pr 5 Product Image Tips For High Converting Landing Pages By dailyblogtips.com Published On :: Tue, 21 May 2019 10:50:55 +0000 They say that a picture is worth a thousand words, but have you ever stopped to think what your Ecommerce images are saying about the products you’re trying to sell online? Are your photos helping your products to jump off the screen and convince shoppers to buy them? Or, are your product images quite simply […] Original post: 5 Product Image Tips For High Converting Landing Pages The post 5 Product Image Tips For High Converting Landing Pages appeared first on Daily Blog Tips. Full Article Blog Design
pr Best Alexa Skills That Will Actually Surprise You By dailyblogtips.com Published On :: Thu, 31 Oct 2019 17:19:12 +0000 Technology has changed the way we live. A few decades back, we couldn’t even imagine making a video call to a person sitting in another corner of the world. With every technological advancement, mankind is treading towards greater development. From smart gadgets to machines, every invention has leveraged the human lifestyle. There’s no doubt in […] Original post: Best Alexa Skills That Will Actually Surprise You The post Best Alexa Skills That Will Actually Surprise You appeared first on Daily Blog Tips. Full Article Internet Marketing
pr Download the new Xtreme One WordPress Framework for free and test now! By wpengineer.com Published On :: Mon, 28 Oct 2013 16:45:57 +0000 With pleasure we can now announce that Xtreme One 1.6 was released as a beta last week! Xtreme One WordPress […] Full Article WordPress News WordPress Themes WordPress WordPress Theme WordPress Widget Xtreme One
pr Every Day A Post of WordPress Tips and Tricks until Christmas! By wpengineer.com Published On :: Thu, 28 Nov 2013 14:51:16 +0000 The time has come and our loyal reader know already our traditional Advents Calendar. For the people who don’t know, […] Full Article WPengineer Misc
pr New hooks in WordPress 3.8 By wpengineer.com Published On :: Mon, 16 Dec 2013 10:00:53 +0000 WordPress 3.8 introduced one new action and five new filters: automatic_updates_complete Action triggered after all automatic updates have run. (wp-admin/includes/class-wp-upgrader.php) […] Full Article WordPress Plugins action filter hooks
pr Download older plugin versions from wordpress.org By wpengineer.com Published On :: Mon, 16 Mar 2015 10:00:05 +0000 So you’ve updated your plugins… … and your blog doesn’t work anymore … and you have no backup … … […] Full Article WPengineer Misc
pr Download older plugin versions from wordpress.org By wpengineer.com Published On :: Thu, 14 Sep 2017 11:56:00 +0000 There’s a simple way to get hold of previous versions of your WordPress plugins, for example if a current version […] Full Article WordPress Plugins plugins
pr School District Switches to Local and Organic Meals, Cuts Carbon Footprint—and Saves Money By feedproxy.google.com Published On :: Tue, 23 May 2017 20:01:39 +0000 By Melissa Hellmann Yes! Magazine A new report revealed surprising results when Oakland overhauled its lunch menu at 100-plus schools by serving less meat and more fruits and vegetables. When her eldest son was in elementary school in the Oakland … Continue reading → Full Article Food eat local nutrition school lunch
pr Mobility Pricing Relieves Congestion, Helps People Breathe Easier By feedproxy.google.com Published On :: Fri, 01 Jun 2018 19:54:22 +0000 By David Suzuki with contributions from Senior Editor Ian Hanington David Suzuki Foundation By 2002, drivers in London, England, were spending as much as half their commuting time stalled in traffic, contributing to much of the city centre’s dangerous particulate … Continue reading → Full Article Transportation air pollution auto emissions Commuting Eco-Conscious Drivers Transport for London
pr Top Colorado Republican Pressures Official to Report False Election Results By feeds.drudge.com Published On :: Sat, 09 May 2020 11:33:22 -0400 U.S. Rep. Ken Buck, who is also the chairman of the Colorado Republican Party, was captured ordering a local party official to report false election results in a primary race for a state Senate seat in a leaked audio recording released earlier this week. Full Article news
pr Self Reliance + Personal Uprising with John Jantsch By feedproxy.google.com Published On :: Wed, 13 Nov 2019 14:01:38 +0000 John Jantsch is a veteran marketer. He’s written several bestselling books including Duct Tape Marketing and The Referral Engine. He’s out with a new book called the Self-Reliant Entrepreneur: 366 Daily Meditations to Feed Your Soul and Grow Your Business As you might know, I’m a bit of a fan of daily habits, so of course John gives us a little preview into some of the daily explorations of thoughts and writings from notable American authors. Of course, that’s not all… we also get into: We go deep into following your own path and listening to your intuition. What we can learn from rabble rousers of our history and those who embraced counter culture to follow their own beliefs. The role that self-awareness has in pursuing our dreams. and much more. Enjoy! FOLLOW JOHN: facebook | twitter | website Listen to the Podcast Subscribe 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, craft/maker, money/life and the ability to make a living in any of those disciplines. They are high quality, highly curated classes taught by the world’s top experts — Pulitzer, Oscar, Grammy Award winners, New […] The post Self Reliance + Personal Uprising with John Jantsch appeared first on Chase Jarvis Photography. Full Article Business chasejarvisLIVE Podcast Counter Culture Inspiration marketing meditation
pr Why's it so hard to get the cool stuff approved? By feedproxy.google.com Published On :: Thu, 27 Feb 2020 00:00:00 -0500 The classic adage is “good design speaks for itself.” Which would mean that if something’s as good of an idea as you think it is, a client will instantly see that it’s good too, right? Here at Viget, we’re always working with new and different clients. Each with their own challenges and sensibilities. But after ten years of client work, I can’t help but notice a pattern emerge when we’re trying to get approval on especially cool, unconventional parts of a design. So let’s break down some of those patterns to hopefully better understand why clients hesitate, and what strategies we’ve been using lately to help get the work we’re excited about approved.Imagine this: the parallax homepage with elements that move around in surprising ways or a unique navigation menu that conceptually reinforces a site’s message. The way the content cards on a page will, like, be literal cards that will shuffle and move around. Basically, any design that feels like an exciting, novel challenge, will need the client to “get it.” And that often turns out to be the biggest challenge of all. There are plenty of practical reasons cool designs get shot down. A client is usually more than one stakeholder, and more than the team of people you’re working with directly. On any project, there’s an amount of telephone you end up playing. Or, there’s always the classic foes: budgets and deadlines. Any idea should fit in those predetermined constraints. But as a project goes along, budgets and deadlines find a way to get tighter than you planned. But innovative designs and interactions can seem especially scary for clients to approve. There’s three fears that often pop up on projects:The fear of change. Maybe the client expected something simple, a light refresh. Something that doesn’t challenge their design expectations or require more time and effort to understand. And on our side, maybe we didn’t sufficiently ease them into our way of thinking and open them up to why we think something bigger and bolder is the right solution for them. Baby steps, y’all. The fear of the unknown. Or, less dramatically, a lack of understanding of the medium. In the past, we have struggled with how to present an interactive, animated design to a client before it’s actually built. Looking at a site that does something conceptually similar as an example can be tough. It’s asking a lot of a client’s imagination to show them a site about boots that has a cool spinning animation and get meaningful feedback about how a spinning animation would work on their site about after-school tutoring. Or maybe we’ve created static designs, then talked around what we envision happening. Again, what seems so clear in our minds as professionals entrenched in this stuff every day can be tough for someone outside the tech world to clearly understand. The fear of losing control. We’re all about learning from past mistakes. So lets say, after dealing with that fear of the unknown on a project, next time you go in the opposite direction. You invest time up front creating something polished. Maybe you even get the developer to build a prototype that moves and looks like the real thing. You’ve taken all the vague mystery out of the process, so a client will be thrilled, right? Surprise, probably not! Most clients are working with you because they want to conquer the noble quest that is their redesign together. When we jump straight to showing something that looks polished, even if it’s not really, it can feel like we jumped ahead without keeping them involved. Like we took away their input. They can also feel demotivated to give good, meaningful feedback on a polished prototype because it looks “done.”So what to do? Lately we have found low-fidelity prototypes to be a great tool for combating these fears and better communicating our ideas. What are low-fidelity prototypes?Low fidelity prototypes are a tool that designers can create quickly to illustrate an idea, without sinking time into making it pixel-perfect. Some recent examples of prototypes we've created include a clickable Figma or Invision prototype put together with Whimsical wireframes: A rough animation created in Principle illustrating less programatic animation: And even creating an animated storyboard in Photoshop: They’re rough enough that there’s no way they could be confused for a final product. But customized so that a client can immediately understand what they’re looking at and what they need to respond to. Low-fidelity prototypes hit a sweet spot that addresses those client fears head on. That fear of change? A lo-fi prototype starts rough and small, so it can ease a client into a dramatic change without overwhelming them. It’s just a first step. It gives them time to react and warm up to something that’ll ultimately be a big change.It also cuts out the fear of the unknown. Seeing something moving around, even if it’s rough, can be so much more clear than talking ourselves in circles about how we think it will move, and hoping the client can imagine it. The feature is no longer an enigma cloaked in mystery and big talk, but something tangible they can point at and ask concrete questions about.And finally, a lo-fi prototype doesn’t threaten a client’s sense of control. Low-fidelity means it’s clearly still a work in progress! It’s just an early step in the creative process, and therefore communicates that we’re still in the middle of that process together. There’s still plenty of room for their ideas and feedback. Lo-fi prototypes: client-tested, internal team-approvedThere are a lot of reasons to love lo-fi prototypes internally, too! They’re quick and easy. We can whip up multiple ideas within a few hours, without sinking the time into getting our hearts set on any one thing. In an agency setting especially, time is limited, so the faster we can get an idea out of our own heads, the better.They’re great to share with developers. Ideally, the whole team is working together simultaneously, collaborating every step of the way. Realistically, a developer often doesn’t have time during a project’s early design phase. Lo-fi prototypes are concrete enough that a developer can quickly tell if building an idea will be within scope. It helps us catch impractical ideas early and helps us all collaborate to create something that’s both cool and feasible. Stay tuned for posts in the near future diving into some of our favorite processes for creating lo-fi prototypes! Full Article Design & Content
pr Setting New Project Managers Up for Success By feedproxy.google.com Published On :: Wed, 11 Mar 2020 08:00:00 -0400 At Viget, we’ve brought on more than a few new Project Managers over the past couple of years, as we continue to grow. The awesome new people we’ve hired have ranged in their levels of experience, but some of them are earlier in their careers and need support from more experienced PMs to develop their skills and flourish. We have different levels of training and support for new PMs. These broadly fall into four categories: Onboarding: Learning about Viget tools and processesShadowing: Learning by watching othersPairing: Learning by doing collaborativelyLeading: Learning by doing solo Onboarding In addition to conducting intro sessions to each discipline at Viget, new Viget PMs go through a lengthy set of training sessions that are specific to the PM lab. These include intros to: PM tools and resourcesProject processesProject typesProject checklistsProject taskingProject planningBudgets, schedules, and resourcingRetrospectivesWorking with remote teamsProject kickoffsThinking about developmentGithub and development workflowTickets, definition, and documentationQA testingAccount management Shadowing After PMs complete the onboarding process, they start shadowing other PMs’ projects to get exposure to the different types of projects we run (since the variety is large). We cater length and depth of shadowing based on how much experience a PM has coming in. We also try to expose PMs to multiple project managers, so they can see how PM style differs person-to-person. We’ve found that it can be most effective to have PMs shadow activities that are more difficult to teach in theory, such as shadowing a PM having a difficult conversation with a client, or shadowing a front-end build-out demo to see how the PM positions the meeting and our process to the client. More straightforward tasks like setting up a Harvest project could be done via pairing, since it’s easy to get the hang of with a little guidance. Pairing While shadowing is certainly helpful, we try to get PMs into pairing mode pretty quickly, since we’ve found that most folks learn better by doing than by watching. Sometimes this might mean having a new PM setting up an invoice or budget sheet for a client while a more experienced PM sits next to them, talking them through the process. We’ve found that having a newer PM lead straightforward activities with guidance tends to be more effective than the newer PM merely watching the more experienced PM do that activity. Another tactic we take is to have both PMs complete a task independently, and then meet and talk through their work, with the more experienced PM giving the less experienced PM feedback. That helps the newer PM think through a task on their own, and gain experience, but still have the chance to see how someone else would have approached the task and get meaningful feedback. Leading Once new PMs are ready to be in the driver’s seat, they are staffed as the lead on projects. The timing of when someone shifts into a lead role depends on how much prior experience that person has, as well as what types of projects are actively ready to be worked on. Most early-career project managers have a behind-the-scenes project mentor (another PM) on at least their first couple projects, so they have a dedicated person to ask questions and get advice from who also has more detailed context than that person’s manager would. For example, mentors often shadow key client and internal meetings and have more frequent check-ins with mentees. This might be less necessary at a company where all the projects are fairly similar, but at Viget, our projects vary widely in scale and services provided, as well as client needs. Because of this, there’s no “one size fits all” process and we have a significant amount of customization per project, which can be daunting to new PMs who are still getting the hang of things. For these mentorship pairings, we use a mentorship plan document (template here) to help the mentor and mentee work together to define goals, mentorship focuses, and touchpoints. Sometimes the mentee’s manager will take a first stab at filling out the plan, other times, the mentor will start that process. Management Touchpoints Along the way, we make sure new PMs have touchpoints with their managers to get the level of support they need to grow and succeed. Managers have regular 1:1s with PMs that are referred to as “project 1:1s”, and are used for the managee to talk through and get advice on challenges or questions related to the projects they’re working on—though really, they can be used for whatever topics are on the managee’s mind. PMs typically have 1:1s with managers daily the first week, two to three times per week after that for the first month or so, then scale down to once per week, and then scale down to bi-weekly after the first six months. In addition to project 1:1s, we also have monthly 1:1s that are more bigger-picture and focused on goal-setting and progress, project feedback from that person’s peers, reflection on how satisfied and fulfilled they’re feeling in their role, and talking through project/industry interests which informs what projects we should advocate for them to be staffed on. We have a progress log template that we customize per PM to keep track of goals and progress. We try to foster a supportive environment that encourages growth, feedback, and experiential learning, but also that lets folks have the autonomy to get in the driver’s seat as soon as they’re comfortable. Interested in learning more about what it’s like to work at Viget? Check out our open positions here. Full Article Process Project Management
pr TrailBuddy: Using AI to Create a Predictive Trail Conditions App By feedproxy.google.com Published On :: Thu, 19 Mar 2020 08:00:00 -0400 Viget is full of outdoor enthusiasts and, of course, technologists. For this year's Pointless Weekend, we brought these passions together to build TrailBuddy. This app aims to solve that eternal question: Is my favorite trail dry so I can go hike/run/ride? While getting muddy might rekindle fond childhood memories for some, exposing your gear to the elements isn’t great – it’s bad for your equipment and can cause long-term, and potentially expensive, damage to the trail. There are some trail apps out there but we wanted one that would focus on current conditions. Currently, our favorites trail apps, like mtbproject.com, trailrunproject.com, and hikingproject.com -- all owned by REI, rely on user-reported conditions. While this can be effective, the reports are frequently unreliable, as condition reports can become outdated in just a few days. Our goal was to solve this problem by building an app that brought together location, soil type, and weather history data to create on-demand condition predictions for any trail in the US. We built an initial version of TrailBuddy by tapping into several readily-available APIs, then running the combined data through a machine learning algorithm. (Oh, and also by bringing together a bunch of smart and motivated people and combining them with pizza and some of the magic that is our Pointless Weekends. We'll share the other Pointless Project, Scurry, with you soon.) Learn More We're hiring Front-End Developers in our Boulder, Chattanooga, Durham, Falls Church and Remote (U.S. Only) offices. Learn more and introduce yourself. The quest for data. We knew from the start this app would require data from a number of sources. As previously mentioned, we used REI’s APIs (i.e. https://www.hikingproject.com/data) as the source for basic trail information. We used the trails’ latitude and longitude coordinates as well as its elevation to query weather and soil type. We also found data points such as a trail’s total distance to be relevant to our app users and decided to include that on the front-end, too. Since we wanted to go beyond relying solely on user-reported metrics, which is how REI’s current MTB project works, we came up with a list of factors that could affect the trail for that day. First on that list was weather. We not only considered the impacts of the current forecast, but we also looked at the previous day’s forecast. For example, it’s safe to assume that if it’s currently raining or had been raining over the last several days, it would likely lead to muddy and unfavorable conditions for that trail. We utilized the DarkSky API (https://darksky.net/dev) to get the weather forecasts for that day, as well as the records for previous days. This included expected information, like temperature and precipitation chance. It also included some interesting data points that we realized may be factors, like precipitation intensity, cloud cover, and UV index. But weather alone can’t predict how muddy or dry a trail will be. To determine that for sure, we also wanted to use soil data to help predict how well a trail’s unique soil composition recovers after precipitation. Similar amounts of rain on trails of very different soil types could lead to vastly different trail conditions. A more clay-based soil would hold water much longer, and therefore be much more unfavorable, than loamy soil. Finding a reliable source for soil type and soil drainage proved incredibly difficult. After many hours, we finally found a source through the USDA that we could use. As a side note—the USDA keeps track of lots of data points on soil information that’s actually pretty interesting! We can’t say we’re soil experts but, we felt like we got pretty close. We used Whimsical to build our initial wireframes. Putting our design hats on. From the very first pitch for this app, TrailBuddy’s main differentiator to peer trail resources is its ability to surface real-time information, reliably, and simply. For as complicated as the technology needed to collect and interpret information, the front-end app design needed to be clean and unencumbered. We thought about how users would naturally look for information when setting out to find a trail and what factors they’d think about when doing so. We posed questions like: How easy or difficult of a trail are they looking for?How long is this trail?What does the trail look like?How far away is the trail in relation to my location?For what activity am I needing a trail for? Is this a trail I’d want to come back to in the future? By putting ourselves in our users’ shoes we quickly identified key features TrailBuddy needed to have to be relevant and useful. First, we needed filtering, so users could filter between difficulty and distance to narrow down their results to fit the activity level. Next, we needed a way to look up trails by activity type—mountain biking, hiking, and running are all types of activities REI’s MTB API tracks already so those made sense as a starting point. And lastly, we needed a way for the app to find trails based on your location; or at the very least the ability to find a trail within a certain distance of your current location. We used Figma to design, prototype, and gather feedback on TrailBuddy. Using machine learning to predict trail conditions. As stated earlier, none of us are actual soil or data scientists. So, in order to achieve the real-time conditions reporting TrailBuddy promised, we’d decided to leverage machine learning to make predictions for us. Digging into the utility of machine learning was a first for all of us on this team. Luckily, there was an excellent tutorial that laid out the basics of building an ML model in Python. Provided a CSV file with inputs in the left columns, and the desired output on the right, the script we generated was able to test out multiple different model strategies, and output the effectiveness of each in predicting results, shown below. We assembled all of the historical weather and soil data we could find for a given latitude/longitude coordinate, compiled a 1000 * 100 sized CSV, ran it through the Python evaluator, and found that the CART and SVM models consistently outranked the others in terms of predicting trail status. In other words, we found a working model for which to run our data through and get (hopefully) reliable predictions from. The next step was to figure out which data fields were actually critical in predicting the trail status. The more we could refine our data set, the faster and smarter our predictive model could become. We pulled in some Ruby code to take the original (and quite massive) CSV, and output smaller versions to test with. Now again, we’re no data scientists here but, we were able to cull out a good majority of the data and still get a model that performed at 95% accuracy. With our trained model in hand, we could serialize that to into a model.pkl file (pkl stands for “pickle”, as in we’ve “pickled” the model), move that file into our Rails app along with it a python script to deserialize it, pass in a dynamic set of data, and generate real-time predictions. At the end of the day, our model has a propensity to predict fantastic trail conditions (about 99% of the time in fact…). Just one of those optimistic machine learning models we guess. Where we go from here. It was clear that after two days, our team still wanted to do more. As a first refinement, we’d love to work more with our data set and ML model. Something that was quite surprising during the weekend was that we found we could remove all but two days worth of weather data, and all of the soil data we worked so hard to dig up, and still hit 95% accuracy. Which … doesn’t make a ton of sense. Perhaps the data we chose to predict trail conditions just isn’t a great empirical predictor of trail status. While these are questions too big to solve in just a single weekend, we'd love to spend more time digging into this in a future iteration. Full Article News & Culture
pr Our WFH Best Practices By feedproxy.google.com Published On :: Fri, 20 Mar 2020 08:00:00 -0400 Our first remote office opened in 2007 when a designer and a developer left our HQ office and moved to Durham. Ever since we've been fine-tuning our ability to collaborate across locations. Today, we have team members across the country in our four offices, and we have fully remote employees in Charleston, Kansas City, New York City, Dallas, and Charlottesville. Because of the coronavirus outbreak, a lot of people recently started working from their homes across the world, the country, and Viget. We wanted to share some of our best practices for being great teammates and doing great work, regardless of locale, and we’d love to hear yours in the comments. Communicate Often and Write It Down We want every person at Viget to be informed and connected. We do this in a few ways. We have a company Knowledge Base, which contains critical information including HR policies, office processes, brand guidelines, project resources, etc. We also have a well-organized Google Drive that everyone can access. Learn More We're hiring Front-End Developers in our Boulder, Chattanooga, Durham, Falls Church and Remote (U.S. Only) offices. Learn more and introduce yourself. My favorite communication tool we use, however, is our Internal Lab Report. Every week, we create a Google Doc with HR updates, birthdays, upcoming events we’re attending, relevant publicity we or a client received, and timely updates on projects, sales, and recruiting. This report allows the entire team to have the same information, regardless of PTO schedules, and it provides a record that can be referenced weeks, months, or years later. I have also found our Slack habits really helpful. We try to make our availability easily known, mostly via a passive Slack status. We each update our status daily, sometimes multiple times, so people can see if we’re working from home, out of the office for an appointment, in a meeting, or offline for a personal phone call. We also have a few Slack Channels we use very specifically to announce PTO, important announcements, and recently, one that is specific to the updating coronavirus situation. My work from home station. Figure Out Your Boundaries This looks different for everyone and can be an ever-changing target. Understanding your boundaries requires you to be honest with yourself – Are you easily distracted? Can you successfully work in pajama pants? Will your dog actually allow you to get work done? Does working from the couch result in good work, or do you need a designated work spot? For some, working from home requires setting boundaries to ensure the work gets done. For others, working from home requires setting a start and stop times to ensure you don’t overwork yourself. Viget has a flexible work policy, so many of us work from home fairly often and have gotten our routines set up. As such, we have written about this before! Check out Trevor’s article about working remotely.Show Your Face When I first started at Viget, I’d never worked anywhere that used a Google Hangout for nearly every meeting. At first, I was tempted to call into meetings and leave the camera off because I found it exposing. Now, I can’t imagine not using it, and I’ve even embraced it in my personal life with friends and family. I realized the value in face-to-face conversations even in virtual form, the ability to see body language, and the connection you establish when you see each other's faces — even if your hair isn't perfect or you haven't arranged your plants just-so in the view behind you. Whenever possible, use your camera during a meeting. It increases trust, communication, and in my personal-not-backed-by-science-opinion, lightness, which frankly, I think we can all use a bit more of right now. Here's a screen shot from our Saint Patrick's Day Happy Hour. Create Shared Experiences As a company with project teams often distributed across our four locations, cross-office experiences are vital to our culture, and we’ve spent years working to keep our remote offices in sync. A few of our ongoing group activities include a monthly virtual Book Club, our weekly full-team Free Lunch Friday tradition, Donut for Slack, and, of course, our Pointless Weekends. The current global health crisis now requires almost all of the company to work remote, so we’ve gotten creative with our attempts to increase non-project time together, in order to keep up the vibes we’ve worked hard to create. What we’ve recently started: Last Weekend this Morning - Monday mornings, we have an optional virtual coffee, where anyone who’d like to chat can join and share the latest gardening lesson or bingeable tv show. It lets us start our week off as we would when we’re all in the office — saying hello to each other.Virtual Happy Hours - We are a company that likes to socialize, and a bit of distance doesn’t stop us. This week, we set up an after-hours Happy Hour for St. Patrick’s Day.Daily Lunch Table- If you’ve ever visited our HQ office in Falls Church, you’ll notice our large kitchen table. We have an informal tradition of gathering around noon to eat together, whether it’s just a couple folks or the whole team. We now do this lunch virtually. So far, we’re mostly taking turns discussing who is eating what, and of course, sharing said recipes. I crowdsourced some ideas from the Viget team, and here are some noteworthy takeaways: "In remote meetings, minimize all your other windows and be fully present. It’s easy to allow your attention to accidentally drift if you see a new Slack channel light up, especially if you’re in a larger meeting. Suddenly, you find yourself multitasking. Treat the meeting as if you were there in person: unless you’re taking notes, minimize your other tabs, and give the conversation your full attention." - Paul Koch “I try to reach out to more folks I don’t consistently work with. Since there’s less interaction in general, I want to be more intentional about staying connected.” - Laura Sweltz “Good habits are hard to form and bad habits are hard to break, and it’s often hard to find the right time to make a change. Most of us are experiencing a disruption to our usual behaviors right now, but that doesn’t have to be entirely bad. Be deliberate now and when this is over, we might all end up with some new work habits worth keeping.” - Emily Bloom “I’ve found it helpful to create a physical space similar to the one I had at work. While this isn’t exactly possible, small things like setting up a laptop stand and second screen make it so I’m less likely to get distracted and wander to the couch or kitchen (aka the snack danger zone.).” - Aubrey Lear “It’s easy to get stuck in one spot all day, so be proactive about moving around, or creating excuses to do so. Whether that’s making yourself a cup of coffee, eating lunch away from your computer, or going for a quick walk outside for some fresh air. This will help reduce the risk of going stir crazy.” -Zach Robbins True to Viget form, our remote work is all about “Progress, Not Perfection.” While remote collaboration is ingrained in our company, we’re looking for opportunities to fine-tune our approach and improve our habits. We’d love to hear from you: What are your best practices? Lessons learned? Full Article Process
pr CLI Equivalents for Common MAMP PRO and Sequel Pro Tasks By feedproxy.google.com Published On :: Thu, 26 Mar 2020 00:00:00 -0400 Working on website front ends I sometimes use MAMP PRO to manage local hosts and Sequel Pro to manage databases. Living primarily in my text editor, a terminal, and a browser window, moving to these click-heavy dedicated apps can feel clunky. Happily, the tasks I have most frequently turned to those apps for —starting and stopping servers, creating new hosts, and importing, exporting, deleting, and creating databases— can be done from the command line. I still pull up MAMP PRO if I need to change a host's PHP version or work with its other more specialized settings, or Sequel Pro to quickly inspect a database, but for the most part I can stay on the keyboard and in my terminal. Here's how: Command Line MAMP PRO You can start and stop MAMP PRO's servers from the command line. You can even do this when the MAMP PRO desktop app isn't open. Note: MAMP PRO's menu icon will not change color to reflect the running/stopped status when the status is changed via the command line. Start the MAMP PRO servers: /Applications/MAMP PRO.app/Contents/MacOS/MAMP PRO cmd startServers Stop the MAMP PRO servers: /Applications/MAMP PRO.app/Contents/MacOS/MAMP PRO cmd stopServers Create a host (replace host_name and root_path): /Applications/MAMP PRO.app/Contents/MacOS/MAMP PRO cmd createHost host_name root_path MAMP PRO-friendly Command Line Sequel Pro Note: if you don't use MAMP PRO, just replace the /Applications/MAMP/Library/bin/mysql with mysql. In all of the following commands, replace username with your user name (locally this is likely root) and database_name with your database name. The -p (password) flag with no argument will trigger an interactive password prompt. This is more secure than including your password in the command itself (like -pYourPasswordHere). Of course, if you're using the default password root is not particular secure to begin with so you might just do -pYourPasswordHere. Setting the -h (host) flag to localhost or 127.0.0.1 tells mysql to look at what's on localhost. With the MAMP PRO servers running, that will be the MAMP PRO databases. # with the MAMP PRO servers running, these are equivalent: # /Applications/MAMP/Library/bin/mysql -h 127.0.0.1 other_options # and # /Applications/MAMP/Library/bin/mysql -h localhost other_options /Applications/MAMP/Library/bin/mysql mysql_options # enter. opens an interactive mysql session mysql> some command; # don't forget the semicolon mysql> exit; Create a local database # with the MAMP PRO servers running # replace `username` with your username, which is `root` by default /Applications/MAMP/Library/bin/mysql -h localhost -u username -p -e "create database database_name" or # with the MAMP PRO servers running # replace `username` (`root` by default) and `database_name` /Applications/MAMP/Library/bin/mysql -h localhost -u username -p # and then enter mysql> create database database_name; # don't forget the semicolon mysql> exit MAMP PRO's databases are stored in /Library/Application Support/appsolute/MAMP PRO/db so to confirm that it worked you can ls /Library/Application Support/appsolute/MAMP PRO/db # will output the available mysql versions. For example I have mysql56_2018-11-05_16-25-13 mysql57 # If it isn't clear which one you're after, open the main MAMP PRO and click # on the MySQL "servers and services" item. In my case it shows "Version: 5.7.26" # Now look in the relevant MySQL directory ls /Library/Application Support/appsolute/MAMP PRO/db/mysql57 # the newly created database should be in the list Delete a local database # with the MAMP PRO servers running # replace `username` (`root` by default) and `database_name` /Applications/MAMP/Library/bin/mysql -h localhost -u username -p -e "drop database database_name" Export a dump of a local database. Note that this uses mysqldump not mysql. # to export an uncompressed file # replace `username` (`root` by default) and `database_name` /Applications/MAMP/Library/bin/mysqldump -h localhost -u username -p database_name > the/output/path.sql # to export a compressed file # replace `username` (`root` by default) and `database_name` /Applications/MAMP/Library/bin/mysqldump -h localhost -u username -p database_name | gzip -c > the/output/path.gz Export a local dump from an external database over SSH. Note that this uses mysqldump not mysql. # replace `ssh-user`, `ssh_host`, `mysql_user`, `database_name`, and the output path # to end up with an uncompressed file ssh ssh_user@ssh_host "mysqldump -u mysql_user -p database_name | gzip -c" | gunzip > the/output/path.sql # to end up with a compressed file ssh ssh_user@ssh_host "mysqldump -u mysql_user -p database_name | gzip -c" > the/output/path.gz Import a local database dump into a local database # with the MAMP PRO servers running # replace `username` (`root` by default) and `database_name` /Applications/MAMP/Library/bin/mysql -h localhost -u username -p database_name < the/dump/path.sql Import a local database dump into a remote database over SSH. Use care with this one. But if you are doing it with Sequel Pro —maybe you are copying a Craft site's database from a production server to a QA server— you might as well be able to do it on the command line. ssh ssh_user@ssh_host "mysql -u username -p remote_database_name" < the/local/dump/path.sql For me, using the command line instead of the MAMP PRO and Sequel Pro GUI means less switching between keyboard and mouse, less opening up GUI features that aren't typically visible on my screen, and generally better DX. Give it a try! And while MAMP Pro's CLI is limited to the essentials, command line mysql of course knows no limits. If there's something else you use Sequel Pro for, you may be able to come up with a mysql CLI equivalent you like even better. Full Article Code Front-end Engineering Back-end Engineering
pr Pursuing A Professional Certification In Scrum By feedproxy.google.com Published On :: Wed, 22 Apr 2020 08:00:00 -0400 Professional certifications have become increasingly popular in this age of career switchers and the freelance gig economy. A certification can be a useful way to advance your skill set quickly or make your resume stand out, which can be especially important for those trying to break into a new industry or attract business while self-employed. Whatever your reason may be for pursuing a professional certificate, there is one question only you can answer for yourself: is it worth it? Finding first-hand experiences from professionals with similar career goals and passions was the most helpful research I used to answer that question for myself. So, here’s mine; why I decided to get Scrum certified, how I evaluated my options, and if it was really worth it. A shift in mindset My background originates in brand strategy where it’s typical for work to follow a predictable order, each step informing the next. This made linear techniques like water-fall timelines, completing one phase of work in its entirety before moving onto the next, and documenting granular tasks weeks in advance helpful and easy to implement. When I made the move to more digitally focused work, tasks followed a much looser set of ‘typical’ milestones. While the general outline remained the same (strategy, design, development, launch) there was a lot more overlap with how tasks informed each other, and would keep informing and re-informing as an iterative workflow would encourage. Trying to fit a very fluid process into my very stiff linear approach to project planning didn’t work so well. I didn’t have the right strategies to manage risks in a productive way without feeling like the whole project was off track; with the habit of account for granular details all the time, I struggled to lean on others to help define what we should work on and when, and being okay if that changed once, or twice, or three times. Everything I learned about the process of product development came from learning on the job and making a ton of mistakes—and I knew I wanted to get better. Photo by Christin Hume on Unsplash I was fortunate enough to work with a group of developers who were looking to make a change, too. Being ‘agile’-enthusiasts, this group of developers were desperately looking for ways to infuse our approach to product work with agile-minded principles (the broad definition of ‘agile’ comes from ‘The Agile Manifesto’, which has influenced frameworks for organizing people and information, often applied in product development). This not only applied to how I worked with them, but how they worked with each other, and the way we all onboarded clients to these new expectations. This was a huge eye opener to me. Soon enough, I started applying these agile strategies to my day-to-day— running stand-ups, setting up backlogs, and reorganizing the way I thought about work output. It’s from this experience that I decided it may be worth learning these principles more formally. The choice to get certified There is a lot of literature out there about agile methodologies and a lot to be learned from casual research. This benefitted me for a while until I started to work on more complicated projects, or projects with more ambitious feature requests. My decision to ultimately pursue a formal agile certification really came down to three things: An increased use of agile methods across my team. Within my day-to-day I would encounter more team members who were familiar with these tactics and wanted to use them to structure the projects they worked on.The need for a clear definition of what processes to follow. I needed to grasp a real understanding of how to implement agile processes and stay consistent with using them to be an effective champion of these principles.Being able to diversify my experience. Finding ways to differentiate my resume from others with similar experience would be an added benefit to getting a certification. If nothing else, it would demonstrate that I’m curious-minded and proactive about my career. To achieve these things, I gravitated towards a more foundational education in a specific agile-methodology. This made Scrum the most logical choice given it’s the basis for many of the agile strategies out there and its dominance in the field. Evaluating all the options For Scrum education and certification, there are really two major players to consider. Scrum Alliance - Probably the most well known Scrum organization is Scrum Alliance. They are a highly recognizable organization that does a lot to further the broader understanding of Scrum as a practice.Scrum.org - Led by the original co-founder of Scrum, Ken Schwaber, Scrum.org is well-respected and touted for its authority in the industry. Each has their own approach to teaching and awarding certifications as well as differences in price point and course style that are important to be aware of. SCRUM ALLIANCE Pros Strong name recognition and leaders in the Scrum fieldOffers both in-person and online coursesHosts in-person events, webinars, and global conferencesProvides robust amounts of educational resources for its membersHas specialization tracks for folks looking to apply Scrum to their specific disciplineMembers are required to keep their skills up to date by earning educational credits throughout the year to retain their certificationConsistent information across all course administrators ensuring you'll be set up to succeed when taking your certification test. Cons High cost creates a significant barrier to entry (we’re talking in the thousands of dollars here)Courses are required to take the certification testCertification expires after two years, requiring additional investment in time and/or money to retain credentialsDifficult to find sample course material ahead of committing to a courseCourses are several days long which may mean taking time away from a day job to complete them SCRUM.ORG Pros Strong clout due to its founder, Ken Schwaber, who is the originator of ScrumOffers in-person classes and self-paced optionsHosts in-person events and meetups around the worldProvides free resources and materials to the public, including practice testsHas specialization tracks for folks looking to apply Scrum to their specific disciplineMinimum score on certification test required to pass; certification lasts for lifeLower cost for certification when compared to peers Cons Much lesser known to the general public, as compared to its counterpartLess sophisticated educational resources (mostly confined to PDFs or online forums) making digesting the material challengingPractice tests are slightly out of date making them less effective as a study toolSelf-paced education is not structured and therefore can’t ensure you’re learning everything you need to know for the testLack of active and engaging community will leave something to be desired Before coming to a decision, it was helpful to me to weigh these pros and cons against a set of criteria. Here’s a helpful scorecard I used to compare the two institutions. Scrum Alliance Scrum.org Affordability ⚪⚪⚪⚪ Rigor⚪⚪⚪⚪⚪ Reputation⚪⚪⚪⚪⚪ Recognition⚪⚪⚪⚪ Community⚪⚪⚪⚪ Access⚪⚪⚪⚪⚪ Flexibility⚪⚪⚪⚪ Specialization⚪⚪⚪⚪⚪⚪ Requirements⚪⚪⚪⚪ Longevity⚪⚪⚪⚪ For me, the four areas that were most important to me were: Affordability - I’d be self-funding this certificate so the investment of cost would need to be manageable.Self-paced - Not having a lot of time to devote in one sitting, the ability to chip away at coursework was appealing to me.Reputation - Having a certificate backed by a well-respected institution was important to me if I was going to put in the time to achieve this credential.Access - Because I wanted to be a champion for this framework for others in my organization, having access to resources and materials would help me do that more effectively. Ultimately, I decided upon a Professional Scrum Master certification from Scrum.org! The price and flexibility of learning course content were most important to me. I found a ton of free materials on Scrum.org that I could study myself and their practice tests gave me a good idea of how well I was progressing before I committed to the cost of actually taking the test. And, the pedigree of certification felt comparable to that of Scrum Alliance, especially considering that the founder of Scrum himself ran the organization. Putting a certificate to good use I don’t work in a formal Agile company, and not everyone I work with knows the ins and outs of Scrum. I didn’t use my certification to leverage a career change or new job title. So after all that time, money, and energy, was it worth it?I think so. I feel like I use my certification every day and employ many of the principles of Scrum in my day-to-day management of projects and people. Self-organizing teams is really important when fostering trust and collaboration among project members. This means leaning on each other’s past experiences and lessons learned to inform our own approach to work. It also means taking a step back as a project manager to recognize the strengths on your team and trust their lead.Approaching things in bite size pieces is also a best practice I use every day. Even when there isn't a mandated sprint rhythm, breaking things down into effort level, goals, and requirements is an excellent way to approach work confidently and avoid getting too overwhelmed.Retrospectives and stand ups are also absolute musts for Scrum practices, and these can be modified to work for companies and project teams of all shapes and sizes. Keeping a practice of collective communication and reflection will keep a team humming and provides a safe space to vent and improve. Photo by Gautam Lakum on Unsplash Parting advice I think furthering your understanding of industry standards and keeping yourself open to new ways of working will always benefit you as a professional. Professional certifications are readily available and may be more relevant than ever. If you’re on this path, good luck! And here are some things to consider: Do your research – With so many educational institutions out there, you can definitely find the right one for you, with the level of rigor you’re looking for.Look for company credits or incentives – some companies cover part or all of the cost for continuing education.Get started ASAP – You don’t need a full certification to start implementing small tactics to your workflows. Implementing learnings gradually will help you determine if it’s really something you want to pursue more formally. Full Article News & Culture Project Management
pr First impressions of the Fuji X-Pro2 (and the Fujinon 100-400mm lens) By feedproxy.google.com Published On :: Wed, 16 Mar 2016 20:16:47 +0000 Fuji released their new flagship camera this month, the X-Pro2. It is the first X-series camera to feature a 24MP sensor (compared to 16MP before) and it has a very interesting hybrid optical & electronic view finder. When I first […] Full Article Hardware Thoughts
pr Photography Life makes all their paid premium courses free By feedproxy.google.com Published On :: Fri, 08 May 2020 09:10:59 +0000 Photography Life has just contributed to the selection of online courses that you can take for free. While their premim courses are normally paid $150 per course, you can now access them free of charge. The founders have released them on YouTube, available for everyone to watch. The Photography Life team came to the decision […] The post Photography Life makes all their paid premium courses free appeared first on DIY Photography. Full Article news Course free class online courses Photography Life
pr Une promenade en forêt à Padoue By feedproxy.google.com Published On :: Fri, 06 Mar 2020 03:35:35 +0000 Padoue, Bas-St-Laurent, Québec Full Article Hiver Padoue Paysage foret hiver neige
pr Après les nuages, on retrouve toujours la lumière By feedproxy.google.com Published On :: Tue, 07 Apr 2020 22:39:57 +0000 St-Donat, Bas-St-Laurent, Québec Full Article aérienne Paysage St-Donat campagne lumière rural
pr Printemps à la campagne By feedproxy.google.com Published On :: Sun, 19 Apr 2020 23:27:21 +0000 St-Donat, Bas-St-Laurent, Québec Full Article Paysage Printemps St-Donat campagne champs fonte
pr Surprise… un peu de neige dans les arbres By feedproxy.google.com Published On :: Mon, 20 Apr 2020 23:18:32 +0000 St-Donat, Bas-St-Laurent, Québec Full Article aérienne Paysage Printemps St-Donat mont printemps route
pr Un beau matin de printemps By feedproxy.google.com Published On :: Thu, 07 May 2020 23:23:09 +0000 St-Donat, Bas-St-Laurent, Québec Full Article aérienne Paysage Printemps St-Donat printemps rural village
pr Un peu après le coucher du soleil By feedproxy.google.com Published On :: Fri, 08 May 2020 23:04:54 +0000 St-Donat, Bas-St-Laurent, Québec Full Article aérienne Paysage Printemps St-Donat ciel soir village
pr Paper: Evidence for Area as the Primary Visual Cue in Pie Charts By eagereyes.org Published On :: Thu, 17 Oct 2019 15:52:12 +0000 How we read pie charts is still an open question: is it angle? Is it area? Is it arc length? In a study I'm presenting as a short paper at the IEEE VIS conference in Vancouver next week, I tried to tease the visual cues apart – using modeling and 3D pie charts. The big […] Full Article Blog 2019 paper pie charts
pr Prolific, the (Much Better) Mechnical Turk Alternative By eagereyes.org Published On :: Tue, 05 Nov 2019 07:17:08 +0000 Prolific is a crowd-sourcing platform for running studies. In contrast to the widely-used Mechanical Turk, it’s specific to studies, has a much better interface, pricing that’s fair to participants, and useful filters to find the right people for your study. Amazon's Mechanical Turk is used for many empirical studies published in the visualization literature, but […] Full Article Blog 2019
pr ISOTYPE Book: Young, Prager, There’s Work for All By eagereyes.org Published On :: Mon, 02 Dec 2019 01:54:26 +0000 This book from 1945 contains a very interesting mix of different charts made by the ISOTYPE Institute, some classic and some quite unusual. As a book about labor and unemployment, it also makes extensive use of Gerd Arntz’s famous unemployed man icon. Michael Young and Theodor Prager’s There’s Work for All is part of a […] Full Article ISOTYPE Books isotype
pr In Praise of the Diagonal Reference Line By eagereyes.org Published On :: Tue, 24 Mar 2020 05:51:19 +0000 Annotations are what set visual communication and journalism apart from just visualization. They often consist of text, but some of the most useful annotations are graphical elements, and many of them are very simple. One type I have a particular fondness for is the diagonal reference line, which has been used to provide powerful context […] Full Article Blog 2020 COVID-19 Visual Communication
pr Nonlinear singular problems with indefinite potential term. (arXiv:2005.01789v3 [math.AP] UPDATED) By arxiv.org Published On :: We consider a nonlinear Dirichlet problem driven by a nonhomogeneous differential operator plus an indefinite potential. In the reaction we have the competing effects of a singular term and of concave and convex nonlinearities. In this paper the concave term is parametric. We prove a bifurcation-type theorem describing the changes in the set of positive solutions as the positive parameter $lambda$ varies. This work continues our research published in arXiv:2004.12583, where $xi equiv 0 $ and in the reaction the parametric term is the singular one. Full Article
pr Approximate Two-Sphere One-Cylinder Inequality in Parabolic Periodic Homogenization. (arXiv:2005.00989v2 [math.AP] UPDATED) By arxiv.org Published On :: In this paper, for a family of second-order parabolic equation with rapidly oscillating and time-dependent periodic coefficients, we are interested in an approximate two-sphere one-cylinder inequality for these solutions in parabolic periodic homogenization, which implies an approximate quantitative propagation of smallness. The proof relies on the asymptotic behavior of fundamental solutions and the Lagrange interpolation technique. Full Article
pr Solving an inverse problem for the Sturm-Liouville operator with a singular potential by Yurko's method. (arXiv:2004.14721v2 [math.SP] UPDATED) By arxiv.org Published On :: An inverse spectral problem for the Sturm-Liouville operator with a singular potential from the class $W_2^{-1}$ is solved by the method of spectral mappings. We prove the uniqueness theorem, develop a constructive algorithm for solution, and obtain necessary and sufficient conditions of solvability for the inverse problem in the self-adjoint and the non-self-adjoint cases Full Article
pr On the exterior Dirichlet problem for a class of fully nonlinear elliptic equations. (arXiv:2004.12660v3 [math.AP] UPDATED) By arxiv.org Published On :: In this paper, we mainly establish the existence and uniqueness theorem for solutions of the exterior Dirichlet problem for a class of fully nonlinear second-order elliptic equations related to the eigenvalues of the Hessian, with prescribed generalized symmetric asymptotic behavior at infinity. Moreover, we give some new results for the Hessian equations, Hessian quotient equations and the special Lagrangian equations, which have been studied previously. Full Article
pr Differentiating through Log-Log Convex Programs. (arXiv:2004.12553v2 [math.OC] UPDATED) By arxiv.org Published On :: We show how to efficiently compute the derivative (when it exists) of the solution map of log-log convex programs (LLCPs). These are nonconvex, nonsmooth optimization problems with positive variables that become convex when the variables, objective functions, and constraint functions are replaced with their logs. We focus specifically on LLCPs generated by disciplined geometric programming, a grammar consisting of a set of atomic functions with known log-log curvature and a composition rule for combining them. We represent a parametrized LLCP as the composition of a smooth transformation of parameters, a convex optimization problem, and an exponential transformation of the convex optimization problem's solution. The derivative of this composition can be computed efficiently, using recently developed methods for differentiating through convex optimization problems. We implement our method in CVXPY, a Python-embedded modeling language and rewriting system for convex optimization. In just a few lines of code, a user can specify a parametrized LLCP, solve it, and evaluate the derivative or its adjoint at a vector. This makes it possible to conduct sensitivity analyses of solutions, given perturbations to the parameters, and to compute the gradient of a function of the solution with respect to the parameters. We use the adjoint of the derivative to implement differentiable log-log convex optimization layers in PyTorch and TensorFlow. Finally, we present applications to designing queuing systems and fitting structured prediction models. Full Article
pr Equivalence of classical and quantum completeness for real principal type operators on the circle. (arXiv:2004.07547v3 [math.AP] UPDATED) By arxiv.org Published On :: In this article, we prove that the completeness of the Hamilton flow and essential self-dajointness are equivalent for real principal type operators on the circle. Moreover, we study spectral properties of these operators. Full Article
pr On the Asymptotic $u_0$-Expected Flooding Time of Stationary Edge-Markovian Graphs. (arXiv:2004.03660v4 [math.PR] UPDATED) By arxiv.org Published On :: Consider that $u_0$ nodes are aware of some piece of data $d_0$. This note derives the expected time required for the data $d_0$ to be disseminated through-out a network of $n$ nodes, when communication between nodes evolves according to a graphical Markov model $overline{ mathcal{G}}_{n,hat{p}}$ with probability parameter $hat{p}$. In this model, an edge between two nodes exists at discrete time $k in mathbb{N}^+$ with probability $hat{p}$ if this edge existed at $k-1$, and with probability $(1-hat{p})$ if this edge did not exist at $k-1$. Each edge is interpreted as a bidirectional communication link over which data between neighbors is shared. The initial communication graph is assumed to be an Erdos-Renyi random graph with parameters $(n,hat{p})$, hence we consider a emph{stationary} Markov model $overline{mathcal{G}}_{n,hat{p}}$. The asymptotic "$u_0$-expected flooding time" of $overline{mathcal{G}}_{n,hat{p}}$ is defined as the expected number of iterations required to transmit the data $d_0$ from $u_0$ nodes to $n$ nodes, in the limit as $n$ approaches infinity. Although most previous results on the asymptotic flooding time in graphical Markov models are either emph{almost sure} or emph{with high probability}, the bounds obtained here are emph{in expectation}. However, our bounds are tighter and can be more complete than previous results. Full Article
pr $L^p$-regularity of the Bergman projection on quotient domains. (arXiv:2004.02598v2 [math.CV] UPDATED) By arxiv.org Published On :: We relate the $L^p$-mapping properties of the Bergman projections on two domains in $mathbb{C}^n$, one of which is the quotient of the other under the action of a finite group of biholomorphic automorphisms. We use this relation to deduce the sharp ranges of $L^p$-boundedness of the Bergman projection on certain $n$-dimensional model domains generalizing the Hartogs triangle. Full Article
pr Set-Theoretical Problems in Asymptology. (arXiv:2004.01979v3 [math.GN] UPDATED) By arxiv.org Published On :: In this paper we collect some open set-theoretic problems that appear in the large-scale topology (called also Asymptology). In particular we ask problems about critical cardinalities of some special (large, indiscrete, inseparated) coarse structures on $omega$, about the interplay between properties of a coarse space and its Higson corona, about some special ultrafilters ($T$-points and cellular $T$-points) related to finitary coarse structures on $omega$, about partitions of coarse spaces into thin pieces, and also about coarse groups having some extremal properties. Full Article
pr A stochastic approach to the synchronization of coupled oscillators. (arXiv:2002.04472v2 [nlin.AO] UPDATED) By arxiv.org Published On :: This paper deals with an optimal control problem associated to the Kuramoto model describing the dynamical behavior of a network of coupled oscillators. Our aim is to design a suitable control function allowing us to steer the system to a synchronized configuration in which all the oscillators are aligned on the same phase. This control is computed via the minimization of a given cost functional associated with the dynamics considered. For this minimization, we propose a novel approach based on the combination of a standard Gradient Descent (GD) methodology with the recently-developed Random Batch Method (RBM) for the efficient numerical approximation of collective dynamics. Our simulations show that the employment of RBM improves the performances of the GD algorithm, reducing the computational complexity of the minimization process and allowing for a more efficient control calculation. Full Article
pr Stationary Gaussian Free Fields Coupled with Stochastic Log-Gases via Multiple SLEs. (arXiv:2001.03079v3 [math.PR] UPDATED) By arxiv.org Published On :: Miller and Sheffield introduced a notion of an imaginary surface as an equivalence class of pairs of simply connected proper subdomains of $mathbb{C}$ and Gaussian free fields (GFFs) on them under conformal equivalence. They considered the situation in which the conformal transformations are given by a chordal Schramm--Loewner evolution (SLE). In the present paper, we construct processes of GFF on $mathbb{H}$ (the upper half-plane) and $mathbb{O}$ (the first orthant of $mathbb{C}$) by coupling zero-boundary GFFs on these domains with stochastic log-gases defined on parts of boundaries of the domains, $mathbb{R}$ and $mathbb{R}_+$, called the Dyson model and the Bru--Wishart process, respectively, using multiple SLEs evolving in time. We prove that the obtained processes of GFF are stationary. The stationarity defines an equivalence relation between GFFs, and the pairs of time-evolutionary domains and stationary processes of GFF will be regarded as generalizations of the imaginary surfaces studied by Miller and Sheffield. Full Article
pr Linear Convergence of First- and Zeroth-Order Primal-Dual Algorithms for Distributed Nonconvex Optimization. (arXiv:1912.12110v2 [math.OC] UPDATED) By arxiv.org Published On :: This paper considers the distributed nonconvex optimization problem of minimizing a global cost function formed by a sum of local cost functions by using local information exchange. We first propose a distributed first-order primal-dual algorithm. We show that it converges sublinearly to the stationary point if each local cost function is smooth and linearly to the global optimum under an additional condition that the global cost function satisfies the Polyak-{L}ojasiewicz condition. This condition is weaker than strong convexity, which is a standard condition for proving the linear convergence of distributed optimization algorithms, and the global minimizer is not necessarily unique or finite. Motivated by the situations where the gradients are unavailable, we then propose a distributed zeroth-order algorithm, derived from the proposed distributed first-order algorithm by using a deterministic gradient estimator, and show that it has the same convergence properties as the proposed first-order algorithm under the same conditions. The theoretical results are illustrated by numerical simulations. Full Article
pr Regularized vortex approximation for 2D Euler equations with transport noise. (arXiv:1912.07233v2 [math.PR] UPDATED) By arxiv.org Published On :: We study a mean field approximation for the 2D Euler vorticity equation driven by a transport noise. We prove that the Euler equations can be approximated by interacting point vortices driven by a regularized Biot-Savart kernel and the same common noise. The approximation happens by sending the number of particles $N$ to infinity and the regularization $epsilon$ in the Biot-Savart kernel to $0$, as a suitable function of $N$. Full Article
pr Multitype branching process with nonhomogeneous Poisson and generalized Polya immigration. (arXiv:1909.03684v2 [math.PR] UPDATED) By arxiv.org Published On :: In a multitype branching process, it is assumed that immigrants arrive according to a nonhomogeneous Poisson or a generalized Polya process (both processes are formulated as a nonhomogeneous birth process with an appropriate choice of transition intensities). We show that the renormalized numbers of objects of the various types alive at time $t$ for supercritical, critical, and subcritical cases jointly converge in distribution under those two different arrival processes. Furthermore, some transient moment analysis when there are only two types of particles is provided. AMS 2000 subject classifications: Primary 60J80, 60J85; secondary 60K10, 60K25, 90B15. Full Article
pr Infinite dimensional affine processes. (arXiv:1907.10337v3 [math.PR] UPDATED) By arxiv.org Published On :: The goal of this article is to investigate infinite dimensional affine diffusion processes on the canonical state space. This includes a derivation of the corresponding system of Riccati differential equations and an existence proof for such processes, which has been missing in the literature so far. For the existence proof, we will regard affine processes as solutions to infinite dimensional stochastic differential equations with values in Hilbert spaces. This requires a suitable version of the Yamada-Watanabe theorem, which we will provide in this paper. Several examples of infinite dimensional affine processes accompany our results. Full Article
pr Representations of the Infinite-Dimensional $p$-Adic Affine Group. (arXiv:1906.08964v2 [math.RT] UPDATED) By arxiv.org Published On :: We introduce an infinite-dimensional $p$-adic affine group and construct its irreducible unitary representation. Our approach follows the one used by Vershik, Gelfand and Graev for the diffeomorphism group, but with modifications made necessary by the fact that the group does not act on the phase space. However it is possible to define its action on some classes of functions. Full Article
pr Decentralized and Parallelized Primal and Dual Accelerated Methods for Stochastic Convex Programming Problems. (arXiv:1904.09015v10 [math.OC] UPDATED) By arxiv.org Published On :: We introduce primal and dual stochastic gradient oracle methods for decentralized convex optimization problems. Both for primal and dual oracles the proposed methods are optimal in terms of the number of communication steps. However, for all classes of the objective, the optimality in terms of the number of oracle calls per node in the class of methods with optimal number of communication steps takes place only up to a logarithmic factor and the notion of smoothness. By using mini-batching technique we show that all proposed methods with stochastic oracle can be additionally parallelized at each node. Full Article
pr Grothendieck's inequalities for JB$^*$-triples: Proof of the Barton-Friedman conjecture. (arXiv:1903.08931v3 [math.OA] UPDATED) By arxiv.org Published On :: We prove that, given a constant $K> 2$ and a bounded linear operator $T$ from a JB$^*$-triple $E$ into a complex Hilbert space $H$, there exists a norm-one functional $psiin E^*$ satisfying $$|T(x)| leq K , |T| , |x|_{psi},$$ for all $xin E$. Applying this result we show that, given $G > 8 (1+2sqrt{3})$ and a bounded bilinear form $V$ on the Cartesian product of two JB$^*$-triples $E$ and $B$, there exist norm-one functionals $varphiin E^{*}$ and $psiin B^{*}$ satisfying $$|V(x,y)| leq G |V| , |x|_{varphi} , |y|_{psi}$$ for all $(x,y)in E imes B$. These results prove a conjecture pursued during almost twenty years. Full Article
pr Gabriel-Roiter measure, representation dimension and rejective chains. (arXiv:1903.05555v2 [math.RT] UPDATED) By arxiv.org Published On :: The Gabriel-Roiter measure is used to give an alternative proof of the finiteness of the representation dimension for Artin algebras, a result established by Iyama in 2002. The concept of Gabriel-Roiter measure can be extended to abelian length categories and every such category has multiple Gabriel-Roiter measures. Using this notion, we prove the following broader statement: given any object $X$ and any Gabriel-Roiter measure $mu$ in an abelian length category $mathcal{A}$, there exists an object $X'$ which depends on $X$ and $mu$, such that $Gamma = operatorname{End}_{mathcal{A}}(X oplus X')$ has finite global dimension. Analogously to Iyama's original results, our construction yields quasihereditary rings and fits into the theory of rejective chains. Full Article
pr Optimal construction of Koopman eigenfunctions for prediction and control. (arXiv:1810.08733v3 [math.OC] UPDATED) By arxiv.org Published On :: This work presents a novel data-driven framework for constructing eigenfunctions of the Koopman operator geared toward prediction and control. The method leverages the richness of the spectrum of the Koopman operator away from attractors to construct a rich set of eigenfunctions such that the state (or any other observable quantity of interest) is in the span of these eigenfunctions and hence predictable in a linear fashion. The eigenfunction construction is optimization-based with no dictionary selection required. Once a predictor for the uncontrolled part of the system is obtained in this way, the incorporation of control is done through a multi-step prediction error minimization, carried out by a simple linear least-squares regression. The predictor so obtained is in the form of a linear controlled dynamical system and can be readily applied within the Koopman model predictive control framework of [12] to control nonlinear dynamical systems using linear model predictive control tools. The method is entirely data-driven and based purely on convex optimization, with no reliance on neural networks or other non-convex machine learning tools. The novel eigenfunction construction method is also analyzed theoretically, proving rigorously that the family of eigenfunctions obtained is rich enough to span the space of all continuous functions. In addition, the method is extended to construct generalized eigenfunctions that also give rise Koopman invariant subspaces and hence can be used for linear prediction. Detailed numerical examples with code available online demonstrate the approach, both for prediction and feedback control. Full Article
pr 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