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New method analyzes corn kernel characteristics

first_imgShare Facebook Twitter Google + LinkedIn Pinterest An ear of corn averages about 800 kernels. A traditional field method to estimate the number of kernels on the ear is to manually count the number of rows and multiply by the number of kernels in one length of the ear. With the help of a new imaging machine developed at the University of Illinois breeders can learn the number of kernels per ear, plus a lot more information than can be manually observed.“If you take that same ear of corn into a lab, you can take the same approach but use an imaging system to get a more accurate measure of the total number of kernels,” said Tony Grift, lead scientist on the project. “But you can go a lot further than that. By pinning the ear on a spike and turning it automatically, we can present each row individually to a camera. This allows us to determine up to 16 morphological characteristics of each kernel, including kernel area, circumference, and circularity, a measure for how close the kernel shape is to a circle. We can also calculate the center of gravity and the location of the kernel on the ear, in fact we use these to make sure we don’t count kernels more than once.”The imaging machine itself isn’t fancy. It’s more like a tabletop photography studio. A single halogen light is hung outside, above the box. The box itself is made from high-density polyethylene or HDPE, which is typically used to make cutting boards. This plastic adheres to virtually nothing (which is ideal for cutting boards) including glue, so it was assembled with bolts and fasteners.Grift says the key is in the lighting.“Having a good camera is one thing, but light is very important. Light has to come from everywhere, so we channel light from the halogen bulb through a thin layer of the same HDPE material, which reflects off the side walls in which the cameras were mounted as well. Using the box is simple: You open the door, put the ear of corn on the spike, close the door, and a motor automatically rotates the ear as many times as needed to capture all rows. The motor and two cameras inside are controlled by a computer program that records the information.”Grift says he’s been working with U of I maize breeder Martin Bohn since 2002 on perfecting imaging boxes.“We began working with roots, we called the box the Corn Root Imaging Box or CRIB,” Grift said. “Corn roots have an awkward shape which is difficult to capture. But we can calculate the stalk diameter, the root angle, and the fractal dimension, which is a way to describe a root’s complexity.”He says that at some point, he and his colleague Abdul Momin realized that they could put anything inside the box and decided to experiment with an ear of corn.Because an ear of corn is a natural object, the variations can make it difficult to image accurately.“It’s easier with ears that have very ‘well-behaved’ rows of kernels,” Grift said. “The rows on some ears of corn begin to spiral a bit, making it difficult to get an accurate reading without duplicating some kernels. Former students Wei Zhao and Yu Zhang made adjustments to allow for missing kernels, dead kernels, or some that were squeezed together or twisted, but overall, the imaging system works well.”“This is where it gets really interesting,” Grift said. “All of the measurements mean very little to us. I like to joke that we agricultural engineers are just glorified technicians on the project. We just provide the numbers in spread sheets. The spread sheet then goes to Martin Bohn who creates a QTL map — quantitative trait loci map — that associates the particular characteristics of the kernel with the genes that control them.”Martin Bohn, corn breeder and geneticist in the Department of Crop Sciences at U of I and co-author, notes that improved phenotyping methods, like the one this paper focuses on, are critical if we want to leverage genomic information in breeding and genetic research.“Most plant characteristics that determine the agronomic potential of plants are highly complex,” Bohn said. “For example, a large number of genes, mostly with small effects, contribute to traits farmers are interested in, such as yield, efficient uptake and use of nutrients, tolerance to drought, heat, cold, etc. We can only hope to find these important but small effect genes if we can measure plant traits efficiently and accurately for a large number of plants, hence the term high-throughput phenotyping. The method we report here does not only provide the technology to do exactly this, but it might also be possible to go beyond this. Imagine, being able to determine the nutritional content of each kernel on the cob using our approach. We would love to expand this idea and work with companies to move on from manual, tedious field measurements to smart imaging techniques.”The study, “Semi-automated, machine vision based maize kernel counting on the ear,” is published in Biosystems Engineering. The research was conducted by Tony Grift, Wei Zhao, Abdul Momin, Yu Zhang and Martin Bohn.last_img read more

KnowledgeTreeLive: Can Document Management Move to the Cloud?

first_imgIT + Project Management: A Love Affair steven walling Cognitive Automation is the Immediate Future of… Massive Non-Desk Workforce is an Opportunity fo… Tags:#enterprise center_img Related Posts Are you ready to move your documents in to the cloud? Knowledge Tree has released the new SaaS version of its document management software, dubbed KnowledgeTreeLive. Knowledge Tree is an open source commercial vendor, with both a community edition under the GPL and a proprietary enterprise version. The new subscription-based KnowledgeTreeLive is hosted on Amazon EC2. It has all the features of the on-premise version of the software, but also includes integration with the Zoho Office Suite for a fully cloud-based approach. An Enviable InterfaceIn terms of usability, KnowledgeTreeLive was on par with the self-hosted version, though unique to it is the integration with the Zoho Office Suite. What they both include is Microsoft Office support, and the main dashboard provides a useful, high-level overview of the system. The dashboard was made up of AJAX-y dashlets that can be added, removed and reordered in a drag-and-drop interface. Overall, the other vendor most comparable to this level of ease is Alfresco, which operates on a similar open source model. Bigger Up-front Cost is a KillerIt’s functionality might be superb, but there is something strange about KnowledgeTreeLive: it’s more expensive. According to the company’s price list on-premise version of Knowledge Tree has an annual fee of $2,400 for a 20-user license at the basic level. The most basic SaaS version is $2,950 for 10 users, and is limited to 50 GB of storage. For big enterprise, the lowered cost of IT would make up for the greater up-front subscription fee. But in a phone conversation, a Knowledge Tree spokesperson told ReadWriteWeb that the majority of those interested in the SaaS version were SMBs without strict compliance needs. For those companies, self-hosting the community edition could end up being both cheaper and more attuned to their needs. With lower costs being a primary driver of SaaS adoption overall, the relatively hefty subscription price could drive off the very customers that Knowledge Tree says are its core users for this edition. 3 Areas of Your Business that Need Tech Nowlast_img read more

Domestic Hot Water: No Perfect Solution

first_img Start Free Trial Already a member? Log in This article is only available to GBA Prime Members Sign up for a free trial and get instant access to this article as well as GBA’s complete library of premium articles and construction details.center_img Some questions are easier to answer than others. For example, there is a fairly straightforward answer to, “How should I insulate the floor of my unconditioned attic?” — namely, “With a deep layer of cellulose.” (There’s more to say on the topic, of course — but even a full answer isn’t very complicated.)There is no easy answer, however, to, “How should I heat my domestic hot water?” Every type of water heating technology is flawed; every solution involves compromise.Many factors affect the decision about what type of water heater to choose, including: The all-electric house If your house has an unshaded south-facing roof, or a generously sized yard with room for a ground-mounted PV array, it’s a good guess that your house will eventually be equipped with a solar electric system — especially if your local utility offers favorable net-metering contracts to customers with PV systems. Since PV costs keep dropping, it’s hard to imagine that PV won’t play a significant role in our energy future.As PV systems become increasingly common, energy experts predict that most U.S. homes will eventually be all-electric. Since burning fossil fuels contributes to global warming, environmentalists have been among the first to embrace the all-electric ideal.In many states, net-metering contracts wipe out a customer’s electricity credits at the end of the year. That means that PV system owners who produce more electricity than they use are forced to donate their extra electricity to the grid. Instead of giving their electricity away, homeowners with large PV systems often swap their gas-fired water heater for an electric water heater. After all, for anyone who is subject to a “use it or lose it” net-metering contract, it makes economic sense… last_img read more

10 Tips for Shooting Video on a White Seamless

first_imgRecreate the iconic look of the popular Apple product videos with these 10 tips!Shooting on a seamless white background is an incredibly popular way to draw attention to your subject while minimizing distractions. There are a number of different steps you can take to get this look, so we’ve compiled our 10 favorite tips for creating the popular Apple style look.This spoof on the Apple iWatch product video shows off this style.1. Use paper not a canvas.A common mistake among new photographers and videographers is to use a cloth canvas when trying to get the “seamless” look. Unfortunately cloth tends to crease up and it can be very difficult to get all the wrinkles out. Instead, try using a paper backdrop instead. Paper is much easier to keep wrinkle-free and it can be easily rolled back up and stored. You can pick up a 107 inch white paper roll for $45 at B&H.Photo from Ray Dobbins2. Light your subject and background separately.If you want to get a 100% seamless white background you need to think of your lighting in two different stages: the background and the subject. By separating the lights used on your subject and your background you can minimize shadows and hotspots in your image. This does of course require you to use (at least) two separate lights to light your scene, but the added control is well worth it.3. Distance your subject from the backdrop.By separating the distance between your subject and your background you make it easier to minimize falloff from different light sources. If you think about it, the background works like a giant white reflector so the more space you put between your subject and the backdrop the less light is going to bounce off that reflector and hit your subject. Having a great distance between your subject and the background also minimizes your risk of having shadows hit your backdrop.4. Use a light meter for the background.When working with with a seamless backdrop a light meter can really come in handy. One trick is to properly expose the background then move your aperture 1.5 stops higher to make it blown out. Overexpose it and you run the risk of creating white feather edges around your subject.6. Use the histogram AND your eyes.Histograms may be a quick useful tool but there is no alternative to simply using your eyes to judge the scene. A histogram can’t tell you if your scene is evenly lit.7. Flag your lights.Spill suppression is incredibly important when working with a seamless background. You don’t want the light hitting your subject to hit your background and vice-versa, this is where flags come into play. By flagging light you can control the direction of a light giving you much more control over the scene. If you’re short on professional flagging equipment, a few clamps, light stand, and some white poster board will do the trick. Flagging light away from your lens is also a great way to prevent any unwanted lens flares.8. Use a production monitor with exposure peaking.A production monitor is a worthwhile investment, as they can accurately tell you if your background is consistently lit. Recording tools such as the Ninja Atmos also have exposure peaking and focus peaking built-in.The Ninja Atomos shows exposure peaking in the form of zebra stripes on the right.9. Use diffused light on your subject.To get the ‘Apple’ look you will want your subject softly lit. This will mean using at least 3 lights, 1 for your background and 2 for your subject.10. Find a look you want to emulate.Whether it’s the ‘Apple’ look (or another type of lighting setup) you can figure out light placement by looking at the eyes of the subject and study the set up. By examining the eyes of the subject below we can tell that this photographer likely used an Octobox above and to the right of the subject and a large reflector below and slightly to the left of the subject.Over at DVXUser, contributor Bruce Southerland makes a guess as to exactly how the Apple videos are lit:In the Apple spots, the actors are lit with a soft source from high & a little right-just enough to give a little shadow to the opposite side of the face & under the chin. They probably use some fill, based on the density of the shadows on the neck (maybe just the white floor), but they do not use a reflector down low. In the close ups, it looks as though they are using light modifiers to reduce/diffuse the amount of reflections on the left & right edges of the face(the reflections are very minimal). It also looks as though they controlled the fill light & reflections to have a nice medium shadow side to the face.  It’s best to approach this type of light setup with patience and willingness to experiment! Any tips you can share on getting the Apple look? Share in the comments below!last_img read more

No time to adapt

first_imgLess than a month from now, the Ranji Trophy – India’s premier first- class tournament – gets underway on November 2. Yet, top cricketers from across the country aren’t bringing their white flannels out of the closet. Instead, they are busy training in South Africa for the Champions League Twenty20, which begins next week.In the past, it was the Syed Mushtaq Ali Trophy – the domestic T20 tournament – that preceded the Ranji Trophy, but the Board of Control for Cricket in India (BCCI) then decided it wasn’t the ideal preparation for four- day cricket, and the Duleep Trophy was brought forward. But for the premier players, the preparation will be the CLT20, which is played with the BCCI’s blessing.From a burnt-out Mahendra Singh Dhoni to an injured Virender Sehwag, all these players have their sights set on bagging glory for their franchises against the top domestic sides from around the world.Speaking to Mail Today , former India and Delhi opener Aakash Chopra feels while the experienced campaigners can still adapt to the formats quickly, it’s the youngsters who will suffer most.”In an ideal scenario, one would obviously want to have a long camp going into the Ranji season. I have often brought up the issue, but to no avail. While the seniors shouldn’t be too fazed by the transition in formats, the juniors will definitely take more time. But then that is how the game has evolved in the modern day. You need to perform at any cost or perish,” he said.”What makes it more difficult for Delhi is that even their coach, Vijay Dahiya, will have to undergo a transition in planning as he will be returning after fulfilling his duty as assistant coach with the Kolkata Knight Riders.” Interestingly, if Delhi Daredevils, Kolkata Knight Riders or Mumbai Indians make it to the CLT20 final, most of their players will have just four days to adapt as Delhi, Bengal and Mumbai start their Ranji Trophy campaign on November 2 itself.Back home, what makes matters worse for Delhi is that nine of their top 15 players are busy in South Africa while ideally they should have been in India and attending a camp for the upcoming Ranji season – a norm followed by every state team for close to a month before the start of every season.Although the fringe players did attend the camp held in the Capital last month, most of the top players were either busy on national duty or working on their fitness at the National Cricket Academy. Even Dahiya was absent as he was with the Knight Riders, preparing for the CLT20.While Sehwag, Unmukt Chand, Punit Bisht and Yogesh Nagar will be plying their trade for the Daredevils in South Africa, Gautam Gambhir, Rajat Bhatia and Pradeep Sangwan will be donning the KKR jersey and Pawan Suyal will be in the squad for the Mumbai Indians.One of the core members of the Delhi Ranji team, whose IPL franchise didn’t qualify for the CLT20, feels it is very important for the players to attend a camp and adapt to the longer version of the game.”It is important that all the players get together and train because it isn’t easy to adapt from the shortest to the longest format. Also, to know every teammate’s strengths and weaknesses ahead of the season helps the team gel and stay positive going into the season,” the player told M AIL T ODAY . Another member, who is presently in South Africa, feels things are going to be really tough if his team gets into the final stages of the CLT20.”It will be definitely tough for us, also because there will be a change in conditions as well.The pitches here in South Africa will definitely be more conducive to the bowlers unlike those back home,” he told MAIL TODAY . With the Indian team’s performances across formats nosediving, it is high time the premier first- class tournament in the country got more respect and stopped being treated as a poor cousin of the cash- rich T20 leagues.advertisementlast_img read more