As an introductory programming book, it might be more helpful to first introduce the reader to programming, generally, even though the book focuses on Java, specifically. The introduction jumps right in to Java history and architecture. Non-essential chapters of the book are identified early. The book does well dividing topics in to small, logical, self-contained sections with relevant examples. After the first few examples, the reader will recognize the format and what they should expect from BlueJ if they work through an example themselves. The language and delivery of concepts is consistent throughout the book. With the exception of a few concepts or terms in the beginning chapters, terms are carefully introduced. Examples are worked through slowly for an introductory programmer. Sentences are not complicated and the language is concise. The language of the book is easy to follow. Other changes will likely also be easy to integrate with the existing text. The section on variables could be fairly simply updated to incorporate the “var” keyword if the author chooses to do so in the future. Since the book doesn’t take great advantage of BlueJ’s codpad, the jshell update is mostly irrelevant. That won’t break anything that’s in the book and no static book can account for these changes anyway. The book also uses BlueJ in a way that is likely to stay fairly consistent, but with recent updates to the JDK (such as jshell in JDK 9 and “var” in Java 10), tools like BlueJ may be updated to incorporate these beginner-friendly features. Since this focuses on basic Java concepts that aren’t likely to change, this aspect of the book will be long lived. The primary content is related to the reader accurately. There are some minor typos with snippets of program syntax, but these can lead to confusion. comments aren’t given a complete explanation before being used in example programs) The coverage of these topics is complete enough to answer most questions an intro student may come up with when introduced to the basics, but there are some notable exceptions (ex. For the topics that are covered, the book is quite exhaustive, covering small details of syntax that students may or may not encounter in their first year or two. There are, of course, many Java topics not covered by this book, but the book does a good job of covering important concepts for an introductory programming course. Reviewed by Joseph Kendall-Morwick, Assistant Professor, Missouri Western State University on 5/21/18 Journalism, Media Studies & Communications +.
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Early transistor radios required a 22 + 1⁄ 2-volt battery. īefore the mid-1950s, in the days of vacuum tube (valve) radios used batteries designed specifically for vacuum tubes, there was a nine-volt grid bias battery or (US) "C" battery, which had taps for various voltages from 1.5 to 9 volts.Įarly transistorized radios and other equipment needed a suitable voltage miniature battery. Modern batteries have higher capacities and lower internal resistances than early versions. Only the PP3, PP6, PP7 and PP9 sizes are still manufactured, with the PP3 being extremely common. The PP11 consists of two isolated 4.5-volt batteries with four terminals. The PP3 battery was added as an ANSI standard in 1959, currently known as ANSI-1604A. The company says that it introduced the PP3 battery in 1956. Historically, the now popular PP3 battery size was a member of the power pack (PP) battery family that was originally manufactured by Ever Ready in the United Kingdom and Eveready in the United States. PP (Power Pack) battery family from left to right: PP1, PP3, PP4, PP6, PP7, PP8, PP9, PP10, PP11 ĩ-volt batteries accounted for 4% of alkaline primary battery sales in the United States in 2007, and 2% of primary battery sales and 2% of secondary (rechargeable) battery sales in Switzerland in 2008. Primary lithium types are made with three cells in series. Carbon-zinc types are made with six flat cells in a stack, enclosed in a moisture-resistant wrapper to prevent drying. These cells are slightly smaller than LR8D425 AAAA cells and can be used in their place for some devices, even though they are 3.5 mm shorter. Most PP3-size alkaline batteries are constructed of six individual cylindrical 1.5 V LR61 cells enclosed in a wrapper. A few other 9-volt battery sizes are available: A10 and A29. A range of PP batteries was produced in the past, with voltages of 4.5, 6, and 9 volts and different capacities the larger 9-volt PP6, PP7, and PP9 are still available. The size, regardless of chemistry, is commonly designated PP3-a designation originally reserved solely for carbon-zinc, or in some countries, E or E-block. Designations for this format include NEDA 1604 and IEC 6F22 (for zinc-carbon) or MN1604 6LR61 (for alkaline). Mercury batteries of this format, once common, have been banned in many countries due to their toxicity. The nine-volt PP3-size battery is commonly available in primary zinc-carbon and alkaline chemistry, in primary lithium iron disulfide and lithium manganese dioxide (sometimes designated CRV9 ), and in rechargeable form in nickel-cadmium (Ni–Cd), nickel-metal hydride (Ni–MH) and lithium-ion. This type is commonly used for many applications including household uses such as smoke and gas detectors, clocks, and toys. The PP3 has a rectangular prism shape with rounded edges and two polarized snap connectors on the top. Batteries of various sizes and capacities are manufactured a very common size is known as PP3, introduced for early transistor radios. Actual voltage measures 7.2 to 9.6 volts, depending on battery chemistry. The nine-volt battery, or 9-volt battery, is an electric battery that supplies a nominal voltage of 9 volts. Size comparison of batteries: D, C, AA, AAA, AAAA, PP3 (9-volt) This app is available on both iOS and Android and using it, you can gain followers. However, it is important you know that the followers you are getting are fake followers and as such, you shouldn’t expect any form of engagement from them.Īnother app that you can use to gain new followers is the Followers Gallery which is a rebrand. The app is quite easy to use as it is intuitive even to first-time users. When the points reach a certain threshold, you can then use it to get followers. The service will get you to like a certain post and in return, you are credited with points. Turbo Followers trades like for followers. This application has been developed for both the Android and iOS platforms and with it, you can gain new followers without paying for them with money. Turbo Followers is one of the best Instagram follower apps in the market. The followers you are provided would have profile pictures and not egg profiles with no profile pictures or regular posts. Insta Follower Pro is quite fast and easy to use even for first-time users. The task is nothing difficult - it is just you following the profile of other Instagram users and then you get coins in return. If you do not want to carry out any tasks, then you will have to pay to get coins and then use the coins. It is the coins you earned from the tasks allocated to you that you will use to buy the followers. This service provides an Android app you would install for free and then take up the tasks provided to earn coins. The Insta Followers Pro is one of the options out there if you want to gain new followers. In this section of the article, we would be recommending some of the top options out there that we know worked at the time the article was written. Unfortunately, not all of them keep to the promise and for that reason, you need to be picky in terms of the one you use. There are many apps in the market that promise to provide you with Instagram followers if installed. With this known, let’s move to the recommendations.īest Instagram Followers Apps (Quickly & Safe) There is also the case of you losing those followers as time goes on.įor these reasons, it is advisable you only use any of these apps as a small part of your strategy as the followers you will get at best would be ghost followers - and you can even get suspended in the process. Ghost followers are the followers that never engage with your content. Regardless of the method followed one thing is clear - followers provided by using an app are most likely fake followers AKA bot followers and even if they are not - they would turn into ghost followers. That is how they work and that is why before installing any Instagram follower app, you need to know how the apps make it money or even provide you followers in the first place. However, it is hard to believe a non-profit service will be set up to provide you with followers for free.įor the most part, while these apps are free, they require you to carry out certain tasks or even use your phone for undisclosed uses and in turn, you are provided followers. Some of these apps would even taunt themselves as free as you won’t be using cash to pay for the followers. The idea behind installing an app and using it to gain followers is something everyone would jump on. Before doing that, let take a look at an overview of the method. In this article, we would be recommending some of the top Instagram followers apps that you can use. However, when dealing with an app that requires you to log into your account, you are always at the risk of getting such an IG account compromised and that is why you need to only use an app that can be trusted. While there are many methods you can use to gain followers, our focus in this article is the apps you can install and use to gain followers - of them are even free. This is because even some low-level celebrities end up gaming the system as it is increasingly becoming difficult to gain followers on the scale you want as a new account. However, gaining followers is not as easy as is stated in the Instagram guidelines and if you are to go by that, you will most likely not get the number of followers you ever wanted especially if you are not a big name. This is because if you have many followers, you get some form of social credibility that would get others to want to interact with your posts and even account. While you will want to engage with your existing followers, gaining more followers and retaining them is at the top of the priorities of most Instagram users. If you are looking for such apps, then the article below has been written for you as we would be recommending some of the top Instagram followers apps in the market. There are apps you can use to gain Instagram followers and increase your fan base. There are many eco-lodges and eco-camps around the Lut desert in the western and southern parts of the area. Nowadays, tourism is an important activity and cities around the Lut desert such as Kerman, Shahdad, Bam, Nehbandan, Birjand, Fahraj, Zahedan and Nosrat Abad offer different tourism facilities such as hotels, restaurants, markets, and transportation. It was inscribed based on criteria VII to contain superlative natural phenomena or areas of exceptional natural beauty and aesthetic importance and VIII to be outstanding examples representing major stages of earth's history, including the record of life, significant on-going geological processes in the development of landforms, or significant geomorphic or physiographic features. Lut Desert was inscribed on the World Heritage List in 2016. Based on archeological evidence, the region contains 7,000 years of human culture and civilization. The western fringe of Lut Plain (Shahdad Plain), despite its proximity to the arid and hot desert of Lut, had been selected for living by the ancient men. Since the 5th millennium B.C the region has always been inhabited by human societies. The living of human beings in Lut Plain Region dates back to 7000 years ago. Through the last ten centuries, when the city of Shahdad was known as ‘Khabis’, it was an important trading place on the so-called ‘silk road’ connecting the seaports on the Persian Gulf to Middle Asian regions and also the distant regions in the East and West. History & TodayĪpart from the unique natural landscape of Lut, the cultural/archaeological landscape of western fringe of the Lut Desert is very well-known and important in Near Eastern archaeology. The yardangs in this desert are so extensive it is said that they can be seen from space The hottest spot on Earth with more than 70 degrees celsius recorded by NASA in 2005 in the southwest of Rig-e Yallan. Some of its important natural features are the highest sand dunes of the world with more than 475 meters high, situated in Rig-e Yallan The highest kalutes (yardangs) throughout the world with more than 155 meters high. The high number of natural phenomena throughout the year and the richness of culture in the local communities, turn this desert into a place of natural and cultural importance. Landform evolution in the Quaternary period in this desert represents a particular history of geological and geomorphological changes. The river flows along 2000 km long, from Ravar Mountains passing the west margin of Gandom Beryan into the salt depression. The presence of the river in Lut increases the singularity of the desert. Another unique feature of the desert is the Shur river. The Hamada plain in the central part of the Lut has a reverse triangular shape pointing towards the south to Shurgaz Hamun playa. The severe hot daily temperature decomposes rock outcrops in the mountains that get deposited on the plains. The geomorphologic conditions of the central part of the Lut are developed as a pebble and sand plain. The area of the core zone is about 23,000 square kilometers and the protected area, that works as a buffer zone, is about 18,000 square kilometers which includes Rig- e Yallan (sand dunes), Kalut (yardang), Nebka (depressions), Shur river, Gandom Beryan (plateau covered With dark lava) and the central Hamada (Desert pavement). The Lut Desert is located in the southeast part of Iran among three provinces of Kerman, Sistano Baluchestan, and Khorasan-e Jonubi. The therapeutic effects of qigong in patients with chronic obstructive pulmonary disease in the stable stage: a meta-analysis. Efficacy and tolerability of a polysaccharide-resin-honey based cough syrup as compared to carbocysteine syrup for children with colds: a randomized, single-blinded, multicenter study. doi:10.1002/3Ĭohen HA, Hoshen M, Gur S, Bahir A, Laks Y, Blau H. Chronic sinusitis occurs when the spaces inside your nose and head (sinuses) are swollen and inflamed for three months or longer, despite treatment. Chest physiotherapy compared to no chest physiotherapy for cystic fibrosis. But don’t worry, as you will easily get rid of your stuffy nose within a short time. Mucolytics for COPD: negotiating a slippery slope towards proof of efficacy. What Causes Nasal Mucus Plug If you have a nasal mucus plug, it might be due to the reasons listed below. Mucolytic agents versus placebo for chronic bronchitis or chronic obstructive pulmonary disease. Qigong, a practice of breathing exercises and movements, may also help.A few herbs-including mao huang ( Herba ephedrae), tao ren ( Semen persicae), and Huang qin ( Radix scutellariae)-may ease the symptoms of respiratory disease.Either caused by allergens or by any environmental factors, swollen sinuses give you that stuffy feeling in your nose that makes breathing hard. While there are anecdotal reports that they are helpful, the scientific data is not clear about the benefits. Berg Watch on Clogged nose Aching face You might just have swollen sinuses. Chinese medicine: Chinese herbs and treatments have traditionally been used to reduce mucus in the lungs.However, it is not clear whether honey specifically helps in coughing up mucus.
If the data in the document is confidential, then you can set the Open and Permission password to secure the PDF using this software. In addition to editing the content of your document, this program is capable of converting your PDF file to other file formats such as Word, HTML, and Excel. PDFelement for Mac is among the best PDF editor currently and it is thought to be having the greatest editing tools. PDFelement for Mac is the best tool to employ when working with PDF files since it is a multifunctional tool. Each of them has its strength and weakness, however, you will not regret it if you indulge in PDFelement for Mac as your PDF editor. There are numerous tools that offline as well as online programs that can be used to edit your document. Most of the time when working with PDF files you will be required to edit some or the entire content of the document to fit specific standards or for various purposes. Best PDF Editor to Improve Productivity - PDFelement for MacĬonsidering that PDF is the most document file format used in the world then you should be looking for the best PDF editor. Setting up a password for your Wi-Fi connection will keep unauthorized or creeping neighbors from your Wi-Fi connection. When too many devices are connected to the same router in your home then it is obvious that the internet connection will be slow. These obstacles will disrupt your Wi-Fi signal and lead to a slow internet connection. The router should be placed at a considerable distance away from metal and electrical appliances that emit electromagnetic waves such as dishwashers and microwaves. You can now check the internet speed to see if there is any change.įor best and a strong Wi-Fi signal the router should be placed in an elevated place. Turn off the Wi-Fi router, wait for about a minute and then turn it on. The easiest way to try and get a strong signal on macOS 11 is to reboot your router. It’s not at all times that your computer or phone could be the cause of the slow internet connection, sometimes it could be the router. Your Mac computer will diagnose the internet connection and notify you if there is a problem. Tap on the Assist button, select Diagnostics, specify the Wi-Fi signal, and click on the Continue button. Go to the Apple menu on your Mac, click on the “System Preference” tab, and select the “Network” option. However, if the speed does not match, then follow the steps below to learn how to speed up your Wi-Fi on macOS 11. If the internet speed matches the one you are paying for then you should make plans to upgrade your Wi-Fi connection. There are a couple of tools that can be used to test the signal strength of your Wi-Fi such as Speedtest. This is the first thing that you should do when your Wi-Fi signal is weak. You can happily enjoy the internet speed within the Wi-Fi signal range.A strong Wi-Fi signal won't slug you down when performing an online assignment or when working online.You can comfortably connect to multiple devices.Why should I improve my weak Wi-Fi signal? There would no delayed email notification, you can easily connect and even make video calls, quick websites loading, and smooth streaming of videos. How to Boost Your Wi-Fi SignalĪ strong Wi-Fi signal and a fast internet speed are necessary to ensure a smooth and seamless run of activities on your Mac computer. Let’s go deeper and look at how you can boost your Wi-Fi signal on macOS 11. There are a number of factors that could be the cause of the weak Wi-Fi signal. However, sometimes the Wi-Fi signal may be too weak that it would even take ages to load a website. A Wi-Fi connection is cheaper and better in the long run than wholly depending on the data plans because you can comfortably connect multiple devices and it is much faster. Most of the things we do on our computer or mobile phones require an active and steady internet connection. Microsoft Excel for macOS 10.14 Crashes.Numbers File Can’t Be Open on macOS 10.14.Can’t Open Keynote Files on macOS 10.14.macOS 10.14 Update Not Showing on App Store.Alternatives to Adobe Acrobat for macOS 10.14.Mac Won’t Wake from Sleep on mac OS 10.14. Black Screen after Upgrade to macOS 10.14.Time Machine Stuck on Preparing Backup in macOS 10.14.Apps Freeze or Quit Unexpectedly on macOS 10.14.Merge and Remove Duplicate Contacts on macOS 10.14.Remove and Rearrange Menu Bar Icons on macOS 10.14.Edit Photos with Preview in macOS 10.14.Method to Back Up Data on Mac before Updating into 10.14. You will need a 50 to 30 adapter if you park in a 50-amp campground and your RV is only wired for 30 amps. This will depend on how your RV or travel trailer is wired. This brings up an interesting topic of what adapters to use. That means that you will have to have a plug that matches that receptacle to get the power to your RV or trailer. The standard plug for most RVs and travel trailers will be the TT-30. If the campground does both is often a rare exception if they do it at all. When you pull into a campground, you will find that the campground may be 50-amp or 30-amp only. Making a mistake can only be fixed by going back to the store and making an exchange for the right options. This just means that you cannot be in a hurry when looking for either the plug or the outlet. Even the uncommon options will have their own special outlet to plug into. They will have a similar NEMA number to help you identify them. There will be as many receptacle designs as there are plugs. It is very simple to do and should only be a matter of seconds to get the right outlet. In other words, to find the right receptacle you just match the prongs to the holes and you got the right one. They can only plug into the one that looks like the prong side of the plug. This is a simple match to make as you cannot plug the wrong plug into the wrong outlet. The word receptacle simply means the outlet you need to plug the plug into. But how those prongs are arranged is another matter. It is mainly for 110 or 120 outlets and you only need a hot, neutral, and ground wire to make the plug work in a 120 outlet. Know what you are looking for so your search for a replacement goes smoother. There is also a 20-amp dryer plug on the market so be careful how you phrase your request. Then add the word 30 to your phrase to make sure you get a 30 amp option and not a 50 amp one. You may have to use an extra word, like dryer plug to get close to the exact plug you need. The L stands for locking as the TT stands for travel trailer. Individual plugs may have special labels, like the TT-30 above, but that is because they have a special use. A 30-amp plug is called a 30-amp plug as any other name would confuse the world and make it more difficult for people to find what they are looking for. There is no special name for these plugs. They should get you on the right track to finding the right replacement. Talk to your electrical expert and see what all the plugs are and what they are for. These are not all the 30-amp plugs you can buy but they are the most common ones you would encounter. L6-30 (locking 240 volt 30amp) Twist-Lock 30A 240 volt outlet, easy to find in stores, works great for adding adapters to portables EVSE’s equipped with a L6-30 plug ( source) TT-30 (Travel Trailer 30amp) 30A 120-volt 3-prong outlet, the older style found in RV parks, not used in residential homes. 14-30 standard 30A 240 volt 4-prong Dryer outlet found in homes built in 1996 and newer 10-30 standard 30A 240 volt 3-prong Dryer outlet found in homes built before 1996 Here is a brief list of those different plugs and their use: Are There Different Types Of 30 Amp RV Plugs? The plug you need for your travel trailer should be marked TT-30 and this is for those older campgrounds using an older electrical system that has been in place for a very long time. You need to take a few minutes to examine the prongs and see if they will work for your intended use. This means you just can’t walk into an outlet selling electrical parts and just pick up one and go home. Those dryer plugs can be for either 240 or 120 volts. The one you buy will depend on the make and model of the dryer. 3 were for a welder or plasma cutter (or similar work tools). They all have different purposes and they can be for either 240 or 120 power.ģ of those plugs were for your RV or travel trailer. On one chart we saw about 8 differently designed 30-amp plugs. A 100ml bottle of the award-winning 10x Concentrate Dr. Gazillion Premium Quality 2 Litre GIANT Bubble Mixture/Solution for Bubble Machines, bubble wands and parties. The bubble wands are handmade with sustainably sourced wood and 100% fair-trade natural untreated cotton with a special braid, designed to soak up as much bubble juice and release it slowly to create the most amazing giant bubbles! Everything is made ethically in North Wales of the U.K. Laeto Bubble Waves Giant Bubbles Kit with Solution and Wand Ideal Kids Toys for Outdoor Garden Games for Adults and Children. The award-winning eco-friendly and biodegradable quality bubble solution is free from phosphate, palm-oil and parabens, developed by a marine conservationist with over 8 years of research and tested to perfection Perfect for introducing the whimsical world of giant bubbles, it makes a wonderful small gift for anyone in any occasions to bring lots of smiles and fun times! Great to bring along to outings and holidays to capture some stunning memories with these gorgeous multi-color bubbles. Giant Bubble Wands are MADE IN AUSTRALIA Where our AUSTRALIAN MADE Giant Bubble Wands bring laughter and happiness to children and adults alike, and Whistling Water Bird Whistles bring an instant smile. Bubble Play 6 Pack -4oz of Bubble Wands Giant Bubble Blowers for Kids in Assorted Rainbow Colors Large Sticks Come w/ Soap Solution & Wands All-in-One. Unimaginably Giant Bubbles: These giant bubble wands create long, GIANT bubbles thanks to a 2-handle design, which has been used to set every big bubble wo. The “My First Giant Bubble Kit” has everything you need to create the most incredible long lasting giant bubbles for hours of amazing bubbling fun that delights everyone young and old The body and lid are made from metal and the whole assembly is very solid. At £3,299 for the fully-loaded model, it looks almost cheap compared to the Duo 16 but it lacks the gaming credibility of the Windows machines listed above.Īsus ROG Zephyrus Duo 16 review: Design, build quality and key featuresĪs you'd have every right to expect of a laptop costing £4,500 the Asus ROG Zephyrus Duo 16 is very well made. The latest Dell XPS 17 may not have the absolute graphics horsepower of the Duo 16 but its Nvidia RTX 3050 GPU is still potent enough for most creative tasks and you can specify a 4K monitor and only pay £2,400 for the privilege.įinally, Apple’s 16in MacBook Pro deserves a look by dint of its lovely display, stellar battery life and all-around desirability. The ROG Strix Scar 15 is a thoroughbred gamer with all the bells and whistles and can be specified with Intel’s monster Core i9-12900H chip for under £4,000, while the ROG Zephyrus M16 is a little less adolescent in design and has a more creator-friendly 16in 16:10 display. Two of the Duo’s Asus stablemates are worth a look, too, both built around Intel’s new Alder Lake Core i7 processor. The Blade 17 range starts at £2,899 but the top end 4K model is the same price as the 4K Duo 16 £4,499. The Blade 17 is also beautifully made, very powerful and its sound system is excellent. It may have only one screen but it’s large at 17.3in and sharp, too, at 3,840 x 2,160. One obvious choice is the latest Razer Blade 17. However, there are plenty of high-end laptops around that are aimed at both the serious gamer and the serious creator, just like the Zephyrus Duo 16. Given that no other laptop on the market has a trick two-screen mechanism, there aren’t any like-for-like rivals. The all-the-bells-and-whistles model, which comes with an AMD Ryzen 9 6900HX CPU, an RTX 3080 Ti GPU and the hybrid resolution screen will set you back £4,499. The cheapest model on sale in the UK is based on an AMD Ryzen 7 6800H CPU and an Nvidia GeForce RTX 3070 Ti GPU for £2,699. You can also pick from either a 1,920 x 1,080 a 2,560 x 1,600 (both 165Hz) or a hybrid 4K 120Hz / 2K 240Hz screen. You can choose from an AMD Ryzen 7 or Ryzen 9 CPU and an Nvidia RTX 3060, 3070Ti or 3080Ti GPU. This being Asus it’s not an easy thing to say exactly which models are available in which territory and for how much. READ NEXT: Our selection of the top gaming laptops available Asus ROG Zephyrus Duo 16 review: Price and competitionĬonfiguration tested: AMD Ryzen 9 6900HX CPU, Nvidia GeForce RTX 3080Ti GPU, 32GB RAM, 16GB vRAM, 4TB SSD, 16in 3,840 x 2,160 IPS non-touchscreen, 14in 3,840 by 1,110 IPS touchscreen. All this trickery doesn't come cheap but then Duo laptops were never intended to be affordable. Internally, the new Duo 16 also gets the latest Nvidia mobile graphics – up to a GeForce RTX 3080Ti GPU – and the latest 6000-series AMD CPUs, including the eight-core AMD Ryzen 9 6900HX, which is unlocked if you fancy a bit of cheeky overclocking. The mechanism behind the innovative second-screen has also been modified in a significant way. Despite the larger screen the Duo 16 is actually fractionally smaller than the Duo 15 and only 100g heavier. Out goes the 15's 15.6in 16:9 panel to be replaced by a 16in 16:10 affair. The main difference between the Zephyrus Duo 15 and 16 is, surprise surprise, the size of the main screen. Now, there’s a new, improved model called the Zephyrus Duo 16.Īsus ROG Zephyrus Duo 16 review: What you need to know The Asus’ ROG Zephyrus Duo 15 was an exception because, although a bit strange, the press liked it and customers bought into the idea. No, of course you don’t, because they were all weird ideas doomed to failure. Do you recall the Lenovo ThinkPad 700ds with its slide-out second screen? The Asus Taichi with a screen on both sides of the lid? Or the Acer Iconia 6120 with a touchscreen where the keyboard should have been? Generally, these don’t work and fade from memory. Some laptop manufacturers seem determined to reinvent the wheel with odd designs and esoteric features nobody asked for. It provided improved resolution and sensitivity, enabling operators to see features such as cold fronts, thunderstorm gust fronts, and mesoscale to even storm scale features of thunderstorms that had never been visible on radar. The new system provided Doppler velocity, improving tornado prediction ability by detecting rotation present within the storm at different scan angles. The NEXRAD radars incorporated a number of improvements over the radar systems that were previously in use. Where possible, they were co-located with NWS Weather Forecast Offices (WFOs) to permit quicker access by maintenance technicians. The site locations were strategically chosen to provide overlapping coverage between radars in case one failed during a severe weather event. Smith, Arkansas, following the initial installations. In 2011, the new Langley Hill NEXRAD was added at Langley Hill, Washington to better cover the Pacific Coast of that area other radars also filled gaps in coverage at Evansville, Indiana and Ft. The last system deployed as part of the installation program was installed in North Webster, Indiana on August 30, 1997. The first installation of a WSR-88D for operational use in daily forecasting was in Sterling, Virginia on June 12, 1992. Installation of an operational prototype was completed in the fall of 1990 in Norman, Oklahoma. Unisys was selected as the contractor, and was awarded a full-scale production contract in January 1990. However, it took four years to allow the prospective contractors to develop their proprietary models. Radar systems developed by Raytheon and Unisys were tested during the 1980s. The JSPO group opted to select a contractor to develop and produce the radars that would be used for the national network. When the proposal was presented to the Reagan administration, two options were considered to build the radar systems: allow corporate bids to build the systems based on the schematics of the previously developed prototype radar or seek contractors to build their own systems using predetermined specifications. That year, the NSSL completed a formal report on developing the NEXRAD system. In 1979, the NEXRAD Joint System Program Office (JSPO) was formed to move forward with the development and deployment of the proposed NEXRAD radar network. A working group that included the JDOP published a paper providing the concepts for the development and operation of a national weather radar network. Air Force, found that Doppler radar provided much improved early detection of severe thunderstorms. Tests over the next three years, conducted by the National Weather Service and the Air Weather Service agency of the U.S. The Joint Doppler Operational Project (JDOP) was formed in 1976 at the National Severe Storms Laboratory (NSSL) to study the usefulness of using Doppler radar to identify severe and tornadic thunderstorms. Neither system employed Doppler technology, which provides wind speed and direction information. The radar network consisted of WSR-57 developed in 1957, and WSR-74 developed in 1974. Departments of Commerce, Defense, and Transportation, agreed that to better serve their operational needs, the existing national radar network needed to be replaced. Testbed of the WSR-88D on display at the National Severe Storms Laboratory. NEXRAD has an increased emphasis on automation, including the use of algorithms and automated volume scans. The radar system operates in two basic modes, selectable by the operator – a slow-scanning clear-air mode for analyzing air movements when there is little or no activity in the area, and a precipitation mode, with a faster scan for tracking active weather. It returns data which when processed can be displayed in a mosaic map which shows patterns of precipitation and its movement. NEXRAD detects precipitation and atmospheric movement or wind. Its technical name is WSR-88D ( Weather Surveillance Radar, 1988, Doppler). Air Force within the Department of Defense. NEXRAD or Nexrad ( Next-Generation Radar) is a network of 160 high-resolution S-band Doppler weather radars operated by the National Weather Service (NWS), an agency of the National Oceanic and Atmospheric Administration (NOAA) within the United States Department of Commerce, the Federal Aviation Administration (FAA) within the Department of Transportation, and the U.S. NEXRAD Radar at the WSR-88D Radar Operations Center. |
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