ow Everything I Know In One Place By feedproxy.google.com Published On :: Wed, 17 Jul 2019 13:15:58 +0000 It was surreal to sit down at the mic and record this show after spending the last few years (5 a.m. mornings, late, late nights, and many long weekends hunkered down) writing a book that I’m proud and beyond excited to share with YOU and the world. It’s called CREATIVE CALLING and it’s officially available for pre-order TODAY! In this episode, you get the little sneak peek at the book (yes, I read a little from it) and a little background on why I needed to write it. After all, life isn’t about “finding” fulfillment and success – it’s about creating it. Creativity is a force inside every person that, when unleashed, transforms our lives and delivers vitality to everything we do. Establishing a creative practice is therefore our most valuable and urgent task – as important to our well-being as exercise or nutrition. The good news? Creativity isn’t a skill—it’s a habit available to everyone: beginners and lifelong creators, entrepreneurs to executives, astronauts to zookeepers, and everyone in between. It’s only through small, daily actions that we can supercharge our innate creativity and (re-)discover our personal power in life. Everything you need is inside you right now. Whether your ambition is a creative career, completing a creative […] The post Everything I Know In One Place appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Inspiration Podcast
ow Jump into Fear with Jeremy Cowart By feedproxy.google.com Published On :: Wed, 21 Aug 2019 13:00:45 +0000 Jeremy Cowart was named the “Most Influential Photographers on the Internet” by Huffington Post in 2014. He’s the founder of a global photography movement, Help-Portrait, to give back to those in need. As well as many photography projects bridging empathy and creativity into awareness and action. If you’ve been a long time listener / watcher of this show, you’ll recognize Jeremy from one of the first episodes nearly 10 years ago. Jeremy’s vision and ambition have not slowed down. Today on the show, we get into his new book I’m Possible and his biggest project to date, building a hotel where every aspect serves someone in need. We get into facing fears, overcoming doubt, and how to turn the seemingly impossible to possible. In this episode: The fear of having a dream that’s so big. Chasing a dream for a decade or lifetime. How do you take action and get paralyzed because it’s so big? How to chase curiosity despite your fear of starting something new? Whether you’re just starting out or you’re thinking about transitioning from something you love doing and are already good at…. Battling against our inner monologue pulling us away from the thing we know we […] The post Jump into Fear with Jeremy Cowart appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Podcast creativity interview jeremy cowart Photographer The Purpose Hotel
ow How to Build Your Brand /w Ben Von Wong By feedproxy.google.com Published On :: Wed, 09 Oct 2019 13:15:07 +0000 Back in 2012, budding photographer Ben Von Wong stopped by my photo studio in Seattle to say hello. Fast forward to present day and he’s making headlines working with some of the world’s largest brands like Nike and IBM, create work that combines art & activism. His work has been featured numerous times on Buzzfeed, Gizmodo, Mashable and the Huffington Post to name a few. So when he stopped by the CreativeLive studios not too long ago, I wanted to pick his brain one of the most common questions I get on how to stand out and build a personal brand. In this episode: Put work in your portfolio you want to be hired to do. If you shoot weddings and also muscle cars, consider separate sites. One of Ben’s main considerations for helping his project spread? Create with the headline in mind. Ben shares a little about his process to discover his unique style and thumbprint to his work. Enjoy! FOLLOW BEN: instagram | twitter | website Listen to the Podcast Subscribe Watch the Episode This podcast is brought to you by CreativeLive. CreativeLive is the world’s largest hub for online creative education in photo/video, art/design, music/audio, […] The post How to Build Your Brand /w Ben Von Wong appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE cjRAW People Podcast Ben Von Wong brand personal style photography
ow How To Get UN-STUCK From Anything in Life That’s Got You Down [with Lewis Howes] By feedproxy.google.com Published On :: Wed, 23 Oct 2019 13:26:05 +0000 Ever felt STUCK with something in your life? Blocked, like you can’t get past this mental state, this hurdle, this creative block, this bad habit, this… Wait a minute. Why am I even asking that question? Of course you’ve been stuck before. We’ve literally ALL been stuck before. And by extension we all know how much it sucks to be in this state of mind. AND – on the flipside – how amazing it is when you can reclaim your life and get back to the things you want to be thinking, doing, and becoming. I’m obsessed with overcoming the mental blockers that try to keep me down – and I think it’s been a big piece of my personal success. Which is why I thought this little nugget might help. ENTER: Lewis Howes. My good friend Lewis Howes was in the studio shooting his newest CreativeLive course last week and I was able to snag him for a few minutes to chat about his new book and his amazingly simple, yet powerful process for reclaiming our lives and live our biggest dreams. In this episode, Lewis shares a powerful experience from his life and how- on reflection – it helped […] The post How To Get UN-STUCK From Anything in Life That’s Got You Down [with Lewis Howes] appeared first on Chase Jarvis Photography. Full Article Business cjRAW How To Inspiration People Pop Culture Videos "chase jarvis" book chase creativeLIVE Dream goals habits Lewis Howes life lifestyle podcast productivity School of Greatness success video visualization
ow How to Find Yourself with Glennon Doyle By feedproxy.google.com Published On :: Wed, 22 Apr 2020 12:10:36 +0000 Very excited to have my friend, truth-teller, and Bestselling Author, Glennon Doyle back on the show. Her newly released book, UNTAMED, is a powerful memoir and wake-up call about being forged in the fire of anger, heartbreak, and discontent to finally finding yourself. In this episode, we’re coming to you LIVE from our living rooms to chat about how to listen to the inner voice and take control of your life. If you’re not familiar with Glennon’s work, she is the bestselling author of many books including LOVE WARRIOR, which was selected as an Oprah’s Book Club pick, as well as the New York Times bestseller CARRY ON, WARRIOR. An activist and thought leader, Glennon was named among SuperSoul100’s inaugural group of “awakened leaders who are using their voices and talent to elevate humanity.” She is the founder and president of Together Rising, an all-women led nonprofit organization that has revolutionized grassroots philanthropy – raising over $20 Million for women, families and children in crisis. She lives in Florida with her wife and three children. Enjoy! FOLLOW GLENNON: instagram | twitter | website Listen to the Podcast Subscribe Watch the Episode This podcast is brought to you by CreativeLive. CreativeLive […] The post How to Find Yourself with Glennon Doyle appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Podcast fear personal development relationships self confidence self-care trust
ow Make It Til You Make It with Owen Smith By feedproxy.google.com Published On :: Wed, 29 Apr 2020 13:00:36 +0000 If you happened to come across a Youtube video I put out not too long ago featuring Owen Smith, you’ll know the backstory how we connected for this episode of the Chase Jarvis LIVE show. Of course, we hoped to meet in person, but for now we’re coming LIVE to you from our living rooms. Owen Smith is a comedian, actor, writer, and the creator of a new YouTube show: Notebooks. He has performed stand-up on Conan, Colbert and is a regular at the Comedy Store Hollywood and Comedy Cellar in New York. He’s written for shows such as ABC’s Black•ish, Survivor’s Remorse (Starz), The Arsenio Hall Show, The ESPY’s (on ESPN with Drake and ABC with Joel McHale), The Guy’s Choice Awards, Whitney(NBC), Deon Cole’s Black Box (TBS), Are We There Yet (TBS), and Everybody Hates Chris. In this episode, we explore Owen’s Notebook project (so good!) and go deep into growing and developing as an artist, putting work into the world, learning to trust your instincts, finding the right time/place for your ideas, and so much more. Definitely check out his new show Notebooks. So relatable and funny for any creator. Enjoy! FOLLOW OWEN: instagram | twitter | […] The post Make It Til You Make It with Owen Smith appeared first on Chase Jarvis Photography. Full Article chasejarvisLIVE Podcast actor art business comedian creativity producer standup comedy writer
ow How to Foster Real-Time Client Engagement During Moderated Research By feedproxy.google.com Published On :: Mon, 17 Feb 2020 08:00:00 -0500 When we conduct moderated research, like user interviews or usability tests, for our clients, we encourage them to observe as many sessions as possible. We find when clients see us interview their users, and get real-time responses, they’re able to learn about the needs of their users in real-time and be more active participants in the process. One way we help clients feel engaged with the process during remote sessions is to establish a real-time communication backchannel that empowers clients to flag responses they’d like to dig into further and to share their ideas for follow-up questions. There are several benefits to establishing a communication backchannel for moderated sessions:Everyone on the team, including both internal and client team members, can be actively involved throughout the data collection process rather than waiting to passively consume findings.Team members can identify follow-up questions in real-time which allows the moderator to incorporate those questions during the current session, rather than just considering them for future sessions.Subject matter experts can identify more detailed and specific follow-up questions that the moderator may not think to ask.Even though the whole team is engaged, a single moderator still maintains control over the conversation which creates a consistent experience for the participant.If you’re interested in creating your own backchannel, here are some tips to make the process work smoothly:Use the chat tool that is already being used on the project. In most cases, we use a joint Slack workspace for the session backchannel but we’ve also used Microsoft Teams.Create a dedicated channel like #moderated-sessions. Conversation in this channel should be limited to backchannel discussions during sessions. This keeps the communication consolidated and makes it easier for the moderator to stay focused during the session.Keep communication limited. Channel participants should ask basic questions that are easy to consume quickly. Supplemental commentary and analysis should not take place in the dedicated channel.Use emoji responses. The moderator can add a quick thumbs up to indicate that they’ve seen a question.Introducing backchannels for communication during remote moderated sessions has been a beneficial change to our research process. It not only provides an easy way for clients to stay engaged during the data collection process but also increases the moderator’s ability to focus on the most important topics and to ask the most useful follow-up questions. Full Article Process Research
ow Markdown Comes Alive! Part 1, Basic Editor By feedproxy.google.com Published On :: Wed, 26 Feb 2020 08:00:00 -0500 In my last post, I covered what LiveView is at a high level. In this series, we’re going to dive deeper and implement a LiveView powered Markdown editor called Frampton. This series assumes you have some familiarity with Phoenix and Elixir, including having them set up locally. Check out Elizabeth’s three-part series on getting started with Phoenix for a refresher. This series has a companion repository published on GitHub. Get started by cloning it down and switching to the starter branch. You can see the completed application on master. Our goal today is to make a Markdown editor, which allows a user to enter Markdown text on a page and see it rendered as HTML next to it in real-time. We’ll make use of LiveView for the interaction and the Earmark package for rendering Markdown. The starter branch provides some styles and installs LiveView. Rendering Markdown Let’s set aside the LiveView portion and start with our data structures and the functions that operate on them. To begin, a Post will have a body, which holds the rendered HTML string, and title. A string of markdown can be turned into HTML by calling Post.render(post, markdown). I think that just about covers it! First, let’s define our struct in lib/frampton/post.ex: defmodule Frampton.Post do defstruct body: "", title: "" def render(%__MODULE{} = post, markdown) do # Fill me in! end end Now the failing test (in test/frampton/post_test.exs): describe "render/2" do test "returns our post with the body set" do markdown = "# Hello world!" assert Post.render(%Post{}, markdown) == {:ok, %Post{body: "<h1>Hello World</h1> "}} end end Our render method will just be a wrapper around Earmark.as_html!/2 that puts the result into the body of the post. Add {:earmark, "~> 1.4.3"} to your deps in mix.exs, run mix deps.get and fill out render function: def render(%__MODULE{} = post, markdown) do html = Earmark.as_html!(markdown) {:ok, Map.put(post, :body, html)} end Our test should now pass, and we can render posts! [Note: we’re using the as_html! method, which prints error messages instead of passing them back to the user. A smarter version of this would handle any errors and show them to the user. I leave that as an exercise for the reader…] Time to play around with this in an IEx prompt (run iex -S mix in your terminal): iex(1)> alias Frampton.Post Frampton.Post iex(2)> post = %Post{} %Frampton.Post{body: "", title: ""} iex(3)> {:ok, updated_post} = Post.render(post, "# Hello world!") {:ok, %Frampton.Post{body: "<h1>Hello world!</h1> ", title: ""}} iex(4)> updated_post %Frampton.Post{body: "<h1>Hello world!</h1> ", title: ""} Great! That’s exactly what we’d expect. You can find the final code for this in the render_post branch. LiveView Editor Now for the fun part: Editing this live! First, we’ll need a route for the editor to live at: /editor sounds good to me. LiveViews can be rendered from a controller, or directly in the router. We don’t have any initial state, so let's go straight from a router. First, let's put up a minimal test. In test/frampton_web/live/editor_live_test.exs: defmodule FramptonWeb.EditorLiveTest do use FramptonWeb.ConnCase import Phoenix.LiveViewTest test "the editor renders" do conn = get(build_conn(), "/editor") assert html_response(conn, 200) =~ "data-test="editor"" end end This test doesn’t do much yet, but notice that it isn’t live view specific. Our first render is just the same as any other controller test we’d write. The page’s content is there right from the beginning, without the need to parse JavaScript or make API calls back to the server. Nice. To make that test pass, add a route to lib/frampton_web/router.ex. First, we import the LiveView code, then we render our Editor: import Phoenix.LiveView.Router # … Code skipped ... # Inside of `scope "/"`: live "/editor", EditorLive Now place a minimal EditorLive module, in lib/frampton_web/live/editor_live.ex: defmodule FramptonWeb.EditorLive do use Phoenix.LiveView def render(assigns) do ~L""" <div data-test=”editor”> <h1>Hello world!</h1> </div> """ end def mount(_params, _session, socket) do {:ok, socket} end end And we have a passing test suite! The ~L sigil designates that LiveView should track changes to the content inside. We could keep all of our markup in this render/1 method, but let’s break it out into its own template for demonstration purposes. Move the contents of render into lib/frampton_web/templates/editor/show.html.leex, and replace EditorLive.render/1 with this one liner: def render(assigns), do: FramptonWeb.EditorView.render("show.html", assigns). And finally, make an EditorView module in lib/frampton_web/views/editor_view.ex: defmodule FramptonWeb.EditorView do use FramptonWeb, :view import Phoenix.LiveView end Our test should now be passing, and we’ve got a nicely separated out template, view and “live” server. We can keep markup in the template, helper functions in the view, and reactive code on the server. Now let’s move forward to actually render some posts! Handling User Input We’ve got four tasks to accomplish before we are done: Take markdown input from the textarea Send that input to the LiveServer Turn that raw markdown into HTML Return the rendered HTML to the page. Event binding To start with, we need to annotate our textarea with an event binding. This tells the liveview.js framework to forward DOM events to the server, using our liveview channel. Open up lib/frampton_web/templates/editor/show.html.leex and annotate our textarea: <textarea phx-keyup="render_post"></textarea> This names the event (render_post) and sends it on each keyup. Let’s crack open our web inspector and look at the web socket traffic. Using Chrome, open the developer tools, navigate to the network tab and click WS. In development you’ll see two socket connections: one is Phoenix LiveReload, which polls your filesystem and reloads pages appropriately. The second one is our LiveView connection. If you let it sit for a while, you’ll see that it's emitting a “heartbeat” call. If your server is running, you’ll see that it responds with an “ok” message. This lets LiveView clients know when they've lost connection to the server and respond appropriately. Now, type some text and watch as it sends down each keystroke. However, you’ll also notice that the server responds with a “phx_error” message and wipes out our entered text. That's because our server doesn’t know how to handle the event yet and is throwing an error. Let's fix that next. Event handling We’ll catch the event in our EditorLive module. The LiveView behavior defines a handle_event/3 callback that we need to implement. Open up lib/frampton_web/live/editor_live.ex and key in a basic implementation that lets us catch events: def handle_event("render_post", params, socket) do IO.inspect(params) {:noreply, socket} end The first argument is the name we gave to our event in the template, the second is the data from that event, and finally the socket we’re currently talking through. Give it a try, typing in a few characters. Look at your running server and you should see a stream of events that look something like this: There’s our keystrokes! Next, let’s pull out that value and use it to render HTML. Rendering Markdown Lets adjust our handle_event to pattern match out the value of the textarea: def handle_event("render_post", %{"value" => raw}, socket) do Now that we’ve got the raw markdown string, turning it into HTML is easy thanks to the work we did earlier in our Post module. Fill out the body of the function like this: {:ok, post} = Post.render(%Post{}, raw) IO.inspect(post) If you type into the textarea you should see output that looks something like this: Perfect! Lastly, it’s time to send that rendered html back to the page. Returning HTML to the page In a LiveView template, we can identify bits of dynamic data that will change over time. When they change, LiveView will compare what has changed and send over a diff. In our case, the dynamic content is the post body. Open up show.html.leex again and modify it like so: <div class="rendered-output"> <%= @post.body %> </div> Refresh the page and see: Whoops! The @post variable will only be available after we put it into the socket’s assigns. Let’s initialize it with a blank post. Open editor_live.ex and modify our mount/3 function: def mount(_params, _session, socket) do post = %Post{} {:ok, assign(socket, post: post)} end In the future, we could retrieve this from some kind of storage, but for now, let's just create a new one each time the page refreshes. Finally, we need to update the Post struct with user input. Update our event handler like this: def handle_event("render_post", %{"value" => raw}, %{assigns: %{post: post}} = socket) do {:ok, post} = Post.render(post, raw) {:noreply, assign(socket, post: post) end Let's load up http://localhost:4000/editor and see it in action. Nope, that's not quite right! Phoenix won’t render this as HTML because it’s unsafe user input. We can get around this (very good and useful) security feature by wrapping our content in a raw/1 call. We don’t have a database and user processes are isolated from each other by Elixir. The worst thing a malicious user could do would be crash their own session, which doesn’t bother me one bit. Check the edit_posts branch for the final version. Conclusion That’s a good place to stop for today. We’ve accomplished a lot! We’ve got a dynamically rendering editor that takes user input, processes it and updates the page. And we haven’t written any JavaScript, which means we don’t have to maintain or update any JavaScript. Our server code is built on the rock-solid foundation of the BEAM virtual machine, giving us a great deal of confidence in its reliability and resilience. In the next post, we’ll tackle making a shared editor, allowing multiple users to edit the same post. This project will highlight Elixir’s concurrency capabilities and demonstrate how LiveView builds on them to enable some incredible user experiences. Full Article Code Back-end Engineering
ow A Viget Exploration: How Tech Can Help in a Pandemic By feedproxy.google.com Published On :: Wed, 25 Mar 2020 16:49:00 -0400 Viget Explorations have always been the result of our shared curiosities. They’re usually a spontaneous outcome of team downtime and a shared problem we’ve experienced. We use our Explorations to pursue our diverse interests and contribute to the conversations about building a better digital world. As the COVID-19 crisis emerged, we were certainly experiencing a shared problem. As a way to keep busy and manage our anxieties, a small team came together to dive into how technology has helped, and, unfortunately, hindered the community response to the current pandemic. Privia Medical Group Telehealth Native Apps We started by researching the challenges we saw: information overload, a lack of clarity, individual responsibility, and change. Then we brainstormed possible technical solutions that could further improve how communities respond to a pandemic. Click here to see our Exploration on some possible ways to take the panic out of pandemics. While we aren’t currently pursuing the solutions outlined in the Exploration, we’d love to hear what you think about these approaches, as well as any ideas you have for how technology can help address the outlined challenges. Please note, this Exploration doesn’t provide medical information. Visit the Center for Disease Control’s website for current information and COVID-19, its symptoms, and treatments. At Viget, we’re adjusting to this crisis for the safety of our clients, our staff, and our communities. If you’d like to hear from Viget's co-founder, Brian Williams, you can read his article on our response to the situation. Full Article News & Culture
ow How To Succeed In Wireframe Design By feedproxy.google.com Published On :: Wed, 29 Apr 2020 12:30:00 +0000 For the most part, we tend to underestimate things that are familiar to us. It is also very likely that we will underestimate those things that though new, seem very simple to process. And that is correct to some degree. But, when we are faced with complex cases and all measures are taken, a good and solid understanding of the basics could help us to find the right solutions. In this article, we will take a deeper look at one of the most simple, thus, quite often underrated activities in web development that is the design of wireframes. Full Article
ow Smashing Podcast Episode 15 With Phil Smith: How Can I Build An App In 10 Days? By feedproxy.google.com Published On :: Tue, 05 May 2020 05:00:00 +0000 In this episode of the Smashing Podcast, we’re talking about building apps on a tight timeline. How can you quickly turn around a project to respond to an emerging situation like COVID-19? Drew McLellan talks to Phil Smith to find out. Show Notes CardMedic React Native React Native for Web Expo Apiary Phil’s company amillionmonkeys Phil’s personal blog and Twitter Weekly Update Getting Started With Nuxt Implementing Dark Mode In React Apps Using styled-components How To Succeed In Wireframe Design Mirage JS Deep Dive: Understanding Mirage JS Models And Associations (Part 1) Readability Algorithms Should Be Tools, Not Targets Transcript Drew McLellan: He is director of the full-stack web development studio amillionmonkeys, where he partners with business owners and creative agencies to build digital products that make an impact. Full Article
ow How To Build A Vue Survey App Using Firebase Authentication And Database By feedproxy.google.com Published On :: Fri, 08 May 2020 11:00:00 +0000 In this tutorial, you’ll be building a Survey App, where we’ll learn to validate our users form data, implement Authentication in Vue, and be able to receive survey data using Vue and Firebase (a BaaS platform). As we build this app, we’ll be learning how to handle form validation for different kinds of data, including reaching out to the backend to check if an email is already taken, even before the user submits the form during sign up. Full Article
ow Google Lens now copies handwritten text and pastes it straight to your computer By feedproxy.google.com Published On :: Thu, 07 May 2020 19:59:08 +0000 Are there still folks among you who, like me, prefer handwriting to typing? If you’re in this group, you’ll love this new feature on Google Lens. The app now lets you scan your handwritten notes, copy them, and paste them straight to your computer. I gave it a spin, and I bring you my impressions […] The post Google Lens now copies handwritten text and pastes it straight to your computer appeared first on DIY Photography. Full Article news AI Artificial Intelligence Google AI Google Lens hadwriting handwritten
ow #COVIDwear: a hilarious photo series showing quarantine fashion of remote workers By feedproxy.google.com Published On :: Fri, 08 May 2020 12:04:34 +0000 With the coronavirus pandemic, many folks switched to working online. Things like teaching, business meetings and other face-to-face activities have been replaced with video calls. Home has become both home and workplace, and admit it: your wardrobe totally reflects this. Creative duo The Workmans shows this “fashion crossover” in their latest photo series #COVIDwear. The […] The post #COVIDwear: a hilarious photo series showing quarantine fashion of remote workers appeared first on DIY Photography. Full Article Inspiration Alex Workman Chelsea Workman Coronavirus COVID-19 funny portraits quarantine self-isolation The Workmans
ow Watch YouTube’s most informed sock puppet teach you how to shoot with manual exposure By feedproxy.google.com Published On :: Fri, 08 May 2020 17:29:41 +0000 For those who’ve never seen TheCrafsMan SteadyCraftin on YouTube, you’re in for a treat – even if you already understand everything contained within this 25-minute video. For those who have, you know exactly what to expect. I’ve been following this rather unconventional channel for a while now. It covers a lot of handy DIY and […] The post Watch YouTube’s most informed sock puppet teach you how to shoot with manual exposure appeared first on DIY Photography. Full Article Tutorials exposure Exposure Triangle photography basics SteadyCraftin TheCraftsMan
ow Review: Alberto Cairo, How Charts Lie By eagereyes.org Published On :: Tue, 12 Nov 2019 05:07:05 +0000 Alberto Cairo’s new book, How Charts Lie, takes readers on a tour of how charts are used and misused, and teaches them how to not be misled. It’s a useful book for both makers and consumers of charts, in the news, business, and pretty much anywhere else. When Alberto started talking about the title on […] Full Article Blog 2019 Book Reviews
ow On boundedness, gradient estimate, blow-up and convergence in a two-species and two-stimuli chemotaxis system with/without loop. (arXiv:1909.04587v4 [math.AP] UPDATED) By arxiv.org Published On :: In this work, we study dynamic properties of classical solutions to a homogenous Neumann initial-boundary value problem (IBVP) for a two-species and two-stimuli chemotaxis model with/without chemical signalling loop in a 2D bounded and smooth domain. We successfully detect the product of two species masses as a feature to determine boundedness, gradient estimates, blow-up and $W^{j,infty}(1leq jleq 3)$-exponential convergence of classical solutions for the corresponding IBVP. More specifically, we first show generally a smallness on the product of both species masses, thus allowing one species mass to be suitably large, is sufficient to guarantee global boundedness, higher order gradient estimates and $W^{j,infty}$-convergence with rates of convergence to constant equilibria; and then, in a special case, we detect a straight line of masses on which blow-up occurs for large product of masses. Our findings provide new understandings about the underlying model, and thus, improve and extend greatly the existing knowledge relevant to this model. Full Article
ow Exotic Springer fibers for orbits corresponding to one-row bipartitions. (arXiv:1810.03731v2 [math.RT] UPDATED) By arxiv.org Published On :: We study the geometry and topology of exotic Springer fibers for orbits corresponding to one-row bipartitions from an explicit, combinatorial point of view. This includes a detailed analysis of the structure of the irreducible components and their intersections as well as the construction of an explicit affine paving. Moreover, we compute the ring structure of cohomology by constructing a CW-complex homotopy equivalent to the exotic Springer fiber. This homotopy equivalent space admits an action of the type C Weyl group inducing Kato's original exotic Springer representation on cohomology. Our results are described in terms of the diagrammatics of the one-boundary Temperley-Lieb algebra (also known as the blob algebra). This provides a first step in generalizing the geometric versions of Khovanov's arc algebra to the exotic setting. Full Article
ow The 2d-directed spanning forest converges to the Brownian web. (arXiv:1805.09399v3 [math.PR] UPDATED) By arxiv.org Published On :: The two-dimensional directed spanning forest (DSF) introduced by Baccelli and Bordenave is a planar directed forest whose vertex set is given by a homogeneous Poisson point process $mathcal{N}$ on $mathbb{R}^2$. If the DSF has direction $-e_y$, the ancestor $h(u)$ of a vertex $u in mathcal{N}$ is the nearest Poisson point (in the $L_2$ distance) having strictly larger $y$-coordinate. This construction induces complex geometrical dependencies. In this paper we show that the collection of DSF paths, properly scaled, converges in distribution to the Brownian web (BW). This verifies a conjecture made by Baccelli and Bordenave in 2007. Full Article
ow Simulation of Integro-Differential Equation and Application in Estimation of Ruin Probability with Mixed Fractional Brownian Motion. (arXiv:1709.03418v6 [math.PR] UPDATED) By arxiv.org Published On :: In this paper, we are concerned with the numerical solution of one type integro-differential equation by a probability method based on the fundamental martingale of mixed Gaussian processes. As an application, we will try to simulate the estimation of ruin probability with an unknown parameter driven not by the classical L'evy process but by the mixed fractional Brownian motion. Full Article
ow Local mollification of Riemannian metrics using Ricci flow, and Ricci limit spaces. (arXiv:1706.09490v2 [math.DG] UPDATED) By arxiv.org Published On :: We use Ricci flow to obtain a local bi-Holder correspondence between Ricci limit spaces in three dimensions and smooth manifolds. This is more than a complete resolution of the three-dimensional case of the conjecture of Anderson-Cheeger-Colding-Tian, describing how Ricci limit spaces in three dimensions must be homeomorphic to manifolds, and we obtain this in the most general, locally non-collapsed case. The proofs build on results and ideas from recent papers of Hochard and the current authors. Full Article
ow The classification of Rokhlin flows on C*-algebras. (arXiv:1706.09276v6 [math.OA] UPDATED) By arxiv.org Published On :: We study flows on C*-algebras with the Rokhlin property. We show that every Kirchberg algebra carries a unique Rokhlin flow up to cocycle conjugacy, which confirms a long-standing conjecture of Kishimoto. We moreover present a classification theory for Rokhlin flows on C*-algebras satisfying certain technical properties, which hold for many C*-algebras covered by the Elliott program. As a consequence, we obtain the following further classification theorems for Rokhlin flows. Firstly, we extend the statement of Kishimoto's conjecture to the non-simple case: Up to cocycle conjugacy, a Rokhlin flow on a separable, nuclear, strongly purely infinite C*-algebra is uniquely determined by its induced action on the prime ideal space. Secondly, we give a complete classification of Rokhlin flows on simple classifiable $KK$-contractible C*-algebras: Two Rokhlin flows on such a C*-algebra are cocycle conjugate if and only if their induced actions on the cone of lower-semicontinuous traces are affinely conjugate. Full Article
ow A reaction-diffusion system to better comprehend the unlockdown: Application of SEIR-type model with diffusion to the spatial spread of COVID-19 in France. (arXiv:2005.03499v1 [q-bio.PE]) By arxiv.org Published On :: A reaction-diffusion model was developed describing the spread of the COVID-19 virus considering the mean daily movement of susceptible, exposed and asymptomatic individuals. The model was calibrated using data on the confirmed infection and death from France as well as their initial spatial distribution. First, the system of partial differential equations is studied, then the basic reproduction number, R0 is derived. Second, numerical simulations, based on a combination of level-set and finite differences, shown the spatial spread of COVID-19 from March 16 to June 16. Finally, scenarios of unlockdown are compared according to variation of distancing, or partially spatial lockdown. Full Article
ow On completion of unimodular rows over polynomial extension of finitely generated rings over $mathbb{Z}$. (arXiv:2005.03485v1 [math.AC]) By arxiv.org Published On :: In this article, we prove that if $R$ is a finitely generated ring over $mathbb{Z}$ of dimension $d, dgeq2, frac{1}{d!}in R$, then any unimodular row over $R[X]$ of length $d+1$ can be mapped to a factorial row by elementary transformations. Full Article
ow Sums of powers of integers and hyperharmonic numbers. (arXiv:2005.03407v1 [math.NT]) By arxiv.org Published On :: In this paper, we derive a formula for the sums of powers of the first $n$ positive integers that involves the hyperharmonic numbers and the Stirling numbers of the second kind. Then, using an explicit representation for the hyperharmonic numbers, we generalize this formula to the sums of powers of an arbitrary arithmetic progression. Moreover, as a by-product, we express the Bernoulli polynomials in terms of the hyperharmonic polynomials and the Stirling numbers of the second kind. Full Article
ow A remark on the Laplacian flow and the modified Laplacian co-flow in G2-Geometry. (arXiv:2005.03332v1 [math.DG]) By arxiv.org Published On :: We observe that the DeTurck Laplacian flow of G2-structures introduced by Bryant and Xu as a gauge fixing of the Laplacian flow can be regarded as a flow of G2-structures (not necessarily closed) which fits in the general framework introduced by Hamilton in [4]. Full Article
ow Some local Maximum principles along Ricci Flow. (arXiv:2005.03189v1 [math.DG]) By arxiv.org Published On :: In this note, we establish a local maximum principle along Ricci flow under scaling invariant curvature condition. This unifies the known preservation of nonnegativity results along Ricci flow with unbounded curvature. By combining with the Dirichlet heat kernel estimates, we also give a more direct proof of Hochard's localized version of a maximum principle given by R. Bamler, E. Cabezas-Rivas, and B. Wilking on the lower bound of curvature conditions. Full Article
ow On planar graphs of uniform polynomial growth. (arXiv:2005.03139v1 [math.PR]) By arxiv.org Published On :: Consider an infinite planar graph with uniform polynomial growth of degree d > 2. Many examples of such graphs exhibit similar geometric and spectral properties, and it has been conjectured that this is necessary. We present a family of counterexamples. In particular, we show that for every rational d > 2, there is a planar graph with uniform polynomial growth of degree d on which the random walk is transient, disproving a conjecture of Benjamini (2011). By a well-known theorem of Benjamini and Schramm, such a graph cannot be a unimodular random graph. We also give examples of unimodular random planar graphs of uniform polynomial growth with unexpected properties. For instance, graphs of (almost sure) uniform polynomial growth of every rational degree d > 2 for which the speed exponent of the walk is larger than 1/d, and in which the complements of all balls are connected. This resolves negatively two questions of Benjamini and Papasoglou (2011). Full Article
ow On the Brown-Peterson cohomology of $BPU_n$ in lower dimensions and the Thom map. (arXiv:2005.03107v1 [math.AT]) By arxiv.org Published On :: For an odd prime $p$, we determined the Brown-Peterson cohomology of $BPU_n$ in dimensions $-(2p-2)leq ileq 2p+2$, where $BPU_n$ is the classifying space of the projective unitary group $PU_n$. We construct a family of $p$-torsion classes $eta_{p,k}in BP^{2p^{k+1}+2}(BPU_n)$ for $p|n$ and $kgeq 0$ and identify their images under the Thom map with well understood cohomology classes in $H^*(BPU_n;mathbb{Z}_{(p)})$. Full Article
ow A Quantum Algorithm To Locate Unknown Hashes For Known N-Grams Within A Large Malware Corpus. (arXiv:2005.02911v2 [quant-ph] UPDATED) By arxiv.org Published On :: Quantum computing has evolved quickly in recent years and is showing significant benefits in a variety of fields. Malware analysis is one of those fields that could also take advantage of quantum computing. The combination of software used to locate the most frequent hashes and $n$-grams between benign and malicious software (KiloGram) and a quantum search algorithm could be beneficial, by loading the table of hashes and $n$-grams into a quantum computer, and thereby speeding up the process of mapping $n$-grams to their hashes. The first phase will be to use KiloGram to find the top-$k$ hashes and $n$-grams for a large malware corpus. From here, the resulting hash table is then loaded into a quantum machine. A quantum search algorithm is then used search among every permutation of the entangled key and value pairs to find the desired hash value. This prevents one from having to re-compute hashes for a set of $n$-grams, which can take on average $O(MN)$ time, whereas the quantum algorithm could take $O(sqrt{N})$ in the number of table lookups to find the desired hash values. Full Article
ow Towards Embodied Scene Description. (arXiv:2004.14638v2 [cs.RO] UPDATED) By arxiv.org Published On :: Embodiment is an important characteristic for all intelligent agents (creatures and robots), while existing scene description tasks mainly focus on analyzing images passively and the semantic understanding of the scenario is separated from the interaction between the agent and the environment. In this work, we propose the Embodied Scene Description, which exploits the embodiment ability of the agent to find an optimal viewpoint in its environment for scene description tasks. A learning framework with the paradigms of imitation learning and reinforcement learning is established to teach the intelligent agent to generate corresponding sensorimotor activities. The proposed framework is tested on both the AI2Thor dataset and a real world robotic platform demonstrating the effectiveness and extendability of the developed method. Full Article
ow The growth rate over trees of any family of set defined by a monadic second order formula is semi-computable. (arXiv:2004.06508v3 [cs.DM] UPDATED) By arxiv.org Published On :: Monadic second order logic can be used to express many classical notions of sets of vertices of a graph as for instance: dominating sets, induced matchings, perfect codes, independent sets or irredundant sets. Bounds on the number of sets of any such family of sets are interesting from a combinatorial point of view and have algorithmic applications. Many such bounds on different families of sets over different classes of graphs are already provided in the literature. In particular, Rote recently showed that the number of minimal dominating sets in trees of order $n$ is at most $95^{frac{n}{13}}$ and that this bound is asymptotically sharp up to a multiplicative constant. We build on his work to show that what he did for minimal dominating sets can be done for any family of sets definable by a monadic second order formula. We first show that, for any monadic second order formula over graphs that characterizes a given kind of subset of its vertices, the maximal number of such sets in a tree can be expressed as the extit{growth rate of a bilinear system}. This mostly relies on well known links between monadic second order logic over trees and tree automata and basic tree automata manipulations. Then we show that this "growth rate" of a bilinear system can be approximated from above.We then use our implementation of this result to provide bounds on the number of independent dominating sets, total perfect dominating sets, induced matchings, maximal induced matchings, minimal perfect dominating sets, perfect codes and maximal irredundant sets on trees. We also solve a question from D. Y. Kang et al. regarding $r$-matchings and improve a bound from G'orska and Skupie'n on the number of maximal matchings on trees. Remark that this approach is easily generalizable to graphs of bounded tree width or clique width (or any similar class of graphs where tree automata are meaningful). Full Article
ow Personal Health Knowledge Graphs for Patients. (arXiv:2004.00071v2 [cs.AI] UPDATED) By arxiv.org Published On :: Existing patient data analytics platforms fail to incorporate information that has context, is personal, and topical to patients. For a recommendation system to give a suitable response to a query or to derive meaningful insights from patient data, it should consider personal information about the patient's health history, including but not limited to their preferences, locations, and life choices that are currently applicable to them. In this review paper, we critique existing literature in this space and also discuss the various research challenges that come with designing, building, and operationalizing a personal health knowledge graph (PHKG) for patients. Full Article
ow Toward Improving the Evaluation of Visual Attention Models: a Crowdsourcing Approach. (arXiv:2002.04407v2 [cs.CV] UPDATED) By arxiv.org Published On :: Human visual attention is a complex phenomenon. A computational modeling of this phenomenon must take into account where people look in order to evaluate which are the salient locations (spatial distribution of the fixations), when they look in those locations to understand the temporal development of the exploration (temporal order of the fixations), and how they move from one location to another with respect to the dynamics of the scene and the mechanics of the eyes (dynamics). State-of-the-art models focus on learning saliency maps from human data, a process that only takes into account the spatial component of the phenomenon and ignore its temporal and dynamical counterparts. In this work we focus on the evaluation methodology of models of human visual attention. We underline the limits of the current metrics for saliency prediction and scanpath similarity, and we introduce a statistical measure for the evaluation of the dynamics of the simulated eye movements. While deep learning models achieve astonishing performance in saliency prediction, our analysis shows their limitations in capturing the dynamics of the process. We find that unsupervised gravitational models, despite of their simplicity, outperform all competitors. Finally, exploiting a crowd-sourcing platform, we present a study aimed at evaluating how strongly the scanpaths generated with the unsupervised gravitational models appear plausible to naive and expert human observers. Full Article
ow A predictive path-following controller for multi-steered articulated vehicles. (arXiv:1912.06259v5 [math.OC] UPDATED) By arxiv.org Published On :: Stabilizing multi-steered articulated vehicles in backward motion is a complex task for any human driver. Unless the vehicle is accurately steered, its structurally unstable joint-angle kinematics during reverse maneuvers can cause the vehicle segments to fold and enter a jack-knife state. In this work, a model predictive path-following controller is proposed enabling automatic low-speed steering control of multi-steered articulated vehicles, comprising a car-like tractor and an arbitrary number of trailers with passive or active steering. The proposed path-following controller is tailored to follow nominal paths that contains full state and control-input information, and is designed to satisfy various physical constraints on the vehicle states as well as saturations and rate limitations on the tractor's curvature and the trailer steering angles. The performance of the proposed model predictive path-following controller is evaluated in a set of simulations for a multi-steered 2-trailer with a car-like tractor where the last trailer has steerable wheels. Full Article
ow Measuring Social Bias in Knowledge Graph Embeddings. (arXiv:1912.02761v2 [cs.CL] UPDATED) By arxiv.org Published On :: It has recently been shown that word embeddings encode social biases, with a harmful impact on downstream tasks. However, to this point there has been no similar work done in the field of graph embeddings. We present the first study on social bias in knowledge graph embeddings, and propose a new metric suitable for measuring such bias. We conduct experiments on Wikidata and Freebase, and show that, as with word embeddings, harmful social biases related to professions are encoded in the embeddings with respect to gender, religion, ethnicity and nationality. For example, graph embeddings encode the information that men are more likely to be bankers, and women more likely to be homekeepers. As graph embeddings become increasingly utilized, we suggest that it is important the existence of such biases are understood and steps taken to mitigate their impact. Full Article
ow Towards a Proof of the Fourier--Entropy Conjecture?. (arXiv:1911.10579v2 [cs.DM] UPDATED) By arxiv.org Published On :: The total influence of a function is a central notion in analysis of Boolean functions, and characterizing functions that have small total influence is one of the most fundamental questions associated with it. The KKL theorem and the Friedgut junta theorem give a strong characterization of such functions whenever the bound on the total influence is $o(log n)$. However, both results become useless when the total influence of the function is $omega(log n)$. The only case in which this logarithmic barrier has been broken for an interesting class of functions was proved by Bourgain and Kalai, who focused on functions that are symmetric under large enough subgroups of $S_n$. In this paper, we build and improve on the techniques of the Bourgain-Kalai paper and establish new concentration results on the Fourier spectrum of Boolean functions with small total influence. Our results include: 1. A quantitative improvement of the Bourgain--Kalai result regarding the total influence of functions that are transitively symmetric. 2. A slightly weaker version of the Fourier--Entropy Conjecture of Friedgut and Kalai. This weaker version implies in particular that the Fourier spectrum of a constant variance, Boolean function $f$ is concentrated on $2^{O(I[f]log I[f])}$ characters, improving an earlier result of Friedgut. Removing the $log I[f]$ factor would essentially resolve the Fourier--Entropy Conjecture, as well as settle a conjecture of Mansour regarding the Fourier spectrum of polynomial size DNF formulas. Our concentration result has new implications in learning theory: it implies that the class of functions whose total influence is at most $K$ is agnostically learnable in time $2^{O(Klog K)}$, using membership queries. Full Article
ow A Fast and Accurate Algorithm for Spherical Harmonic Analysis on HEALPix Grids with Applications to the Cosmic Microwave Background Radiation. (arXiv:1904.10514v4 [math.NA] UPDATED) By arxiv.org Published On :: The Hierarchical Equal Area isoLatitude Pixelation (HEALPix) scheme is used extensively in astrophysics for data collection and analysis on the sphere. The scheme was originally designed for studying the Cosmic Microwave Background (CMB) radiation, which represents the first light to travel during the early stages of the universe's development and gives the strongest evidence for the Big Bang theory to date. Refined analysis of the CMB angular power spectrum can lead to revolutionary developments in understanding the nature of dark matter and dark energy. In this paper, we present a new method for performing spherical harmonic analysis for HEALPix data, which is a central component to computing and analyzing the angular power spectrum of the massive CMB data sets. The method uses a novel combination of a non-uniform fast Fourier transform, the double Fourier sphere method, and Slevinsky's fast spherical harmonic transform (Slevinsky, 2019). For a HEALPix grid with $N$ pixels (points), the computational complexity of the method is $mathcal{O}(Nlog^2 N)$, with an initial set-up cost of $mathcal{O}(N^{3/2}log N)$. This compares favorably with $mathcal{O}(N^{3/2})$ runtime complexity of the current methods available in the HEALPix software when multiple maps need to be analyzed at the same time. Using numerical experiments, we demonstrate that the new method also appears to provide better accuracy over the entire angular power spectrum of synthetic data when compared to the current methods, with a convergence rate at least two times higher. Full Article
ow ZebraLancer: Decentralized Crowdsourcing of Human Knowledge atop Open Blockchain. (arXiv:1803.01256v5 [cs.HC] UPDATED) By arxiv.org Published On :: We design and implement the first private and anonymous decentralized crowdsourcing system ZebraLancer, and overcome two fundamental challenges of decentralizing crowdsourcing, i.e., data leakage and identity breach. First, our outsource-then-prove methodology resolves the tension between the blockchain transparency and the data confidentiality to guarantee the basic utilities/fairness requirements of data crowdsourcing, thus ensuring: (i) a requester will not pay more than what data deserve, according to a policy announced when her task is published via the blockchain; (ii) each worker indeed gets a payment based on the policy, if he submits data to the blockchain; (iii) the above properties are realized not only without a central arbiter, but also without leaking the data to the open blockchain. Second, the transparency of blockchain allows one to infer private information about workers and requesters through their participation history. Simply enabling anonymity is seemingly attempting but will allow malicious workers to submit multiple times to reap rewards. ZebraLancer also overcomes this problem by allowing anonymous requests/submissions without sacrificing accountability. The idea behind is a subtle linkability: if a worker submits twice to a task, anyone can link the submissions, or else he stays anonymous and unlinkable across tasks. To realize this delicate linkability, we put forward a novel cryptographic concept, i.e., the common-prefix-linkable anonymous authentication. We remark the new anonymous authentication scheme might be of independent interest. Finally, we implement our protocol for a common image annotation task and deploy it in a test net of Ethereum. The experiment results show the applicability of our protocol atop the existing real-world blockchain. Full Article
ow A Local Spectral Exterior Calculus for the Sphere and Application to the Shallow Water Equations. (arXiv:2005.03598v1 [math.NA]) By arxiv.org Published On :: We introduce $Psimathrm{ec}$, a local spectral exterior calculus for the two-sphere $S^2$. $Psimathrm{ec}$ provides a discretization of Cartan's exterior calculus on $S^2$ formed by spherical differential $r$-form wavelets. These are well localized in space and frequency and provide (Stevenson) frames for the homogeneous Sobolev spaces $dot{H}^{-r+1}( Omega_{ u}^{r} , S^2 )$ of differential $r$-forms. At the same time, they satisfy important properties of the exterior calculus, such as the de Rahm complex and the Hodge-Helmholtz decomposition. Through this, $Psimathrm{ec}$ is tailored towards structure preserving discretizations that can adapt to solutions with varying regularity. The construction of $Psimathrm{ec}$ is based on a novel spherical wavelet frame for $L_2(S^2)$ that we obtain by introducing scalable reproducing kernel frames. These extend scalable frames to weighted sampling expansions and provide an alternative to quadrature rules for the discretization of needlet-like scale-discrete wavelets. We verify the practicality of $Psimathrm{ec}$ for numerical computations using the rotating shallow water equations. Our numerical results demonstrate that a $Psimathrm{ec}$-based discretization of the equations attains accuracy comparable to those of spectral methods while using a representation that is well localized in space and frequency. Full Article
ow Online Algorithms to Schedule a Proportionate Flexible Flow Shop of Batching Machines. (arXiv:2005.03552v1 [cs.DS]) By arxiv.org Published On :: This paper is the first to consider online algorithms to schedule a proportionate flexible flow shop of batching machines (PFFB). The scheduling model is motivated by manufacturing processes of individualized medicaments, which are used in modern medicine to treat some serious illnesses. We provide two different online algorithms, proving also lower bounds for the offline problem to compute their competitive ratios. The first algorithm is an easy-to-implement, general local scheduling heuristic. It is 2-competitive for PFFBs with an arbitrary number of stages and for several natural scheduling objectives. We also show that for total/average flow time, no deterministic algorithm with better competitive ratio exists. For the special case with two stages and the makespan or total completion time objective, we describe an improved algorithm that achieves the best possible competitive ratio $varphi=frac{1+sqrt{5}}{2}$, the golden ratio. All our results also hold for proportionate (non-flexible) flow shops of batching machines (PFB) for which this is also the first paper to study online algorithms. Full Article
ow CounQER: A System for Discovering and Linking Count Information in Knowledge Bases. (arXiv:2005.03529v1 [cs.IR]) By arxiv.org Published On :: Predicate constraints of general-purpose knowledge bases (KBs) like Wikidata, DBpedia and Freebase are often limited to subproperty, domain and range constraints. In this demo we showcase CounQER, a system that illustrates the alignment of counting predicates, like staffSize, and enumerating predicates, like workInstitution^{-1} . In the demonstration session, attendees can inspect these alignments, and will learn about the importance of these alignments for KB question answering and curation. CounQER is available at https://counqer.mpi-inf.mpg.de/spo. Full Article
ow How Can CNNs Use Image Position for Segmentation?. (arXiv:2005.03463v1 [eess.IV]) By arxiv.org Published On :: Convolution is an equivariant operation, and image position does not affect its result. A recent study shows that the zero-padding employed in convolutional layers of CNNs provides position information to the CNNs. The study further claims that the position information enables accurate inference for several tasks, such as object recognition, segmentation, etc. However, there is a technical issue with the design of the experiments of the study, and thus the correctness of the claim is yet to be verified. Moreover, the absolute image position may not be essential for the segmentation of natural images, in which target objects will appear at any image position. In this study, we investigate how positional information is and can be utilized for segmentation tasks. Toward this end, we consider {em positional encoding} (PE) that adds channels embedding image position to the input images and compare PE with several padding methods. Considering the above nature of natural images, we choose medical image segmentation tasks, in which the absolute position appears to be relatively important, as the same organs (of different patients) are captured in similar sizes and positions. We draw a mixed conclusion from the experimental results; the positional encoding certainly works in some cases, but the absolute image position may not be so important for segmentation tasks as we think. Full Article
ow AutoSOS: Towards Multi-UAV Systems Supporting Maritime Search and Rescue with Lightweight AI and Edge Computing. (arXiv:2005.03409v1 [cs.RO]) By arxiv.org Published On :: Rescue vessels are the main actors in maritime safety and rescue operations. At the same time, aerial drones bring a significant advantage into this scenario. This paper presents the research directions of the AutoSOS project, where we work in the development of an autonomous multi-robot search and rescue assistance platform capable of sensor fusion and object detection in embedded devices using novel lightweight AI models. The platform is meant to perform reconnaissance missions for initial assessment of the environment using novel adaptive deep learning algorithms that efficiently use the available sensors and computational resources on drones and rescue vessel. When drones find potential objects, they will send their sensor data to the vessel to verity the findings with increased accuracy. The actual rescue and treatment operation are left as the responsibility of the rescue personnel. The drones will autonomously reconfigure their spatial distribution to enable multi-hop communication, when a direct connection between a drone transmitting information and the vessel is unavailable. Full Article
ow Knowledge Enhanced Neural Fashion Trend Forecasting. (arXiv:2005.03297v1 [cs.IR]) By arxiv.org Published On :: Fashion trend forecasting is a crucial task for both academia and industry. Although some efforts have been devoted to tackling this challenging task, they only studied limited fashion elements with highly seasonal or simple patterns, which could hardly reveal the real fashion trends. Towards insightful fashion trend forecasting, this work focuses on investigating fine-grained fashion element trends for specific user groups. We first contribute a large-scale fashion trend dataset (FIT) collected from Instagram with extracted time series fashion element records and user information. Further-more, to effectively model the time series data of fashion elements with rather complex patterns, we propose a Knowledge EnhancedRecurrent Network model (KERN) which takes advantage of the capability of deep recurrent neural networks in modeling time-series data. Moreover, it leverages internal and external knowledge in fashion domain that affects the time-series patterns of fashion element trends. Such incorporation of domain knowledge further enhances the deep learning model in capturing the patterns of specific fashion elements and predicting the future trends. Extensive experiments demonstrate that the proposed KERN model can effectively capture the complicated patterns of objective fashion elements, therefore making preferable fashion trend forecast. Full Article
ow Avoiding 5/4-powers on the alphabet of nonnegative integers. (arXiv:2005.03158v1 [math.CO]) By arxiv.org Published On :: We identify the structure of the lexicographically least word avoiding 5/4-powers on the alphabet of nonnegative integers. Specifically, we show that this word has the form $p au(varphi(z) varphi^2(z) cdots)$ where $p, z$ are finite words, $varphi$ is a 6-uniform morphism, and $ au$ is a coding. This description yields a recurrence for the $i$th letter, which we use to prove that the sequence of letters is 6-regular with rank 188. More generally, we prove $k$-regularity for a sequence satisfying a recurrence of the same type. Full Article
ow An augmented Lagrangian preconditioner for implicitly-constituted non-Newtonian incompressible flow. (arXiv:2005.03150v1 [math.NA]) By arxiv.org Published On :: We propose an augmented Lagrangian preconditioner for a three-field stress-velocity-pressure discretization of stationary non-Newtonian incompressible flow with an implicit constitutive relation of power-law type. The discretization employed makes use of the divergence-free Scott-Vogelius pair for the velocity and pressure. The preconditioner builds on the work [P. E. Farrell, L. Mitchell, and F. Wechsung, SIAM J. Sci. Comput., 41 (2019), pp. A3073-A3096], where a Reynolds-robust preconditioner for the three-dimensional Newtonian system was introduced. The preconditioner employs a specialized multigrid method for the stress-velocity block that involves a divergence-capturing space decomposition and a custom prolongation operator. The solver exhibits excellent robustness with respect to the parameters arising in the constitutive relation, allowing for the simulation of a wide range of materials. Full Article
ow Catch Me If You Can: Using Power Analysis to Identify HPC Activity. (arXiv:2005.03135v1 [cs.CR]) By arxiv.org Published On :: Monitoring users on large computing platforms such as high performance computing (HPC) and cloud computing systems is non-trivial. Utilities such as process viewers provide limited insight into what users are running, due to granularity limitation, and other sources of data, such as system call tracing, can impose significant operational overhead. However, despite technical and procedural measures, instances of users abusing valuable HPC resources for personal gains have been documented in the past cite{hpcbitmine}, and systems that are open to large numbers of loosely-verified users from around the world are at risk of abuse. In this paper, we show how electrical power consumption data from an HPC platform can be used to identify what programs are executed. The intuition is that during execution, programs exhibit various patterns of CPU and memory activity. These patterns are reflected in the power consumption of the system and can be used to identify programs running. We test our approach on an HPC rack at Lawrence Berkeley National Laboratory using a variety of scientific benchmarks. Among other interesting observations, our results show that by monitoring the power consumption of an HPC rack, it is possible to identify if particular programs are running with precision up to and recall of 95\% even in noisy scenarios. Full Article
ow Robust Trajectory and Transmit Power Optimization for Secure UAV-Enabled Cognitive Radio Networks. (arXiv:2005.03091v1 [cs.IT]) By arxiv.org Published On :: Cognitive radio is a promising technology to improve spectral efficiency. However, the secure performance of a secondary network achieved by using physical layer security techniques is limited by its transmit power and channel fading. In order to tackle this issue, a cognitive unmanned aerial vehicle (UAV) communication network is studied by exploiting the high flexibility of a UAV and the possibility of establishing line-of-sight links. The average secrecy rate of the secondary network is maximized by robustly optimizing the UAV's trajectory and transmit power. Our problem formulation takes into account two practical inaccurate location estimation cases, namely, the worst case and the outage-constrained case. In order to solve those challenging non-convex problems, an iterative algorithm based on $mathcal{S}$-Procedure is proposed for the worst case while an iterative algorithm based on Bernstein-type inequalities is proposed for the outage-constrained case. The proposed algorithms can obtain effective suboptimal solutions of the corresponding problems. Our simulation results demonstrate that the algorithm under the outage-constrained case can achieve a higher average secrecy rate with a low computational complexity compared to that of the algorithm under the worst case. Moreover, the proposed schemes can improve the secure communication performance significantly compared to other benchmark schemes. Full Article
ow Learning, transferring, and recommending performance knowledge with Monte Carlo tree search and neural networks. (arXiv:2005.03063v1 [cs.LG]) By arxiv.org Published On :: Making changes to a program to optimize its performance is an unscalable task that relies entirely upon human intuition and experience. In addition, companies operating at large scale are at a stage where no single individual understands the code controlling its systems, and for this reason, making changes to improve performance can become intractably difficult. In this paper, a learning system is introduced that provides AI assistance for finding recommended changes to a program. Specifically, it is shown how the evaluative feedback, delayed-reward performance programming domain can be effectively formulated via the Monte Carlo tree search (MCTS) framework. It is then shown that established methods from computational games for using learning to expedite tree-search computation can be adapted to speed up computing recommended program alterations. Estimates of expected utility from MCTS trees built for previous problems are used to learn a sampling policy that remains effective across new problems, thus demonstrating transferability of optimization knowledge. This formulation is applied to the Apache Spark distributed computing environment, and a preliminary result is observed that the time required to build a search tree for finding recommendations is reduced by up to a factor of 10x. Full Article