From Pose to Tales of the City, there's a slew of content telling new stories about the LGBTQ+ rights movement.
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Intro Video
Tuesday, June 11, 2019
New Space Telescopes Could Look Like Giant Beach Balls
Fans Are Better Than Tech at Organizing Information Online
New York City street named for rapper Notorious B.I.G.
A New York City street has been named for rapper Notorious B.I.G.
Community members and elected officials gathered in a downpour on Monday at the intersection of St. James Place and Fulton Street.
Rapper Lil’ Kim — embracing the event’s themes of social justice and making a difference — exclaimed: “We did it, Brooklyn!”
B.I.G., who was born Christopher Wallace, was shot to death in Los Angeles in 1997.
He detailed street life in Brooklyn in songs and on albums that dominated the pop charts.
Voletta Wallace recalled telling a friend amid her heartbreak: “My son was well loved.”
But she said the street naming evoked “happy tears.”
The post New York City street named for rapper Notorious B.I.G. appeared first on theGrio.
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Botswana decriminalises homosexuality in landmark ruling
Caster Semenya named in South Africa's preliminary squad for World Championships
Monday, June 10, 2019
Algorithm tells robots where nearby humans are headed
In 2018, researchers at MIT and the auto manufacturer BMW were testing ways in which humans and robots might work in close proximity to assemble car parts. In a replica of a factory floor setting, the team rigged up a robot on rails, designed to deliver parts between work stations. Meanwhile, human workers crossed its path every so often to work at nearby stations.
The robot was programmed to stop momentarily if a person passed by. But the researchers noticed that the robot would often freeze in place, overly cautious, long before a person had crossed its path. If this took place in a real manufacturing setting, such unnecessary pauses could accumulate into significant inefficiencies.
The team traced the problem to a limitation in the robot’s trajectory alignment algorithms used by the robot’s motion predicting software. While they could reasonably predict where a person was headed, due to the poor time alignment the algorithms couldn’t anticipate how long that person spent at any point along their predicted path — and in this case, how long it would take for a person to stop, then double back and cross the robot’s path again.
Now, members of that same MIT team have come up with a solution: an algorithm that accurately aligns partial trajectories in real-time, allowing motion predictors to accurately anticipate the timing of a person’s motion. When they applied the new algorithm to the BMW factory floor experiments, they found that, instead of freezing in place, the robot simply rolled on and was safely out of the way by the time the person walked by again.
“This algorithm builds in components that help a robot understand and monitor stops and overlaps in movement, which are a core part of human motion,” says Julie Shah, associate professor of aeronautics and astronautics at MIT. “This technique is one of the many way we’re working on robots better understanding people.”
Shah and her colleagues, including project lead and graduate student Przemyslaw “Pem” Lasota, will present their results this month at the Robotics: Science and Systems conference in Germany.
Clustered up
To enable robots to predict human movements, researchers typically borrow algorithms from music and speech processing. These algorithms are designed to align two complete time series, or sets of related data, such as an audio track of a musical performance and a scrolling video of that piece’s musical notation.
Researchers have used similar alignment algorithms to sync up real-time and previously recorded measurements of human motion, to predict where a person will be, say, five seconds from now. But unlike music or speech, human motion can be messy and highly variable. Even for repetitive movements, such as reaching across a table to screw in a bolt, one person may move slightly differently each time.
Existing algorithms typically take in streaming motion data, in the form of dots representing the position of a person over time, and compare the trajectory of those dots to a library of common trajectories for the given scenario. An algorithm maps a trajectory in terms of the relative distance between dots.
But Lasota says algorithms that predict trajectories based on distance alone can get easily confused in certain common situations, such as temporary stops, in which a person pauses before continuing on their path. While paused, dots representing the person’s position can bunch up in the same spot.
“When you look at the data, you have a whole bunch of points clustered together when a person is stopped,” Lasota says. “If you’re only looking at the distance between points as your alignment metric, that can be confusing, because they’re all close together, and you don’t have a good idea of which point you have to align to.”
The same goes with overlapping trajectories — instances when a person moves back and forth along a similar path. Lasota says that while a person’s current position may line up with a dot on a reference trajectory, existing algorithms can’t differentiate between whether that position is part of a trajectory heading away, or coming back along the same path.
“You may have points close together in terms of distance, but in terms of time, a person’s position may actually be far from a reference point,” Lasota says.
It’s all in the timing
As a solution, Lasota and Shah devised a “partial trajectory” algorithm that aligns segments of a person’s trajectory in real-time with a library of previously collected reference trajectories. Importantly, the new algorithm aligns trajectories in both distance and timing, and in so doing, is able to accurately anticipate stops and overlaps in a person’s path.
“Say you’ve executed this much of a motion,” Lasota explains. “Old techniques will say, ‘this is the closest point on this representative trajectory for that motion.’ But since you only completed this much of it in a short amount of time, the timing part of the algorithm will say, ‘based on the timing, it’s unlikely that you’re already on your way back, because you just started your motion.’”
The team tested the algorithm on two human motion datasets: one in which a person intermittently crossed a robot’s path in a factory setting (these data were obtained from the team’s experiments with BMW), and another in which the group previously recorded hand movements of participants reaching across a table to install a bolt that a robot would then secure by brushing sealant on the bolt.
For both datasets, the team’s algorithm was able to make better estimates of a person’s progress through a trajectory, compared with two commonly used partial trajectory alignment algorithms. Furthermore, the team found that when they integrated the alignment algorithm with their motion predictors, the robot could more accurately anticipate the timing of a person’s motion. In the factory floor scenario, for example, they found the robot was less prone to freezing in place, and instead smoothly resumed its task shortly after a person crossed its path.
While the algorithm was evaluated in the context of motion prediction, it can also be used as a preprocessing step for other techniques in the field of human-robot interaction, such as action recognition and gesture detection. Shah says the algorithm will be a key tool in enabling robots to recognize and respond to patterns of human movements and behaviors. Ultimately, this can help humans and robots work together in structured environments, such as factory settings and even, in some cases, the home.
“This technique could apply to any environment where humans exhibit typical patterns of behavior,” Shah says. “The key is that the [robotic] system can observe patterns that occur over and over, so that it can learn something about human behavior. This is all in the vein of work of the robot better understand aspects of human motion, to be able to collaborate with us better.”
This research was funded, in part, by a NASA Space Technology Research Fellowship and the National Science Foundation.
from MIT News http://bit.ly/2IwzZEY
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A platform for Africa’s mobile innovators
Sam Gikandi ’05 SM ’06 and Eston Kimani ’05 have always believed in the potential of Africa’s entrepreneurial community. Their years at MIT, beginning in 2001 when they left their home country of Kenya, only reinforced that belief.
Through the MIT-Africa initiative and other campus programs that allowed them to work in regions across the African continent, they met hundreds of established and aspiring software developers, many of whom were in various stages of starting companies.
In order for these developers to maximize their impact, Gikandi and Kimani knew they’d need to reach the hundreds of millions of Africans who own cell phones but not smartphones. That has traditionally required entrepreneurs to go through several long and complex processes, including applying for access to telecommunications infrastructure from mobile operators, setting up the necessary technical integrations, and gaining approval from regulatory agencies in each region they wanted to operate in.
Gikandi and Kimani felt those hurdles were holding Africa’s businesses back, so they founded Africa’s Talking to unleash entrepreneurs’ full potential.
Since 2012, the company, known colloquially as AT, has been helping businesses in Africa communicate and transact with customers — whether they have a smartphone or not — through text, voice, and other mobile-centered application programming interfaces, or APIs.
The APIs act as plug-and-play capabilities for developers to quickly add mobile features, including the ability to send and receive payments, to their solution. Gikandi describes the company as “telecom in a box.”
Africa’s Talking currently operates in 18 countries around Africa and supports about 5,000 businesses ranging from early-stage startups to large organizations. Businesses can add APIs as new needs arise and pay as they go, dramatically reducing the risks and time commitment traditionally associated with telecom integrations.
This spring, the company launched AT Labs, which aims to leverage its network, expertise, and infrastructure to help entrepreneurs create impactful companies in the shortest possible timeframe.
Gikandi, who ceded his CEO role at Africa’s Talking to lead AT Labs, says the new program will take a small stake in the companies it supports. But he also wants to incentivize founders to give back to AT Labs once they’ve had success.
He says the business model is in line with the larger symbiotic relationship between Africa’s Talking and its customers, in which all parties feed off of each other’s success: “We have a big advantage with Africa’s Talking, but we feel we only grow when the local ecosystem grows.”
Removing barriers to innovation
The rise in cell phone ownership among Africans over the last 15 years has given entrepreneurs the opportunity to create transformative solutions on the continent. But Gikandi says telecom companies make the process of gaining access to their infrastructure very difficult, sometimes forcing entrepreneurs to obtain multiple contracts for the same service or denying their requests outright.
“That’s basically a full-time business in itself,” Gikandi says of gaining approvals from telecom companies. “A lot of innovation wasn’t happening because developers didn’t see how they could leverage that infrastructure. We really lowered the barrier.”
Now, if an entrepreneur builds a financial lending solution, for example, they might use AT’s texting API to allow people to register for the service through an SMS message. The entrepreneur may then use another AT API, known as Unstructured Supplementary Service Data (USSD), to gather more information (think of prompts such as “Reply X for more information on Y”). After a customer is registered, it could be useful to send them text- or voice-based payment reminders. And AT’s payments API makes it easy for businesses to send and receive money through text messages, a powerful tool for working with the millions of Africans without bank accounts.
Africa’s Talking even offers businesses a call center and an analytics platform for tracking customer contacts and engagement.
“The developers just have to tap into AT, and then we can coordinate [everything],” Gikandi says. “The developers can outsource their telecom infrastructure to AT and just focus on their core business.”
Scaling for impact
Gikandi says Africa’s Talking is still in growth mode after raising an $8.6 million funding round last year. Since 2016, the company has had a presence in several countries in east Africa and in Nigeria. The new funds have allowed it to spread into southern Africa (including in Zimbabwe, Zambia, South Africa, and Botswana) and west Africa (including Côte d’Ivoire and Senegal).
It can be difficult for entrepreneurs in the West to appreciate just how huge these markets are: At around 1.2 billion people, Africa’s population is nearly equal to the populations of Europe and North America combined. Each country Africa’s Talking expands to brings a wave of entrepreneurs eager to improve lives with innovative, mobile-based solutions.
“We think it’s really powerful,” Gikandi says. “Let’s say we add a new payment integration in Nigeria. You could then run your business in Nigeria without changing anything in your core business. It creates economies of scale, and allows businesses to focus on what’s important: The value they’re delivering to their customers.”
In Februrary, Gikandi handed his CEO role at Africa’s Talking over to longtime chief operating officer Bilha Ndirangu ’06. Gikandi says he knows Ndirangu can continue growing the company while he puts more time into AT Labs, which is still in the early stages of building its incubator-like support model. For AT Labs, Gikandi envisions a studio that brings people with ideas together with technical talent, infrastructure, and business expertise.
With both Africa’s Talking and AT Labs, Gikandi’s goal is to support the African continent by tapping into its most valuable resource: its people.
“Africa is full of industry and consumers,” Gikandi says. “So the goal is to create a single platform where entrepreneurs can access the entire African market.”
from MIT News http://bit.ly/2Wu9Hb2
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Oberlin College must pay $11 million after jury claims it wrongly accused bakery of racism
The family behind an Ohio bakery has won an $11 million judgement against Oberlin College claiming they suffered backlash from its staff and students amid racism charges.
—Where are they now? Key players in O.J. Simpson murder trial 25 years after the trial of the century—
The owners of Gibson’s Bakery and Market says it was libeled and wrongfully accused of racially profiling students and a Ohio jury reportedly agreed last week.
Three Black students were arrested in November 2016 for allegedly trying to “steal wine or otherwise illegally obtain wine” from the bakery, according to a defamation lawsuit.
From those arrests the school community, including deans and professors, protested against the bakery and accused it of being racist, according to CNN.
The boycotts, the lawsuit states, had a “devastating effect on Gibson’s Bakery and the Gibson family” after students and community members were urged not to shop at their business.
The school’s Vice President and Dean of Students Meredith Raimondo and other college staff members “handed out hundreds of copies” of a flier that stated the bakery had racially profiled its students, the lawsuit states.
The flier specifically told people “DON’T BUY” from Gibson’s Bakery, according to the suit.
“This is a RACIST establishment with a LONG ACCOUNT of RACIAL PROFILING and DISCRIMINATION,” the flier read, the lawsuit said.
The lawsuit also states the bakery suffered damage due to the school promoting 10 other bakeries in the area and telling people that it had severed its business relationship with the bakery.
A jury on Friday, found Oberlin College liable for defamation, infliction of intentional emotional distress and intentional interference of business relationships.
Donica Thomas Varner, Oberlin vice president and general counsel, wrote in a statement about the verdict:
“We are disappointed with the verdict and regret that the jury did not agree with the clear evidence our team presented,” the letter said.
“Neither Oberlin College nor Dean Meredith Raimondo defamed a local business or its owners, and they never endorsed statements made by others. Rather, the College and Dr. Raimondo worked to ensure that students’ freedom of speech was protected and that the student demonstrations were safe and lawful, and they attempted to help the plaintiffs repair any harm caused by the student’s protests.”
“Our team will review the jury’s verdict and determine how to move forward,” Varner wrote.
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Texas football referee caught on tape throwing around n-word suspended
A Texas football referee has been sidelined for the 2019 season amid reports he was caught using offensive racial slurs.
Mike Atkinson was suspended by the Texas Association of Sports Officials after they heard recordings where Atkinson used the n-word, according to The Houston Chronicle.
Atkinson admits to using the racial slur.
“I thought these were private conversations between friends,” Atkinson said. “I promise you with my life, using the N-word by me is true, but I will promise you with my life, my wife’s life, my kids’ life and everything I do, (the person who taped him) also used that word.
“We were back and forth. I understand what it sounds like, but I was baited into it.”
In one of the clips, Atkinson launches into a verbal tirade about a “Chapter and Crew Mixer” hosted by the Houston Football Chapter of TASO, saying:
“I just went to the mixer the other day … a bunch of f—— n—–s wanting a free meal,” Atkinson said.
“He would find a way to n—– it up.”
“There probably was some of them … (a black official) thought he had, ’cause he wanted to be the big n—–.”
“TASO classifies the former member’s actions as unethical and unprofessional,” the statement by TASO executive director Michael Fitch read in part.
“Members who make racially insensitive remarks reflect badly on TASO and the vast majority of TASO members find those remarks repugnant. TASO has and will take disciplinary action against any member displaying any racial prejudice by words or deeds. TASO will discipline any member though they claim they made the inappropriate remarks in jest.”
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Dwaipayan Banerjee receives 2019 Levitan Prize in the Humanities
Assistant Professor Dwaipayan Banerjee of the Program in Science, Technology, and Society (STS) has been awarded the 2019 James A. (1945) and Ruth Levitan Prize in the Humanities. The prestigious award comes with a $29,500 grant that will support Banerjee's research on the history of computing in India.
Melissa Nobles, the Kenan Sahin Dean of MIT’s School of Humanities, Arts, and Social Sciences (SHASS), announced the award, noting that a committee of senior faculty had reviewed submissions for the Levitan Prize and selected Banerjee’s proposal as the most outstanding.
“Dwai’s work is extremely relevant today, and I look forward to seeing how his new project expands our understanding of technology and technological culture as a part of the human world,” Nobles says.
Postcolonial India and computing
Banerjee’s scholarship centers on the social contexts of science, technology, and medicine in the global south. He has two book projects now nearing completion: "Enduring Cancer: Health and Everyday Life in Contemporary India" (forthcoming in 2020, Duke University Press) and "Hematologies: The Political Life of Blood in India" (forthcoming in 2019, Cornell University Press; co-authored with J. Copeman). Both books assess how India’s post-colonial history has shaped, and been shaped by, practices of biomedicine and health care.
Banerjee says he was delighted to receive the Levitan Award, which is presented annually by SHASS to support innovative and creative scholarship in one of the Institute’s humanities, arts, or social science fields. “Its funds will go a long way in helping explore archives about computational research and technology spread across India, some of which have yet to receive sustained scholarly attention,” he says.
Global computing histories
Banerjee's Levitan project will investigate the post-colonial history of computing in India from the 1950s to today. “Contemporary scholarly and popular narratives about computing in India suggest that, even as India supplies cheap IT labor to the rest of the world, the country lags behind in basic computing research and development,” he says. “My new project challenges these representations.”
Banerjee adds, “In presenting this account, I urge social science research, which has predominantly focused on the history of computing in Europe and the United States, to take account of more global histories of computing.”
The project, titled "A Counter History of Computing in India," will trace major shifts in the relation between the Indian state and computing research and practice. Banerjee explains that “In the first decades after India’s independence, the postcolonial state sought to develop indigenous computing expertise and infrastructure by creating public institutions of research and education, simultaneously limiting private enterprise and the entry of global capital.”
Noting that today the vision for development relies heavily on private entrepreneurship, Banerjee asks: “Why and how did the early post-colonial vision of publicly-driven computing research and development decline?”
Policy, computing, and outsourcing
More broadly, Banerjee plans to investigate how changing policies have impacted the development of computing and shaped the global distribution of expertise and labor. “After economic liberalization in the 1980s, a transformed Indian state gave up its protectionist outlook and began to court global corporations, giving rise to the new paradigm of outsourcing."
Banerjee says he will endeavor to answer the question, “What is lost when a handful of U.S.-based corporations seek to determine hierarchies of technology work and control how its social benefits are globally distributed?” The Levitan Prize will support Banerjee's field research in India and help him develop a multi-city archive of primary sources relating to the history of computational science and technology in the region.
First awarded in 1990, the Levitan Prize in the Humanities was established through a gift from the late James A. Levitan, a 1945 MIT graduate in chemistry who was also a member of the MIT Corporation.
Story prepared by MIT SHASS Communications
Editorial and Design Director: Emily Hiestand
Writer: Kathryn O'Neill
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UPOP’s new career peer-mentoring program reaches for the STARS
MIT’s Undergraduate Practice Opportunities Program (UPOP) has striven to enhance the effectiveness of MIT students by providing professional development and career education to MIT sophomores since its inception in 2001. This past year, a new student leadership pilot program — the UPOP STARS (Student Taskforce Advancing Retention and Success) — was integrated into all aspects of the yearlong program to provide a fresh perspective and add another layer of community.
“Many of the roughly 600 UPOP graduates who are still juniors and seniors at MIT are fiercely enthusiastic and supportive of the program, so setting up a STARS team seemed like a great opportunity to provide peer education and mentoring to the current class of UPOP sophomores. The pilot year has been extremely successful, and we plan to make the STARS an ongoing component of the UPOP experience,” said Joel Schindall, acting faculty director of UPOP.
After months of planning and design involving a heavy amount of student input and best practices from nationally recognized peer career-advising programs, the UPOP STARS program was born. The inaugural class’s leaders — lovingly nicknamed PopSTARS — were seniors Ryan Koeppen, Jen McDermott, Marissa Steinmetz, Gabe Valdes, and Kim Veldee.
After an intensive training in proper career coaching methods, the STARS immediately were put to task to bring the message of professional development to MIT sophomores by helping to recruit 500-plus students to UPOP’s Class of 2021. After a successful campaign, they jumped into onboarding by assisting with orientation and résumé reviews. Over the course of three months, the STARS were able to review all of the résumés, many of which needed multiple revisions. Altogether, the STARS engaged in more than 650 in-person and email check-ins with the UPOP students.
“It was absolutely incredible to have them be a part of the team. With only five full-time UPOP staff members, it can be quite the undertaking to onboard 500 students every fall, so it was a welcome addition to have these STARS act as a force multiplier to bring an increased amount of support to all of our students,” says Justin Crim, UPOP’s student program administrator.
Résumé reviews were only the tip of the iceberg. The STARS all brought their own unique backgrounds and experiences to mentor other students.
“Over the past semester, I was very stressed about the internship process, especially the interviews. I felt overwhelmed by all of the resources at MIT and on the internet, which only increased my anxiety,” says sophomore Varsha Sridhar, a current UPOP student. “Luckily, I was able to reach out to UPOP and meet Jen, a PopSTAR. Her advice not only prepared me for technical interviews but also helped me calm down and feel more confident in myself. I am also grateful for her empathy and patience throughout our meetings, especially when I asked way too many questions. Overall, the PopSTARS program has been a very valuable resource to me at MIT. Jen’s guidance has helped me through this past semester and will probably be advice I will use in the future as well. I am glad that I was able to consult PopSTARS, because it not only provided me with a new resource, but also a basis for support into the next few years.”
With the fall semester behind them, the STARS pivoted to exploring ways to engage graduates of UPOP, as well as the greater MIT community. After exploring several opportunities, they set out on the path of paving the way for current MIT first-year students to make informed decisions about their major declarations via a new event called the First-Year Major Mixer.
“I struggled a lot with deciding on a major, and ended up not declaring until months into my sophomore year,” said Marissa Steinmetz, a Course 15 (Sloan School of Management) major. “We thought it would be fun and helpful to bring juniors and seniors together to talk to first-years about the experiences they’ve had in their majors.”
Hundreds of Insomnia Cookies were consumed as more than 80 first-year students attended the STARS’ Major Mixer in April. More than 35 UPOP-alum juniors and seniors, spanning the vast majority of majors and minors offered to undergraduates, discussed their majors and the internship opportunities they afforded. The STARS created comprehensive data sheets on all the majors, covering popular classes, average salaries, and relevant student groups, to name a few. The Major Mixer was timed to help first-years make informed decisions before the official major declaration day later that month.
The STARS program will continue next year, and hopefully beyond, to help guide the next classes of UPOP sophomores.
“The STARS have brought considerable passion, energy, and talent to their roles this year, and leave big shoes to fill for next year’s peer career advisors. It will be exciting to see the program continue to grow and innovate how we provide professional development to MIT sophomores,” says Reza Rahaman, director of UPOP.
MIT’s Undergraduate Practice Opportunities is a co-curricular program, and part of the Bernard M. Gordon-MIT Engineering Leadership Program. UPOP is open to MIT sophomores of all majors, and will be accepting applications for the class of 2022 in fall 2019. For more information visit: upop.mit.edu.
from MIT News http://bit.ly/2ZhYEn8
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Solving equations to design safer ships
David Larson ’16, SM ’18 spends much of his time thinking about boats. He has been a competitive sailor since high school. In his free time, he designs and tinkers with boats and is a member of the MIT Nautical Association Executive Committee. As a PhD student in MIT’s Laboratory for Ship and Platform Flows, he works on modeling ship-wave interactions to understand how ships behave in severe storms.
“I think I got into design and engineering through the sailing route,” says Larson. “I wanted to understand the physics of what was happening when I was out on the water.”
It was sailing that first drew Larson, who grew up near the water in San Diego, California, to MIT. On a trip as a first-year in high school, he stayed at a hotel on Memorial Drive and watched sail boats dart along the Charles River. Four years later, he enrolled at MIT.
Initially intent on studying physics, Larson quickly determined that he was most interested in mechanical engineering and ocean engineering classes. As a sophomore, he took class 2.016 (Hydrodynamics), taught by Paul Sclavounos, professor of mechanical engineering and naval architecture. The class would end up shaping the rest of his academic career.
On the second day of teaching 2.016, Sclavounos told students about his experiences designing for the America’s Cup. Larson knew some of the sailors with whom Sclavounos had worked. The two struck up a conversation after class, marking the beginning of their collaboration.
“Professor Sclavounos was the most influential in encouraging me to continue studying ocean engineering and naval architecture,” recalls Larson. Sclavounos recognized Larson’s talent and passion, often taking time after class to explain theories that Larson hadn’t yet learned.
“He was by far the best student in the class and was eagerly sought after by other students to help them through the course,” adds Sclavounos. “It was immediately evident to me that he possessed an intelligence and maturity unusual for his age.”
After graduating with his bachelor’s degree in 2016, Larson enrolled in MIT’s graduate program for mechanical engineering and ocean engineering. The summer between his undergraduate and graduate studies, he went back to his native California for an internship with Morrelli and Melvin Design and Engineering.
As an intern, Larson got to apply the concepts he learned as an undergrad — like controls, geometry optimization, and fluid mechanics — to real-world ship design. “That experience gave me a lot of practical insight into what the actual ship design process entails,” says Larson.
Back at MIT, Larson has spent his graduate studies working with Sclavounos on developing stochastic models for how ships interact with waves. While his work seems at times theoretical and abstract, it is grounded in a very practical problem: keeping ships safe in extreme weather.
“What I’m doing is motivated by practical ship design and manufacturing,” explains Larson. “I’m working to create a framework that gets more accurate predictions for how ships behave in severe storms, and to get those predictions fast enough to use in iterative design.”
Current models have come a long way in enhancing our ability to predict how waves move in the ocean. But many existing models that predict how ships move in waves, while extremely powerful, are constrained to one or two degrees of freedom, or often used over-simplified hull geometries. Larson hopes to take those models to the next level.
“The key components of our method are that we can take any realistic ship geometry directly from a CAD program, put that geometry through our model that treats the full six degrees of freedom, and get predictions for how these ships will behave in waves,” explains Larson.
Understanding how these ships behave in rough water could have immediate industrial applications. In addition to helping sailors find the safest route for their vessels, the predictions could be used to someday facilitate interactive ship design.
“My long-term goal is to eventually create an interface that can be used by design and manufacturing engineers for iterative design and optimization of the next generation of ships,” says Larson.
When Larson needs a break from mathematical equations and modeling, he uses CAD to design boats. “My research is quite mathematical, so designing boats is my outlet for reconnecting with the experimental and practical work I loved doing as an undergrad,” he adds.
Whether it’s designing boats in his spare time, competitive sailing, umpiring collegiate races across New England, helping the MIT Sailing Pavilion design its next fleet of dinghies, or developing a model to predict how ships behave in choppy seas — Larson will continue to pursue the passion for sailing he developed in childhood.
from MIT News http://bit.ly/2WXwGzU
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Forget the Bahamas. China's Cruises Are Where It's At
Experiments reveal the physics of evaporation
It’s a process so fundamental to everyday life — in everything from your morning coffeemaker to the huge power plant that provides its electricity — that it’s often taken for granted: the way a liquid boils away from a hot surface.
Yet surprisingly, this basic process has only now, for the first time, been analyzed in detail at a molecular level, in a new analysis by MIT postdoc Zhengmao Lu, professor of mechanical engineering and department head Evelyn Wang, and three others at MIT and Tokyo University. The study appears in the journal Nature Communications.
“It turns out that for the process of liquid-to-vapor phase change, a fundamental understanding of that is still relatively limited,” Wang explains. “While there’s been a lot of theories developed, there actually has not been experimental evidence of the fundamental limits of evaporation physics.”
It’s an important process to understand because it is so ubiquitous. “Evaporation is prevalent in all sorts of different types of systems such as steam generation for power plants, water desalination technologies, membrane distillation, and thermal management, like heat pipes, for example,” Wang says. Optimizing the efficiency of such processes requires a clear understanding of the dynamics at play, but in many cases engineers rely on approximations or empirical observations to guide their choices of materials and operating conditions.
By using a new technique to both control and detect temperatures at the surface of an evaporating liquid, the researchers were able to identify a set of universal characteristics involving time, pressure and temperature changes that determine the details of the evaporation process. In the process, they discovered that the key factor determining how fast the liquid could evaporate was not the temperature difference between the surface and the liquid, but rather the difference in pressure between the liquid surface and the ambient vapor.
The “rather simple question” of how a liquid evaporates at a given temperature and pressure, has remained unanswered despite many decades of study, says Pawel Keblinski, professor and head of Department of Materials Science and Engineering at Rensselaer Polytechnic Institute (RPI), who was not involved in this work. “While theorists speculated for over a century, experiment was of little help, as seeing the evaporating liquid-vapor interface and knowing the temperature and pressure near the interfaces is extremely challenging,” he says.
This new work, Keblinski says, “brings us closer to the truth.” Along with other new observational techniques developed by others, the new insights will “put us on the path to finally quantify the evaporation process after a century of efforts,” he says.
The researchers’ success was partly the result of eliminating other factors that complicate the analysis. For example, evaporation of liquid into air is strongly affected by the insulating properties of the air itself, so for these experiments the process was observed in a chamber with only the liquid and vapor present, isolated from the surrounding air. Then, in order to probe the effects right at the boundary between the liquid and the vapor, the researchers used a very thin membrane riddled with small pores to confine the water, heat it up, and measure its temperature.
That membrane, just 200 nanometers (billionths of a meter) thick, made of silicon nitride and coated with gold, carries water through its pores by capillary action, and is electrically heated to cause the water to evaporate. Then, “we also use that membrane as the sensor, to sense the temperature of the evaporating surface in an accurate and noninvasive way,” Lu says.
The gold coating of the membrane is crucial, he adds. The electrical resistance of the gold varies directly as a function of the temperature, so by carefully calibrating the system before the experiment, they are able to get a direct reading of the temperature at the exact point where evaporation is taking place, moment by moment, simply by reading the membrane’s resistance.
The data they gathered “suggests that the actual driving force or driving potential in this process is not the difference in temperature, but actually the pressure difference,” Wang says. “That's what makes everything now aligned to this really nice curve, that matches well with what theory would predict,” she says.
While it may sound simple in principle, actually developing the necessary membrane with its 100-nanometer-wide pores, which are made using a method called interference lithography, and getting the whole system to work properly took two years of hard work, she says.
Overall, the findings so far “are consistent with what theory predicts,” Lu says, but it is still important to have that confirmation. “While theories have predicted things, there’s been no experimental evidence that the theories are correct,” Wang adds.
The new findings also provide guidance for engineers designing new evaporation-based systems, providing information on both the selection of the best working fluids for a given situation, as well as the conditions of pressure and removal of ambient air from the system. “Using this system as a guideline you can sort of optimize the working conditions for certain kinds of applications,” Lu says.
This team “did a series of elegant experiments designed to confirm theoretical predictions,” says Joel Plawsky, professor of chemical and biological engineering at
RPI, who was not involved in this work. “The apparatus was unique and painstakingly difficult to fabricate and operate. The data was exceptional in its quality and detail. Any time one can collapse a large spread of data by developing a dimensionless formulation,” that is, one that applies equally well under a wide variety of conditions, “that represents a major advance for engineering,” he says.
Plawsly adds, “There are many questions that this work opens up about the behavior of different fluids and of fluid mixtures. One can imagine many years’ worth of follow-on work.”
The team also included Ikuya Kinefuchi at the University of Tokyo and graduate students Kyle Wilke and Geoffrey Vaartstra at MIT. The work was supported by the Air Force Office of Scientific Research and the National Science Foundation.
from MIT News http://bit.ly/2X2H892
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How reality TV show helped ID former University of Florida football player as wife’s killer in cold case
A former University of Florida captain is now facing murder charges
—Univ. of Florida apologizes for White staffer ‘aggressively’ pushing Black grads off stage—
Earl Antonio “Tony” Joiner was arrested Saturday on a charge of second-degree murder in the death of wife Heyzel Obando, the Fort Myers Police Department said in a statement.
The body of Joiner’s 26-year-old wife was discovered in an apartment on Feb. 14, 2016.
Police worked in tandem with the Oxygen TV series “Cold Justice” and the Office of the State Attorney to hone in on Joiner and make the arrest, according to CNN affiliate WFTX.
Obando was killed in Feb 2016 and his body was found in an apartment, according to police.
On Friday, “Cold Justice” finished production ion the Obando case.
“It’s a really tragic case to read,” Kelly Siegler, a former prosecutor who also hosts “Cold Justice,” told WFTX.
“When you read it, it’s just one of those cases where you think, ‘with just a little bit more effort and concentration and push, it can be cleared.'”
—Aaron Hernandez’s fiancée Announces $20MIL lawsuit against Patriots and NFL––
Joiner reported finding Obando shot to death on Valentine’s Day three years ago.
The post How reality TV show helped ID former University of Florida football player as wife’s killer in cold case appeared first on theGrio.
from theGrio https://on.thegrio.com/2wMewlS
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Post-Apocalyptic Survival Skills: How to Measure Acceleration
Author sues book publisher who dropped her after she shamed Black MTA worker for eating on train
Natasha Tynes, the woman who lost her book deal after snitching on a Black transit worker who was catching a bite to eat on a train in a tweet that went viral, is now suing her publisher and blaming them for her downfall.
—Author shames Black DC Metro employee for eating on train, book launch postponed—
Rare Bird Lit decided to distance itself from the author after she shamed a Black woman for eating on her way to work.
“When you’re on your morning commute & see @wmata employee in UNIFORM eating on the train I thought we were not allowed to eat on the train. This is unacceptable. Hope @wmata responds.”
The social media backlash agains the writer was swift and soon her publisher was feeling the heat and decided to drop the author.
Tynes “did something truly horrible today in tweeting a picture of a metro worker eating her breakfast on the train this morning and drawing attention to her employer,” Rare Birds said in a statement. “Black women face a constant barrage of this kind of inappropriate behavior directed toward them and a constant policing of their bodies.”
Tynes has now filed a $13.4 million-dollar lawsuit against Rare Bird Lit blaming the publisher for breach of contract and defamation, USA Today reports.
Tynes, a Jordanian-American writer, reportedly claims in the suit that she has been forced to leave the country amid death threats and online harassment and racial slurs.
Tynes said she has endured “extreme emotional distress” and had to be hospitalized for chest pains, severe anxiety and suicidal thoughts, according to the lawsuit.
The author said Rare Bird is an ‘an all-white company,’ that is benefitting from characterizing her as a racist “immigrant woman of color.”
Rare Bird’s attorney David S. Eisen told USA Today said that Tynes caused these issues on her own.
“It is ironic that, having taken advantage of her First Amendment rights with an ill-advised tweet, Ms. Tynes now seeks to stifle and punish use of those very same rights of a respected book publisher who legitimately expressed its opinions of her conduct, rather than take responsibility for her own actions,” Eisien said.
The post Author sues book publisher who dropped her after she shamed Black MTA worker for eating on train appeared first on theGrio.
from theGrio https://on.thegrio.com/2I6GyPr
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Attack on Mali village 'kills 100'
Instant Pot Ace Multi-Use Cooking & Beverage Blender Review: Excellent, But Only With the Right Cookbook
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