of physics to unsolved mysteries and potentially settle the historical debate. We assembled the lessons learned and best practices of our activities into a formalized pedagogy for teaching topics in physics, engineering, problem solving, critical thinking, and ethics. |
Translational Potential of Neuroimaging Genomic Analyses to Diagnosis and Treatment in Mental Disorders
| Pengarang | : | Jiayu Chen |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 5) |
| Halaman | : | 912-927 |
| Abstrak | : | Imaging genomics focuses on characterizing genomic influence on the variation of neurobiological traits, holding promise for illuminating the pathogenesis, reforming the diagnostic system, and precision medicine of mental disorders. This paper aims to provide an overall picture of the current status of neuroimaging-genomic analyses in mental disorders, and how we can increase their translational potential into clinical practice. The review is organized around three perspectives: 1) toward reliability, generalizability, and interpretability, where we summarize the multivariate models and discuss the considerations and tradeoffs of using these methods and how reliable findings may be reached, to serve as ground for further delineation; 2) toward improved diagnosis, where we outline the advantages and challenges of constructing a dimensional transdiagnostic model and how imaging genomic analyses map into this framework to aid in deconstructing heterogeneity and achieving an optimal stratification of patients that better inform treatment planning; and 3) toward improved treatment. Here, we highlight recent efforts and progress in elucidating the functional annotations that bridge between genomic risk and neurobiological abnormalities, in detecting genomic predisposition and prodromal neurodevelopmental changes, as well as in identifying imaging genomic biomarkers for predicting treatment response. Providing an overview of the challenges and promises, this review hopefully motivates imaging genomic studies with multivariate, dimensional, and transdiagnostic designs for generalizable and interpretable findings that facilitate the development of personalized treatment. |
Projectile Motion: The “Coming and Going” Phenomenon
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 168-171 |
| Abstrak | : | During elementary physics courses, many examples in mechanics are studied without considering air resistance effects. We can mention, for example, projectile motion and free fall, among many others. Only brief studies of such systems in classical mechanics courses consider linear air resistance (Fdrag ∝ v), which is the simplest model to account for the drag effect by modeling objects moving in viscous media with small velocities (more precisely, small Reynolds number). Quadratic air resistance (Fdrag ∝ v2), which applies for objects moving in resistive media with high velocities (high Reynolds number), is hardly mentioned, but it can be found in many papers. However, in nature air resistance plays a big role in the motion of bodies and so it must be included when studying any kind of phenomena related to mechanics. |
Demonstration to Show Resonant Oscillations of a Simple Pendulum Coupled to a Mass-Spring Oscillator
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 166-167 |
| Abstrak | : | Resonance is a widely observed physical phenomenon, occurring when an oscillator experiences a driving force whose frequency closely matches one of its own natural frequencies. Due to its broad applicability in physics, resonance is a familiar topic in the physics teaching literature. Previous studies include resonant energy transfer between similar mechanical systems such as coupled pendulums, resonant oscillations of wine glasses driven by sound waves, and resonance in AC circuits. Moreover, special drivers have been constructed to produce resonant oscillations of a variety of mechanical systems. |
Student Responses to Changes in Introductory Physics Learning Due to the COVID-19 Pandemic
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 162-165 |
| Abstrak | : | As a result of the spread of COVID-19 during spring 2020, many colleges and universities across the U.S., and beyond, were compelled to move entirely to remote, online instruction, or shut down. Due to the rapidity of this transition, instructors had to significantly—if not completely—change their instructional style on very short notice. Our purpose with this paper is to report on student experiences and reactions to the switch to emergency remote learning at two large land-grant, research-intensive universities. We aimed to explore how students have received and dealt with the shift to remote learning that began in March 2020, specifically in introductory physics and astronomy courses. By providing timely student feedback, we hope to help instructors tune their efforts to build a more effective remote learning environment. |
Aeronautical Ad Hoc Networking for the Internet-Above-the-Clouds
| Pengarang | : | Jiankang Zhang |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 5) |
| Halaman | : | 868-911 |
| Abstrak | : | The engineering vision of relying on the “smart sky” for supporting air traffic and the “internet-above-the-clouds” for in-flight entertainment has become imperative for the future aircraft industry. Aeronautical ad hoc networking (AANET) constitutes a compelling concept for providing broadband communications above clouds by extending the coverage of air-to-ground (A2G) networks to oceanic and remote airspace via autonomous and self-configured wireless networking among commercial passenger airplanes. The AANET concept may be viewed as a new member of the family of mobile ad hoc networks (MANETs) in action above the clouds. However, AANETs have more dynamic topologies, larger and more variable geographical network size, stricter security requirements, and more hostile transmission conditions. These specific characteristics lead to more grave challenges in aircraft mobility modeling, aeronautical channel modeling, and interference mitigation as well as in network scheduling and routing. This paper provides an overview of AANET solutions by characterizing the associated scenarios, requirements, and challenges. Explicitly, the research addressing the key techniques of AANETs, such as their mobility models, network scheduling and routing, security, and interference, is reviewed. Furthermore, we also identify the remaining challenges associated with developing AANETs and present their prospective solutions as well as open issues. The design framework of AANETs and the key technical issues are investigated along with some recent research results. Furthermore, a range of performance metrics optimized in designing AANETs and a number of representative multiobjective optimization algorithms are outlined. |
Exploring Hubble Constant Data in an Introductory Course
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 159-161 |
| Abstrak | : | Popular accounts of exciting discoveries often draw students to physics and astronomy, but at the introductory level it is challenging to connect with these in a meaningful way. The use of real astronomical data in the classroom can help bridge this gap and build valuable quantitative and scientific reasoning skills. This paper presents a strategy for studying Hubble’s law and the accelerating expansion of the universe using actual data. Along with understanding the physical concepts, an explicit goal is to develop skills for analyzing data in terms of a model. |
Have Astronomers Found a Star Older Than the Universe?
| Pengarang | : | Don Lincoln |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 154-158 |
| Abstrak | : | The theory of the Big Bang is accepted nearly universally among the scientific community. However, there is a small cadre of individuals who dispute this consensus and they point to a handful of datums that don’t fit into the picture. One such datum is the existence of a star with an age reported to be older than the cosmos itself. This star is called the Methuselah star, named after the biblical patriarch. Obviously, if the age of this star is truly older than the universe, it would be a discovery of considerable concern to those who accept Big Bang cosmology. In the following text, I describe the debate, beginning with a brief historical treatment of the early discoveries. I have made this choice because the early papers are easy to understand and are accessible suggested reading for introductory students interested in the origins of some of the key evidence supporting the Big Bang. |
Zero Is Something
| Pengarang | : | Arthur Eisenkraft |
| Nama Majalah/Jurnal | : | The Physics Teacher |
| Volume / Edisi | : | 59 (No. 3) |
| Halaman | : | 151-153 |
| Abstrak | : | In everyday language, “zero” and “nothing” are generally synonyms if not interchangeable. In physics, however, these two terms are quite distinct. Zero often refers to a number and nothing often refers to the vacuum state. Furthermore, the number zero has a variety of different meanings, among which physics teachers shift flexibly and effortlessly. This article informally describes some of the difficulties associated with the choice of zero in the context of gravitational potential energy, and relates an instructional approach that facilitates students’ understanding. |
Seeing Across Oceans: John Logie Baird’s 1928 Trans-Atlantic Television Demonstration [Scanning Our Past]
| Pengarang | : | - |
| Nama Majalah/Jurnal | : | Proceedings of the IEEE |
| Volume / Edisi | : | 107 (No. 6) |
| Halaman | : | 1206-1218 |
| Abstrak | : | The earliest demonstrations of television in the mid-1920s showed little more than the principle of seeing by electricity, often over no greater distance than between rooms in a building. At the time, ideas from the 19th century centered around mechanical scanning were the only means available to produce television. The advent of the vacuum tube in the early 1920s made it possible for those ideas to be put into practice. This article explores the circumstances and significance of John Logie Baird's achievement of bridging the Atlantic by television in 1928. This is contrasted in technical detail, performance, and social impact with the earlier demonstration of television by AT&T/Bell Labs |