![]() ![]() Generally, thick bars have good torque and are efficient at low slip, since they present lower resistance to the EMF. Rotors for three-phase will have variations in the depth and shape of bars to suit the design classification. The same basic design is used for both single-phase and three-phase motors over a wide range of sizes. The material is a low carbon but high- silicon iron with several times the resistivity of pure iron, further reducing eddy-current loss, and low coercivity to reduce hysteresis loss. It is made of thin laminations, separated by varnish insulation, to reduce eddy currents circulating in the core. Because the magnetic field in the rotor is alternating with time, the core uses construction similar to a transformer core to reduce core energy losses. The iron core serves to carry the magnetic field through the rotor conductors. The constructions that offer the least feedback use prime numbers of rotor bars. ![]() The number of bars in the rotor determines to what extent the induced currents are fed back to the stator coils and hence the current through them. The greatest common divisor of 36 and 40 is 4, with the result that no more than 4 bars of the stator and rotor can be aligned at any one time, which also reduces torque fluctuations. The laminations shown in the photo have 36 bars in the stator and 40 bars in the rotor. If rotor bars were parallel to the stator poles, the motor would experience a drop and then recovery in torque as each bar passes the gap in the stator. The conductors are often skewed slightly along the length of the rotor to reduce noise and smooth out torque fluctuations that might result at some speeds due to interactions with the pole pieces of the stator, by ensuring that at any time the same fraction of a rotor bar is under each stator slot. The difference in speed is called slip and increases with load. In effect the rotor is carried around with the magnetic field but at a slightly slower rate of rotation. In turn these currents lengthwise in the conductors react with the magnetic field of the motor to produce force acting at a tangent orthogonal to the rotor, resulting in torque to turn the shaft. The relative motion between this field and the rotor induces electric current in the conductive bars. The field windings in the stator of an induction motor set up a rotating magnetic field through the rotor. Since the voltage developed in the squirrel cage winding is very low, and the current very high, no intentional insulation layer is present between the bars and the rotor steel. Larger motors have aluminium or copper bars which are welded or brazed to end-rings. A very common structure for smaller motors uses die cast aluminium poured into the rotor after the laminations are stacked. The rotor bars may be made of either copper or aluminium. Laminations, with 36 slots for the stator and 40 slots for the rotor By the end of the 19th century induction motors were widely applied on the growing alternating-current electrical distributions systems. In 1889, Mikhail Dolivo-Dobrovolsky developed a wound-rotor induction motor, and shortly afterwards a cage-type rotor winding. Developments of this design became commercially important. In 1888, Nikola Tesla received a patent on a two-phase induction motor with a short-circuited copper rotor winding and a two-phase stator winding. Galileo Ferraris described an induction machine with a two-phase stator winding and a solid copper cylindrical armature in 1885. This simplifies application and replacement of these motors. ![]() Commonly used motors in industry are usually IEC or NEMA standard frame sizes, which are interchangeable between manufacturers. They are simple, rugged, and self-starting, and maintain a reasonably constant speed from light load to full load, set by the frequency of the power supply and the number of poles of the stator winding. Squirrel-cage induction motors are very prevalent in industry, in sizes from below 1 kilowatt (1.3 hp) up to tens of megawatts (tens-of-thousand horsepower). The interaction of the magnetic fields of currents in the stator and rotor produce a torque on the rotor.īy adjusting the shape of the bars in the rotor, the speed-torque characteristics of the motor can be changed, to minimize starting current or to maximize low-speed torque, for example. The rotor winding has current induced in it by the stator field, like a transformer except that the current in the rotor is varying at the stator field rotation rate minus the physical rotation rate. In operation, the non-rotating stator winding is connected to an alternating current power source the alternating current in the stator produces a rotating magnetic field. It consists of a cylinder of steel laminations, with aluminum or copper conductors embedded in its surface. A squirrel-cage rotor is the rotating part of the common squirrel-cage induction motor. ![]()
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![]() ![]() Because of the added complexities of the refugee and immigrant context, a deep understanding of their realities is needed. My advice would be to keep key guidance artifacts (such as project objectives, product roadmap, solution architecture) high level, lightweight and visual, and stick them on the wall along with the team’s User Stories and daily tasks.Providing contextually appropriate care and interventions for people with diabetes and/or obesity in vulnerable situations within ethnocultural newcomer communities presents significant challenges. So, in summary, an agile development team might break things into small pieces and deliver incrementally, but this makes it even more important to have the overall context always in mind. In my view, this can be an evolving picture, the kind of thing that is sketched on a whiteboard at the start of the project, with more details being filled in as the project progresses and as technical decisions are taken. High-level Solution Architecture – this doesn’t need to be a detailed design, but you do need some architectural guidance in order to understand key technologies, product structure and how the overall solution hangs together from a technical perspective.But it’s a guide to what’s intended at the outset, and should cover the main scenarios for an everyday user. And the solution may not look exactly like the visuals when it’s finished. The visuals don’t need to cover every single screen. Whatever form it takes, it’s a high level outline of how the solution will hang together from a user’s perspective. High-level Visuals – this could be wireframes for key screens, Creative visuals of a web site, a conceptual story board for the UI (User Interface), etc.This provides the team with some structure around Sprint Planning, with the Product Roadmap helping to inform the priorities of each Sprint and set Sprint Goals. Unlike a plan, a Product Roadmap is indicative and evolves as things change. High-level Product Roadmap – broad timeline across the top, perhaps in months or quarters highlighting key product features or milestones.So what artifacts help us to do this? There may be others, but here are some things I certainly like to see before getting down to User Stories on a Sprint-by-Sprint basis: It is important to look at individual User Stories in context of the overall solution. But what should you do before you get down to the detail of individual User Stories? I’ve written quite a few entries on my blog about them recently, and how to write good User Stories. With this guidance, the project team has some parameters to work within, and a clear understanding of the expected outcomes. And that guidance is more important than ever in an agile development approach, because of the freedom to change things along the way. The answers to these questions (and more, of course) give people important guidance. What is the specific problem or opportunity that the project is seeking to address? What is the vision for the project? What are the project objectives? What is the scope (broadly speaking)? What is the likely cost and timeframe? What are the benefits and how will they be realised? Who will work on the project and what is the project structure? If the development team is working on a project, many of the things defined in a more traditional project initiation phase are just as important in an agile development environment. Without necessarily being asked to work on a problem, or without being asked to come up with an idea, solutions to problems and new innovations will come to mind. With this information – if development teams have a real insight into the business context – people on the development team can be proactive. In my experience, development people can be quite innovative. Without this over-arching contextual information, any product development team is working with a major disadvantage. What is the business vision? What are the challenges and opportunities from a business point of view? What are the business goals – short, medium and longer term? Who are the customers? Why do they buy, and what do they use the solution for? What do they like and dislike about the product? Who is the competition and what are their solutions like? So, with this moving target, how do you keep sight of the bigger picture?Īlthough agile development is all about breaking things down – breaking things down into micro pieces and delivering on a piecemeal basis – it is also very important to have some overall guiding context.įrom my perspective, this context comes in 3 major forms: ![]() Features can be added, changed and removed throughout the project lifecycle. With an agile development approach, there is no big spec and no big design up-front. ![]() ![]() ![]() ![]() The game that got me to buy the system is also what I think is the system's best game. The 'Cube was a fun system to experience in its time. That's why the HD port was so disappointing with a little love and attention it could have been the best Tales game, instead it comes across as lazy. Xillia for example recycles a lot of Symphonias plot points but the accompanying story is so convuluted and needlessly dense that you very quickly tune out. It's a really effectively told story, especially compared to some of the more recent games. I'd actually argue it's one of the best storys in the Tales franchise the way they subtly show the effects of racism in its varying forms, as opposed to battering you over the head with dialogue about it, means that by the time you meet the overall 'villain' you completely understand his motives. Was pleasantly surprised by the Zelda collectors and Master Quest ranking so high though.Īlso, regarding Tales of Symphona "although the plot might be a little workaday if you're at all familiar with the genre, there's a lot to love here". There are a lot of games lower down that I was initially annoyed by them being so low, but when you consider just how many truly quality games the GC had it's inevitable that some will get pushed lower than seems fair (though it always pains me how disregarded Sunshine is, and the lack of Pokémon Colosseum is a real oddity imo). However, unlike other static lists, this one constantly evolves to reflect ratings from Nintendo Life users, so you can still participate. The ranking is formed entirely from each game's user rating in the Nintendo Life Games database. We asked Nintendo Life readers to rate their favourite GameCube games, and the result is the list of 50 games you see below. This was the last time Nintendo put itself in direct competition with Sony and Microsoft in pure spec terms before changing tack with the Wii. Its striking indigo colour, big chunky 'A' button, cute little discs, and infamous carry handle ultimately worked against it in an era of sleek, all-in-one multimedia machines, but it was a powerful little box of tricks that played host to a fabulous library of games. Image: Zion Grassl / Nintendo LifeĮschewing the jack-of-all-trades direction of its contemporaries, the console concentrated on doing just one thing well: playing games. The NGC (sorry, GCN) is a beautiful, compact piece of kit. Unlucky Europeans wouldn't get their hands on it until the following year, but the wait was worth it for one of the best-looking video game consoles of all time. The Nintendo GameCube launched in Japan in September 2001 and a couple of months later on 18th November in North America. ![]() ![]() There are other good scanner apps out there, but this is by far the best photo scanner app I have ever used. Not sure if it is user error but recommend Google tech developers get on that! It was getting stuck in the export of the data from my iPhone. I find that the Google Photos app doesn’t want to work well with my MacBook Pro. Only issue of mine is the lack of real seamless syncing with my MacBook Pro. I would highly recommend everyone use this app to scan old photos of family members, pets, or anything you cherish and want kept for posterity. Works pretty darn well and am impressed how true to the actual pictures the digital copy chame out. Nonetheless, I thought to myself with all the recent advances in technology isn’t their an easier way to scan these photos for posterity as well as use for a slideshow tribute? Yes, indeed there was and it was free of charge from Google. We were using an Epson scanner and found it very tedious and time-,consuming despite the obvious grief we were experiencing for his recent passing. I was assisting my wife scan the numerous photos of her father throughout his life. I was turned onto this app when my father-in-law recently passed away. I love how intuitive the app was to digitally scan old photos of family members. And share them with anyone, just by sending a link.Īwesome Digital Photo Scanner with iPhone Bring your scans to life with movies, filters, and advanced editing controls. – Smart rotation, so your photos stay right-side-up no matter which way you scan themĬapture your favorite printed photos quickly and easily, so you can spend less time editing and more time looking at your bad childhood haircut.įor documents and photos in glare-free environments, toggle off glare removal for even faster scans.īack up your scans with the Google Photos app to keep them safe, searchable, and organized. ![]() – Straight, rectangular scans with perspective correction – Automatic cropping based on edge detection – Get glare-free scans with an easy step-by-step capture flow ![]() Create enhanced digital scans, wherever your photos are. PhotoScan is an app from Google Photos that lets you scan and save your favorite printed photos using your phone’s camera.ĭon’t just take a picture of a picture. ![]() Photos from the past, meet scanner from the future. ![]() ![]() ![]() “It’s good for athletes to do something else,” VanBaak said. But they should avoid the same repetitive movements they performed during training or an event. Fresh blood flow then delivers nutrients that help repair and rebuild muscles, tendons, and ligaments.ĭuring active recovery, athletes should engage in light physical activity that raises the heart rate above a resting rate. Karin VanBaak discusses the importance of rest and recovery for all athletes.Īctive recovery increases blood circulation, which helps remove waste products from soft tissue that have been broken down by intense exercise. “So if I go out for a six-mile run in the morning, what do I do afterward to make sure that my body and mind can recover from that single bout of exercise?” Dr. “I tend to think of short-term recovery as what you are doing that day,” VanBaak said. Research shows that low-intensity exercise during the cool-down phase of your workout is associated with performance benefits. Short-term or active recovery occurs in the hours soon after intense exercise. “If you’re an athlete, it means taking time out from your usual sport.” Athletic trainers talk about two types of recovery: short-term or active recovery and long-term recovery. “In order to see gains in fitness, in order for the body to keep doing what you want it to do, you have to give it enough rest to repair itself,” VanBaak said. ![]() It’s important to remember that this process occurs during rest and recovery, not during the exercise session itself. Over time, as muscles heal, they eventually grow bigger and stronger. You’re taxing yourself and pushing yourself beyond your current level of fitness.”Įxercise – especially intense exercise – creates tiny tears in the muscles. “if you’re participating in sports, you’re breaking down your body. “The nuances are going to be a little bit different for everyone depending on their age, sport, and level of participation and development.”īut there’s one general principle that applies to all athletes, she said. “There’s not a one-size-fits-all answer about what it means for an athlete,” VanBaak said. What is meant by rest and recovery and why is it important? Karin VanBaak of the CU Sports Medicine & Performance Center, UCHealth Family Medicine – Boulder, and assistant professor in the Department of Family Medicine and Department of Orthopedics at the University of Colorado Anschutz Medical Campus explains why rest and recovery are critical for an athlete’s physiological and psychological well-being. Nobody questions the value of exercise training for optimal athletic performance and improvement.īut rest and recovery is an equally essential component of an exercise program because it gives the body time to repair, rebuild, and strengthen itself between workouts.ĭr. ![]() Rest and recovery are critical for an athlete’s physiological and psychological well-being. ![]() ![]() ![]() Program for students to support their Social and Emotional development.Ongoing assessment and evaluation are in a place to ensure high levels of accountability for all.This level of pay equity is matched by opportunities for professional development. Teachers at LEAP STEAM+E are valued and supported and our school compensates our teachers at the highest salary in Puerto Rico with teachers making twice as much as other public-school teachers in Puerto Rico.Families have opportunities for learning through access to Social and Emotional services, training and job readiness training. The school focuses on building solid and positive relationships with parents and community members and the school ensures that they have access to quality teachers and staff.Students will attend classes at Sagrado Corazon University. LEAP STEAM + E students participate in Early College beginning in grade 10 to ensure that they earn dual college credits and graduate already ahead as they begin their college careers.Students receive a computer to use at the school and at home when engaging in virtual learning opportunities.A focus on applied learning through an integrated curriculum that capitalizes on project-based learning and access to a Fabrication Lab so students can apply skills and learn by inventing and experimenting.Small Classroom sizes (20 students per classroom) to ensure that students are given individualized attention and that instructional routines are better organized.School opens at 7:00 am and is serving students through 6:00 pm every day. Extended Day and Year to ensure that students are taking advantage of every opportunity to learn and prepare.LEAP STEAM + E Academy features many innovative programs all geared at providing its students with the best quality of education, including: The academic focus for the school is STEAM (Science, Technology, Engineering, Arts, and Mathematics) with integration of entrepreneurship skills (+E), as the school channels its resources and priorities toward preparing students to develop the motivation and academic competencies to be competitive to enter the university and the labor force. That commitment and access along with the LEAP college culture raises achievement expectations for all of our students and builds hope and acts as a springboard to action. The innovative spirit of LEAP STEAM + E Academy of San Juan is reflected in its transformational approach to college readiness and access, and its commitment to serving all children. With a firm belief that quality education transforms lives, LEAP is an educational enterprise that is entrepreneurial, innovative, efficient and accountable. ![]() LEAP is focused on transforming educational opportunities for parents and children. The LEAP STEAM + E Academy of San Juan is the largest Alianza School in Puerto Rico, serving 600 students in grades K-9 and expanding to 720 when its student cohorts reach 12th grade. Empowering Educational Excellence & Community Development. ![]() |