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高中选修八第五单元单词高中选修八第五单元单词在高中选修八的第五单元中，我们学习了许多有趣且实用的单词。
这些单词不仅丰富了我们的词汇量，还帮助我们更好地理解和运用英语。
在这篇文章中，我将介绍一些我认为最有趣和有用的单词。
首先，让我们来谈谈“innovation”（创新）。
创新是现代社会发展的关键驱动力之一。
它指的是通过引入新思想、方法或产品来改变和改进现有事物。
创新不仅在科技领域中起着重要作用，也在商业、教育和艺术等各个领域中发挥着重要作用。
正是因为创新，我们才能不断进步和发展。
接下来是“sustainability”（可持续性）。
可持续性是指满足当前需求而不损害未来世代满足其需求的能力。
在当今社会，可持续性已成为一个热门话题。
人们越来越意识到保护环境、节约资源以及推动经济和社会发展之间的平衡至关重要。
通过采取可持续性措施，我们可以为未来创造一个更美好的世界。
另一个有趣的单词是“diversity”（多样性）。
多样性指的是不同个体、事物或观点之间的差异和变化。
在一个多元化的社会中，我们可以从不同文化、背景和经验中学到很多东西。
多样性不仅能够促进创新和发展，还能够增强人们之间的理解和尊重。
此外，我们还学习了“globalization”（全球化）这个词。
全球化是指各国之间经济、文化和政治联系日益紧密的趋势。
随着科技的进步和交通运输的发展，世界变得越来越紧密相连。
全球化带来了许多机遇，但也带来了一些挑战。
我们需要适应这个不断变化的世界，并学会在全球范围内合作和交流。
最后一个单词是“resilience”（韧性）。
韧性指的是面对困难、挫折或压力时保持坚韧和适应能力。
在生活中，我们经常面临各种挑战和困难。
拥有韧性意味着我们能够从失败中学习，适应变化，并坚持追求目标。
韧性是成功的关键之一。
通过学习这些单词，我们不仅扩大了词汇量，还了解了一些重要的概念和价值观。
这些单词在我们的日常生活中起着重要作用，并且将对我们未来的发展产生积极影响。
未来我的家乡会变成什么样英语作文全文共3篇示例，供读者参考篇1What Will My Hometown Be Like in the Future?Imagine a world where flying cars zip through the sky, robots do all the chores, and people can teleport from place to place! That's what I think my hometown of Oakville will be like in the future. The world is changing so fast with new inventions and technologies emerging every day. I can't wait to see how my town transforms in the coming years. Here's what I envision for the future of my beloved Oakville.To begin with, I foresee the way we get around town undergoing a huge makeover. Instead of the loud, polluting cars and buses of today, I think we'll be gliding along in sleek,eco-friendly vehicles. Flying cars that run on electricity or solar power could very well be a reality, allowing us to soar above traffic jams. Personalrobotic vehicles might also pick us up and drop us off wherever we need to go, all controlled by voice commands or smart phone apps. How cool would that be?Our roads and transportation systems will need to change dramatically to accommodate all these new ways of traveling. Imagine roads designed just for driverless car lanes, separate lanes for bicycles and scooters, and lanes designated for pedestrians moving on futuristic hoverboards or powered sneakers. There could even be lanes in the sky specifically for flying cars! Stoplights might become a thing of the past, replaced by intelligent traffic sensors and signals that optimize traffic flow.Speaking of traffic flow, I bet getting around Oakville will be a total breeze since we'll all be working remotely from home. Can you picture waking up, walking just a few feet to your home office pod, and videoconferencing with coworkers and clients all over the world? No more spending hours stuck in your car during a hectic commute. With virtual reality meetings, it will feel like you're all in the same room even though you're miles apart. Productivity will soar and we'll have more free time to spend with family and friends.Of course, our homes themselves are bound to evolve too. I can picture houses made of ultra-strong but lightweight materials like carbon fiber or specialized polymers. The homes could be equipped with incredible amenities like personal robotbutlers, smart kitchens that cook gourmet meals at the touch of a button, and climate control systems that automatically adjust to our preferred temperatures.Gardens on the roofs and walls filled with fruits, vegetables, and herbs will provide hyper-local sources of food too. Imagine walking out to your mini rooftop greenhouse and picking fresh lettuce, tomatoes, and strawberries for your salad! Any scraps will go into an in-home composter that transforms food waste into nutrient-rich fertilizer. Our entire town could be blanketed in lush greenery this way.The homes of the future will surely be super sustainable and kind to the environment, relying on renewable energy sources like solar panels, wind turbines, and hydrogen fuel cells. Our utilities will be seamlessly integrated into "smart home" systems, maximizing efficiency so we waste little to no water, electricity, or other precious resources. I also wouldn't be surprised if we have incredible new recycling systems that break down and repurpose virtually anything into reusable materials.Outside in the community, I picture Oakville's parks having interactive, educational playgrounds for kids, with augmented reality games and activities that make learning feel like a thrilling adventure. Public libraries could be filled with incredible tech likeholobooks that create holographic illustrations that seem to leap off the pages. Study rooms may have artificial intelligence tutors to assist with homework. Who needs a human teacher when you have an AI that can explain any subject with infinite patience?Shopping will change dramatically too. Instead of piling into a car to go to the mall or grocery store, we'll likely just order everything from personalized online stores. Products will be created on-demand at highly automated local manufacturing centers, using 3D printers for customized clothes, toys, furniture, and more. Then fleets of drones will zip around town delivering packages straight to our doorsteps in record time!Medical care will look extremely futuristic as well. I envision lightning-fast body scanners that can diagnose any ailment in seconds. Robotic surgeons outfitted with specialized micro-tools will fix injuries with mind-boggling precision. Doctors may even be able to bio-print organs and limbs using our own cells. Imagine how many lives that would save!Safety and security should dramatically improve too thanks to incredible new technologies. Tiny robotic insects acting as mobile security cameras will lurk everywhere, instantly detecting and neutralizing threats. DNA and biometric scanners will safeguard homes, schools, and other buildings. With advancedpredictive policing programs to thwart crimes before they occur, Oakville should feel like one of the securest communities on the planet.While some of these predictions may seem straight out of a sci-fi movie, many innovative thinkers and technologists truly believe these sorts of advancements are just over the horizon. And when I look around at how rapidly our smartphones, computers, and other gadgets keep evolving with each passing year, I can definitely envision this incredible high-tech future becoming a reality in places like Oakville.Of course, along with all the wonderful technological marvels, the Oakville of tomorrow will likely still retain a lot of what makes our town so special today - our quaint neighborhoods, incredible school system, and that warm, community spirit that brings everyone together through fun annual events like Oakville Harbourfront Ribfest and the Midnight Madness Festival.Technology may change, but the heart and soul of our hometown will live on through the amazing people who call this place home. Our local parks, libraries, community centers, and other public spaces will surely adapt to keep Oakville a dynamic,engaged town even as mind-blowing new innovations emerge all around us.No matter how advanced and modern Oakville becomes, I'm certain it will still feel like the warm, welcoming place I've always loved. We'll just have way cooler flying cars, robots, and holobooks to enjoy! How incredibly exciting to imagine all the fantastic changes the future has in store. While the road ahead is still uncertain, one thing is for sure - my hometown is destined for an extraordinary transformation over the coming decades. I can't wait to see what awes and amazes us next!篇2What Will My Hometown Be Like in the Future?Can you imagine what my hometown will look like 50 years from now? It's really hard to picture because so many things could change by then! But I've been thinking about it a lot lately and here are some of my ideas.First of all, I think the buildings and houses will look very different. These days, a lot of the buildings downtown are pretty old - some are even over 100 years old! In the future, I bet those old brick buildings will be gone and replaced with huge skyscrapers made of glass and steel. The skyscrapers might evenhave plants and trees growing on the sides to help make the air cleaner. How cool would that be?Instead of the small houses my neighborhood has now, I think there will be giant apartment buildings that can fit hundreds of families. But these won't be like the boring, square apartment buildings we have today. I'm picturing apartment towers that are round or shaped like pyramids or even look like they're leaning over! The future architects will definitely get creative.As for technology, I can't even imagine how advanced it will be 50 years from now. Maybe our houses will have robots that can do all the cleaning and cooking for us. Or maybe we'll have special watches that can listen to what we say and do whatever we ask, kind of like having a personal assistant right on our wrists. How awesome would that be?Video calls will probably be a thing of the past too. I bet we'll have hologram communicators where we can see a 3D projection of the person we're talking to, just like in the movies! We might even be able to project a hologram of ourselves into their room while they project one into ours. It would be like having them actually there with you. So crazy!Outside, I don't think too many people will be driving regular cars anymore. By then, most people will probably be riding around in self-driving electric cars. Maybe the self-driving cars will even be able to fly a little bit above the ground so they don't get stuck in traffic jams. No more annoying traffic for sure!In the sky, I bet there will be drones everywhere delivering packages and food right to people's doorsteps. We'll be able to order stuff from across the world and have it arrive at our homes in just a couple hours via drone. No more having to wait days and days for shipping.As for entertainment, I'm sure video games and movies will look incredibly realistic by then. We might even have special virtual reality headsets that make you feel like you're actually inside the game or movie! Like if you're playing an underwater game, you'll be able to see the fish swimming all around you. You might even be able to reach out and touch them. Wild!Sports will also change a ton in my opinion. Players might have special suits that give them superhuman abilities like being able to run faster, jump higher, and be stronger. That would make sports way more exciting to watch for sure. Imagine how awesome a basketball game would be if the players could dunk from halfway across the court!For learning in schools, we probably won't have to read from boring, flat textbooks anymore. Everything will likely be in 3D or virtual reality so we can see historical events happening all around us and explore the human body from the inside out. Learning that way would be so much more fun and interesting.Downtown is always kind of dirty these days with trash on the streets and pollution in the air. But in 50 years, I bet it will be way cleaner. What if we had tiny robots that could drive around and automatically clean up any litter or mess? Or maybe building roofs could have special filters that remove smog and dust from the air. A cleaner, greener city would be amazing.As for my hometown's parks, I hope we can find ways to preserve nature even as the city grows bigger. It would be awesome to have giant biodomes filled with every type of plant and animal from around the world. We could go explore the biodomes and see lions prowling around, monkeys swinging through the trees, and tropical fish swimming in lakes, all while staying safe behind protective screens or force fields. Exploring those bio-domes would be like going on a safari!Those are just some of my ideas for what the future might look like around here. Designing towering skyscrapers, living with helpful robot assistants, and learning in a fully 3D virtualworld - it all sounds pretty unbelievable right now. But you never know what incredible inventions people will come up with over the next 50 years.I just hope that no matter how crazy the technology gets, my hometown can still feel like home. I want it to be clean, safe, and have plenty of wide open green spaces to explore. Because at the end of the day, this will always be my home and the place where my heart is. Looking forward to an amazing future here!篇3What Will My Hometown Look Like in the Future?Have you ever wondered what the world will be like when we are all grown up? I think about it a lot! I imagine the future will be full of amazing inventions and crazy new technologies. The town I live in now will probably look totally different in 20 or 30 years. Let me tell you about how I picture my hometown in the future!First of all, I think we will finally have flying cars zipping around everywhere in the sky! Can you imagine how cool that would be? Instead of being stuck in traffic jams on the roads, people will just fly their car right over the gridlock. The streets will be way less crowded since most vehicles will take to the air. There will be special landing pads and docking stations set up allover town instead of regular parking lots. Maybe some flying car owners will even build little garages on the roofs of their homes to park their rides!The skies definitely won't be the only things looking different around here in the years ahead. I'll bet all of our homes, schools, stores and other buildings will be built out of super high-tech materials that are stronger, more energy efficient, and better for the environment. Some houses might even be made out of special concrete that can repair its own cracks automatically! The buildings could have solar panels and windmills built right into their design to generate electricity from the sun and wind.Speaking of environmentally friendly, I'm sure my town will be much "greener" overall in the future. We will probably rely a lot more on renewable energy sources like solar, wind and hydroelectric power plants instead of burning fossil fuels that pollute the air. I can picture there being plenty of wide open green spaces with beautiful parks, gardens and nature trails throughout the community too. Protecting forests and wildlife habitats will likely be a big priority.Another thing that will definitely transform is transportation within the town itself. Self-driving electric cars and buses maybecome the main way people get around, making the roads much safer. But I also think there will be even cooler options like personal luggage drone robots that could carry your bags for you or futuristic hyperloop systems where you get shot through vacuum tubes at ultra-high speeds to get across town in mere seconds! How awesome would that be? No more long commutes to school or work.School itself will be a wholly new experience as well. Maybe we'll have artificial intelligence robot teaching assistants to help make lessons more interesting and interactive. Classrooms could have desks with built-in holographic projectors and augmented reality headsets for immersive visual learning. A lot of studies may get done at home too using virtual reality educational software. Then we could just beam in our finished assignments to the teacher over the internet!As for jobs and businesses, I'm sure a lot of new types of high-tech companies and occupations will emerge in the coming decades. We might see 3D printed food cafes that can print delicious customized meals with all your favorite flavors for you. Or superhuman cyborg workers could get hired to do the hard labor jobs that are too dangerous for regular people. There could be entire malls filled with crazy virtual reality gaming centers toowhere you get to experience being in fantastical worlds that feel 100% real!Of course, the future won't just be about new types of technology - I bet a lot of other aspects of my hometown will evolve and modernize as well. The hospitals may have super advanced robotic surgeons and nanotechnology treatments that can detect and repair damaged cells before you even get sick. Our police and firefighters will probably have access to high-tech gadgets straight out of sci-fi movies to help keep people safe. Farms could go almost fully automated with fleets ofcrop-tending robots and AI-optimized hydroponic growing facilities.We might even colonize other planets one day! Then I could look way out into space and see human cities on Mars or the Moon. Space tourism for regular families like mine could be an affordable vacation option by then too if companies like SpaceX keep making spaceflight cheaper. I'd love to visit futuristic space hotels and have views looking back at the Earth!No matter what incredible changes and innovations the future may hold though, I hope my hometown won't lose its original character and charm that I love so much. While progress is inevitable, I'll always want it to keep that welcomingsmall-town feel where everybody knows and looks out for each other. As long as that core spirit of community remains at its heart, then I'll be happy to see my little corner of the world keep evolving with the times. The future is surely full of unknowns, but I can't wait to experience it all! Who knows what wonders tomorrow will bring?。
Geometric ModelingGeometric modeling is a fundamental concept in computer graphics and design, playing a crucial role in various industries such as architecture, engineering, and entertainment. It involves creating digital representations of physical objects or environments using mathematical and computational techniques. Geometric modeling allows designers and engineers to visualize, analyze, and manipulate complex shapes and structures, leading to the development of innovative products and solutions. However, it also presents several challenges and limitations that need to be addressed to ensure its effectiveness and efficiency. One of the key challenges in geometric modeling is the accurate representation of real-world objects and environments. This requires the use of advanced mathematical algorithms and computational methods to capture the intricate details and complexities of physical entities. For example, creating a realistic 3D model of a human face or a natural landscape involves precise measurements, surface calculations, and texture mapping to achieve a lifelike appearance. This level of accuracy is essential in industries such as animation, virtual reality, and simulation, where visual realism is critical for creating immersive experiences. Another challenge in geometric modeling is the efficient manipulation and editing of geometric shapes. Designers and engineers often need to modify existing models or create new ones to meet specific requirements or constraints. This process can be time-consuming and labor-intensive, especially when dealing with large-scale or highly detailed models. As a result, there is a constant demand for more intuitive and user-friendly modeling tools that streamline the design process and enhance productivity. Additionally, the interoperability of geometric models across different software platforms and systems is a persistent issue that hinders seamless collaboration and data exchange. Moreover, geometric modeling also faces challenges in terms of computational resources and performance. Generating and rendering complex 3D models requires significant computing power and memory, which can limit the scalability and accessibility of geometric modeling applications. High-resolution models with intricate geometries may strain hardware capabilities and lead to slow processing times, making it difficult for designers and engineers to work efficiently. This is particularly relevant in industries such as gamingand virtual reality, where real-time rendering and interactive simulations are essential for delivering engaging and immersive experiences. Despite these challenges, geometric modeling continues to evolve and advance through technological innovations and research efforts. The development of advanced modeling techniques such as parametric modeling, procedural modeling, and non-uniform rational B-spline (NURBS) modeling has significantly improved the accuracy and flexibility of geometric representations. These techniques enable designersand engineers to create complex shapes and surfaces with greater precision and control, paving the way for more sophisticated and realistic virtual environments. Furthermore, the integration of geometric modeling with other disciplines such as physics-based simulation, material science, and machine learning has expanded its capabilities and applications. This interdisciplinary approach allows for the creation of interactive and dynamic models that accurately simulate physical behaviors and interactions, leading to more realistic and immersive experiences. For example, in the field of architecture and construction, geometric modeling combined with structural analysis and environmental simulation enables the design and evaluation of sustainable and resilient buildings and infrastructure. In conclusion, while geometric modeling presents several challenges and limitations, it remains an indispensable tool for innovation and creativity in various industries. The ongoing advancements in geometric modeling techniques and technologies continue to push the boundaries of what is possible, enabling designers and engineers to create increasingly realistic and complex digital representations of the physical world. As computational power and software capabilities continue to improve, the future of geometric modeling holds great promise for revolutionizing the way we design, visualize, and interact with the world around us.。
邀请科技展览Dear Friends,I am thrilled to invite you to an upcoming event that promises to be both exciting and enlightening–the inaugural Tech Expo,a gathering of the latest scientific advancements and technological wonders.In today's rapidly advancing world,the role of technology in our lives is becoming increasingly significant.The Tech Expo aims to bring together the brightest minds and innovative technologies to showcase the latest advancements in science, engineering,and mathematics.It serves as a platform to educate, inspire,and connect people with the wonders of technology.Prepare to be amazed as you navigate through a maze of interactive displays and experiences.From cutting-edge robots performing complex tasks to virtual reality simulations that take you to distant galaxies,the Expo offers something for everyone. Innovative devices the latest in technology,while scientific experiments demonstrate the principles of physics,chemistry, and biology.Interactive games allow visitors to have fun while learning about complex scientific concepts.To maximize your experience at the Expo,we recommend that you arrive early to avoid the crowds.Bring a notebook and pen to jot down interesting facts and ideas that strike you.Don't be afraid to ask questions;the exhibitors are eager to share their knowledge.Take your time to explore each exhibit;don't rush through the event.Enjoy the atmosphere and make the most of this unique opportunity to engage with science and technology.By attending the Tech Expo,you not only have the chance to witness the latest technological advancements but also to understand how these advancements are shaping our world. Such events are crucial in raising public awareness about the importance of science,technology,engineering,and mathematics (STEM)fields.They foster a culture of curiosity and exploration, encouraging the next generation of innovators.We expect theExpo to spark countless ideas,inspire countless minds,and lay the foundation for future technological breakthroughs.In conclusion,the Tech Expo is an unmissable event that promises to be both exciting and educational.Join us as we celebrate the wonders of technology and explore the limitless possibilities of the future.We look forward to seeing you at the Expo and to sharing this incredible journey of discovery with you.Warm regards,[Your Name]。
Ultraleap TouchFreeUltraleap 3Di is part of Ultraleap’s TouchFreeend-to-end solution – camera hardware, reliablehand tracking software, and developer tooling.The camera uses Ultraleap’s patented stereoinfrared technology and world-leading Geminihand tracking software. It is robust even inchallenging lighting conditions, and reliablytracks a wide variety of hand sizes and shapes.Ultraleap also provides a suite of developer toolsfor development of touchless experiences:• TouchFree Application:Detects a user’s hand in mid-air andconverts it to an on-screen cursor.Retrofit existing touchscreen interfaceswith touchless gesture control or evaluateusing your desktop monitor.• TouchFree Tooling for Web or Unity:Add touchless cursor control into kioskapplications in minutes, and have totalcontrol over how your application reactsto users’ hand movements. The Ultraleap 3Di Stereo Hand Tracking Camera isdesigned to be connected to an interactive screen.Together with Ultraleap’s world-leading software, ittransforms displays into touchless, three-dimensional,immersive surfaces.Ultraleap 3Di allows easy integration of Ultraleaphand tracking in a form factor ruggedized for use inpermanent settings – such as self-serve kiosks, digitalout-of-home installations, interactive displays in retail,museums, and theme parks, or medical/industrial uses.3DiStereo Hand Tracking CameraSimulation of Ultraleap 3Di tracking range when connected abovea 42” screen.Reverse of Ultraleap 3Di.Front of Ultraleap 3Di.SpecificationsUltraleap reserves the right to update or modify this specification without notice.Device dimensionsAll dimensions in mmw/https://e/******************o/UK: +44 117 325 9002o/US: +1 650 600 9916 UL-005619-DS - 3Di Datasheet (Issue 10)MountingUltraleap 3Di is designed to be integrated directly into permanent installations. Provided with the camera inthe product box is a Multi Mount. This mount holds the camera to the kiosk or screen and provides optimum camera placement. It can also sit on any horizontal surface to support desktop evaluation or deployments.Detailed guidelines on camera placement, mounting options, TouchFree software setup and designing for touchless experiences can be found on https:///touchfree-user-manual/.Multi Mount and Ultraleap 3Di.。
南京林业大学艺术设计学院 汤箬梅 李俊杰*引言自闭症是一种发育障碍性疾病，研究表明，儿童自闭症发病率占我国各类精神疾病首位，并且已成为当今最普遍的发展性障碍疾病之一，我国自闭症儿童超200万，而且这种趋势仍在上升。
患儿常会出现行为异常，心理障碍，缺少社会交往能力等症状。
随着自闭症康复医疗水平的进步，科学、舒适的康复空间设计能够对患儿的感官系统、心理生理健康、情感发展、社会交流的治疗起着积极作用，提升患儿的康复效果。
但目前我国多数儿童康复空间的设计仍停留在鲜艳的色彩和图案上，功能简单、造型单一，并未充分考虑自闭症儿童的实际需求。
感官统合理论是通过大脑感知环境，进而刺激感官系统的过程，这一过程对患儿的康复会起到积极作用。
本研究依据感官统合理论及自闭症儿童的心理生理特征，探索自闭症儿童康复空间新的设计模式，提升空间的整体康复效果。
一、感官统合理论基本原理感觉统合理论是由美国心理学博士爱尔丝于1969年系统提出的。
其原理是大脑和身体相互协调运作的学习过程，感觉统合是人体将不同的感觉通路（听觉、味觉、嗅觉、触觉、视觉、前庭觉和本体觉等）从环境中获取的感觉信息组合起来输入大脑，大脑对获取信息进行加工处理，处理过程包括筛选、解释、比较、抑制、联系、统一等，进而做出适应性反应的能力，简称“感统”。
感官统合的发展会影响儿童的身体健康、日常行为表现、儿童情绪智力等，儿童的各项发展都是以感官统合为基础的，若儿童的感官统合能力存在障碍，会导致儿童无法融入集体，给儿童生理和心理健康造成影响。
研究表明，基于感官统合理论下的环境设计会对儿童的感官系统产生积极的影响，能够促使大脑产生或抑制神经化学物质的分泌，可以帮助患者感官统合能力的发展，从而促进患者康复，如图1[1]。
摘要：旨在运用感官统合理论介入自闭症儿童康复空间设计，根据儿童的感官体验，营造出易于自闭症儿童康复的空间环境。
文章从自闭症儿童的内在特征出发，通过介入感官统合理论，构建情节丰富的游戏场所，营造亲近自然的景观环境，创造寓教于乐的教育空间，搭建安全舒心的康复场地等设计策略刺激儿童的感官系统，提出有利于自闭症儿童康复的空间模式。
When introducing a club in an English essay,it is essential to provide a comprehensive overview that captures the essence of the club,its activities,membership, and the benefits it offers.Heres a structured approach to writing such an essay:Title:A Glimpse into Our Vibrant ClubIntroduction:Begin by setting the context and introducing the club.Mention its name,the year it was founded,and its general purpose.Established in2005,the Vibrant Minds Club has been a cornerstone of our community, fostering a space for intellectual and social growth.Objectives and Values:Explain the clubs mission,vision,and the values it upholds.This will give readers an insight into the clubs ethos.Our club is dedicated to promoting lifelong learning,community engagement,and the exchange of diverse ideas.We believe in the power of collective wisdom and the importance of inclusivity.Membership:Describe who can join the club,the benefits of membership,and any requirements for joining.Membership is open to anyone with a passion for knowledge and a desire to contribute to our vibrant community.Members enjoy access to a range of resources,networking opportunities,and exclusive events.Activities and Events:Detail the types of activities and events the club organizes.This could include workshops, seminars,social gatherings,or community service projects.We regularly host workshops on various topics,from technology and arts to environmental conservation.Our annual Vibrant Minds Fair is a highlight,bringing together experts and enthusiasts for a day of learning and celebration.Club Structure:Outline the organizational structure of the club,including any committees,roles,and responsibilities.The club is led by an executive committee consisting of a president,vicepresident, secretary,and treasurer,all elected by the members.Subcommittees focus on specific areas such as event planning,membership outreach,and educational resources.Impact and Achievements:Discuss the impact the club has had on its members and the community.Highlight any notable achievements or recognitions.Over the years,our club has made a significant impact,inspiring members to pursue further education and engage in community projects.We have been recognized for our contributions to local education initiatives and environmental awareness campaigns.Conclusion:End the essay by summarizing the key points and inviting potential members to join the club.The Vibrant Minds Club is more than just an organization its a community of curious and committed individuals.We warmly invite anyone who shares our passion for learning and community to become a part of our journey.Call to Action:Provide contact information or next steps for those interested in joining or learning more about the club.For more information or to become a member,please visit our website or contact us at email protected We look forward to welcoming you to our vibrant community. Remember to maintain a formal yet engaging tone throughout the essay,and ensure that the content is wellorganized and easy to follow.。
Stress is an inevitable part of modern life,affecting individuals in various ways and to varying degrees.It can arise from numerous sources,such as work,school, relationships,and financial concerns.Here,we will explore the nature of stress,its potential impacts on individuals,and strategies for managing it effectively.Understanding StressStress is a natural response to a perceived threat or challenge.It is the bodys way of preparing for action,often referred to as the fight or flight response.When faced with stress,the body releases hormones such as adrenaline and cortisol,which increase heart rate,blood pressure,and energy levels.While stress can be beneficial in short bursts, chronic stress can lead to a range of health issues.Sources of Stress1.WorkRelated Stress:Deadlines,workload,and job insecurity are common stressors in the workplace.2.Academic Pressure:Students often face stress due to exams,assignments,and the pressure to perform well.3.Financial Worries:Economic instability and the burden of debt can cause significant stress.4.Relationship Strains:Conflicts with family,friends,or romantic partners can be a source of emotional stress.5.Health Concerns:Dealing with illness or the health of loved ones can be a major stressor.Effects of StressProlonged exposure to stress can have detrimental effects on both physical and mental health.It can lead to:Physical Symptoms:headaches,muscle tension,fatigue,and a weakened immune system. Mental Health Issues:anxiety,depression,and sleep disturbances.Behavioral Changes:increased irritability,social withdrawal,and substance abuse.Managing StressEffective stress management is crucial for maintaining overall wellbeing.Some strategies include:1.Time Management:Prioritizing tasks and setting realistic goals can reduce workrelated stress.2.Physical Activity:Regular exercise is known to release endorphins,which can help alleviate stress.3.Mindfulness and Relaxation Techniques:Practices such as meditation,deep breathing, and yoga can promote a sense of calm.4.Social Support:Connecting with friends and family can provide emotional support and help share the burden of stress.5.Professional Help:Seeking help from a therapist or counselor can be beneficial for those struggling with chronic stress.ConclusionWhile stress is a natural part of life,it is essential to recognize its signs and take proactive steps to manage it.By adopting healthy habits,seeking support,and maintaining a balanced lifestyle,individuals can mitigate the negative effects of stress and improve their overall quality of life.Remember,its not about eliminating stress entirely but learning to cope with it in a healthy and productive manner.。
Ⅰ.阅读单词——会意1．artificial adj.人造的，人工的2．artificial intelligence人工智能3．susceptible adj.易受影响的4．automation n．自动化5．leap n．剧变6．horizon n．地平线7．reckon v．认为，以为8．cell n．细胞9．crater n．(物体坠落、炸弹爆炸等在地上造成的)坑10．agile adj.敏捷的，灵活的11．slope v．倾斜，成斜坡12．hop n．跳跃13．squeak v．发出吱吱声14．tendon n．腱15．wavelength n．波长16．mutt n．杂种狗17．frown v．皱眉18．positronic adj.正电子的Ⅱ.重点单词——记形1．victim n．受害者2．client n．客户，客人，顾客3．cite v．引用，引述4．bound adj.可能的5．mechanical adj.机械的6．desperate adj.拼命的，绝望的7．clue n．线索，提示Ⅲ.拓展单词——悉变1．humanity n．人类→human n．人adj.人的；有人情味的2．assistant n．助手，助理→assist v．帮助→assistance n．帮助3．potentially ad v.潜在地→potential adj.潜在的；可能的n．潜力4．capacity n．能力，才能；容量→capable adj.有能力的；能干的5．analyse v．分析→analysis n．分析6．regulate v．控制，管理→regulation n．规章制度，规则7．illegal adj.非法的，违法的→legal adj.合法的8．immoral adj.不道德的，道德败坏的→moral adj.道德的9．assess v．评价，评定→assessment n．评价；评估10．cycle n．自行车v．骑自行车→cyclist n．骑自行车的人11．demand n．& v．需要，需求→demanding adj.要求高的；苛求的12．tightly ad v.紧紧地→tight adj.紧的→tighten v．(使)变紧；加强13．faulty adj.有故障的，有缺陷的→fault n．缺陷；过错14．consistent adj.一贯的，一致的→consist v．由……组成；在于1．cautious /'kɔːʃəs/adj.小心的；谨慎的→caution /'kɔːʃn/n．谨慎；小心2．comply /kəm'pla I/v i.遵守；服从comply with遵从；服从3．abundance /ə'bʌndəns/n．大量；丰盛；充裕4．viable /'va Iəbl/adj.可实施的；切实可行的5．bypass /'ba I pɑːs/v t.避开；绕过n．旁道；小路6．pledge /pledʒ/v t.保证给予；正式承诺；发誓n．誓约；捐款承诺7．controversy /'kɒntrəvɜːsi；kən'trɒvəsi/n．争论；争议8．flawless /'flɔːləs/adj.完美的；无瑕的9．prestigious /pre'st I dʒəs/adj.有威望的；声誉高的10．buzz /bʌz/n．喧闹；嘈杂声；嗡嗡声v i.发出嗡嗡声；充满兴奋；闹哄哄Ⅳ.背核心短语1．bank on依靠，指望2．on the horizon将要发生3．be bound to很有可能，肯定会4．happen to发生在……身上5．so far 迄今为止6．in contrast相反7．hang out闲逛8．be susceptible to易受……的影响9．wipe out摧毁；毁灭10．lie in 在于11．agree on就……达成一致12．go through 履行(某程序)；经历(苦难等)；完成；通过；检查；用完13．be replaced with被……取代14．change one’s mind 改变主意15．in the long run从长远来看16．around the corner很近；即将发生Ⅴ.悟经典句式1．Every recommendation she gives me is great since she can predict if I will like a particular restaurant.(since 引导原因状语从句)她给我的每一个建议都很棒，因为她能预测我是否会喜欢某家餐馆。
Unit12单词讲义vitamin词性：名词中文意思：维生素英文释义：A substance that is essential for normal growth and nutrition in animals and plants, and is required in small amounts in the diet.词源：来自拉丁语vita（生命）和amine（胺），意为“生命的胺”。
例句：Vitamin C is an important nutrient for human health.固定搭配：vitamin deficiency（维生素缺乏）、vitamin supplements（维生素补充剂）近义词：nutrient, micronutriententertainment词性：名词中文意思：娱乐，消遣英文释义：The activity of providing enjoyment or amusement, especially to an audience.词源：来自拉丁语entertainere（招待，款待），意为“招待，款待”。
例句：Watching movies is a popular form of entertainment.固定搭配：entertainment industry（娱乐产业）、live entertainment（现场娱乐）近义词：amusement, recreationinnovation词性：名词中文意思：创新，革新英文释义：The introduction of new ideas, methods, or products.词源：来自拉丁语innovare（更新，革新），意为“更新，革新”。
例句：Technology has led to many innovations in our daily lives.固定搭配：technological innovation（技术创新）、innovation strategy（创新战略）近义词：creativity, invention, improvementgifted词性：形容词中文意思：有天赋的，有才能的英文释义：Having natural ability or talent.词源：来自古英语giftan（给予），意为“赋予才能”。
Interactive Haptic Rendering of Deformable Surfaces Based on the Medial Axis Transform Jason J.Corso,Jatin Chhugani and Allison M.OkamuraThe Johns Hopkins University3400North Charles StreetBaltimore,Maryland,21218,USAjcorso,jatinch,aokamura@AbstractWe present a new method for interactive deformation and haptic rendering of viscoelastic surfaces.Objects are de-fined by a discretized Medial Axis Transform(MAT),which consists of an ordered set of circles(in2D)or spheres (in3D)whose centers are connected by a skeleton.The skeleton and physical properties of the object,including the radii of the spheres centered on the skeleton and material properties,are encapsulated in a single high dimensional parametric surface.To compute the force upon deforma-tion,we use a mass-spring-damper model that takes into account both normal and shear surface forces.Our imple-mentation attains real time3D haptic and graphic render-ing rates,making it appropriate to model deformation in complex haptic virtual environments.The algorithm is ap-pealing because it takes advantage of single-point haptic in-teraction to render efficiently while maintaining a very low memory footprint.1.IntroductionPhysical objects in the real world possess attributes far beyond those present in typical virtual reality systems.Vi-sual,haptic,aural,taste,and smell attributes are required to fully describe an object.Incorporating deformable vis-coelastic surfaces into virtual environments involves com-putationally intensive tasks.Many deformable surfaces are by nature smooth,and their visual rendering must yield an accurate representation on the display.This graphic rendering must also be per-formed at fast rates(10-20Hz).These two demands must be balanced to produce fast,but accurate graphical rendering of the surfaces.To enable real-time graphic rendering rates, specialized hardware has been developed that quickly ras-terizes triangles numbering on the order of106per frame.Triangles,however,are discrete and do not enable view-dependent adaptation for varying levels of resolution.Para-metric surfaces provide a means to render these viscoelas-tic surfaces at varying resolutions.The parametric surfaces undergo a process called tessellation during which a set of triangles are created to approximate the smooth surface;theset of triangles created is bound by either object space erroror screen space error allowing for arbitrary levels of resolu-tion.Resolved-force haptic interaction mandates an intersec-tion calculation of the user’s position with the surfaces athaptic interactive rates(1kHz).Single-point collision cal-culation with implicit surfaces involves a simple sign eval-uation of an expression describing the surfaces.However,the needs for efficient graphical rendering con-tradict those for good haptic rendering.While implicit sur-faces are superb for use in haptic rendering,their graphi-cal rendering is extremely slow.And while parametric sur-faces are the state-of-the-art in graphics rendering,employ-ing them in a haptic environment yields more complicated resolved-force calculations resulting in a slower system.Inthis work,we extend the current state-of-the-art virtual envi-ronment technology to include a new method for combinedreal-time visual and resolved-force haptic interaction with deformable surfaces.We continue this introductory section by describing the previous and related work.The algorithm for surface mod-eling is then explained in Section2.Object intersection and deformation is presented in Sections3.1and3.2.We dis-cuss our approach to haptic and graphic rendering in Sec-tions3.4and3.5.Section4describes the implementationand results.Finally,conclusions are drawn and future di-rections are listed in Section5.1.1Previous/Related WorkThe foundation of our algorithm is the use of shape skeletons as a basis for the object model.Shape skeletonsTo be presented at Eurohaptics 2002Ediburgh, UK, July 8-10, 2002Figure 1.Development of an object from the Medial Axis Transform includes:(a)the origi-nal skeleton,(b)the original skeleton with the circles/spheres,and (c)the spline approxima-tion to the skeleton and surface.are geometric abstractions of curves or surfaces that are use-ful as lower-dimensional representations.The skeleton is known in 2D as the medial axis and in 3D as the medial surface .Each point on the medial axis or surface is asso-ciated with the radius of a locally maximal disk or sphere.These medial points,together with their associated radii,de-fine the MAT of an object.An example of a 2D/3D medial axis/surface with the associated circles/spheres is shown in Figure 1.The MAT was first proposed by Blum [4]as an alternative shape description for biological applications.It has recently been used by Pizer et al.[22]as a multilo-cal and multiscale representation for graphic and computer-aided design applications,where a figure is defined by a mesh of medial “atoms.”Gagvani [9]has recently em-ployed skeletonization to automatically generate the volu-metric representation of a polygonal mesh.He explores the approach for use in volumetric modeling,deformation,and animation.Okamura et al.[19]developed a robotic sys-tem to acquire medial axis-based models of rigid surface features on real 3D objects.Their work demonstrates the usefulness of the MAT in modeling real-world objects.Finite Element Methods (FEM)and Boundary Element Methods (BEM)[11]have been used for physical represen-tation in haptic environments.FEM and BEM,while be-ing computationally and memory expensive,can accurately compute deformation and contact forces.The work of Pai et al.[12,13](called ArtDEFO)employs BEM for accurate deformation;it exploits the coherence of typical physical interaction in order to achieve interactive rates for relatively small models.FEM/BEM have been used in the medical domain for surgery simulation [3,6,17].These simulations include the ability to dynamically cut and tear the model.In the graphics community,object deformation has been successfully implemented using many types of object mod-els.However,most of these methods suffer in application to haptic rendering because they cannot provide force feed-back at interactive rates.We refer to the technical report by Gibson et al.[10]for a survey of deformable models used in computer graphics.Free-form solid deformation [5,23]is the most broad approach to modeling real solids.It has been used as an extension of Geometric Modeling to create more realistic design environments for human modelers;it separates the underlying geometry from the model as much as possible.Sensable Technologies Inc.(Woburn,MA)has developed a product called the FreeForm TM Modeling System.Its existence demonstrates an industry wide need for haptic-based modeling environments.V olumetric ap-proaches have also been taken to model deformable objects.Avila and Sobierajski [1]present a volumetric method suit-able for both visualization and modeling applications.They compute point contact forces directly from the volume data consistent with isosurface and volumetric graphic rendering methods,thereby ensuring consistency between haptic and visual feedback.In more recent work,Frisken and Perry [8]have explored the use of Adaptively Sampled Distance Fields to model soft body contact in a computationally effi-cient framework.NURBS surfaces have also been used in haptics-based applications because of their dominance in the CAD/CAM fields.Object modeled as NURBS surfaces can be rendered interactively at varying levels of resolution with bounded error [15].This makes them attractive for use in graph-ically intensive applications.Another set of algorithms [14,18,25]have been developed for direct haptic render-ing of NURBS based models,including an extension to surface-surface interaction which removes the single-point of intersection constraint commonly found in haptic render-ing.Terzopoulos and Qin [24]have developed D-NURBS,a physics based generalization of NURBS curves and sur-faces.D-NURBS are derived through the application of La-grangian mechanics and implemented using FEM.In our work,we present a novel approach that employs an extended MAT to compute haptic interaction comple-mented by the NURBS representation to render visually ap-pealing surfaces.It integrates the needs of good haptic and graphic rendering by combining a parametric skeleton en-capsulating an underlying set of implicit shapes (circles in 2D and spheres in 3D)with a parametric surface for accu-rate view-dependent graphic rendering.The salient features of our method are (1)object models are easily created using a discretized Medial Axis Transform (MAT),and the algo-rithm automatically generates a high dimensional paramet-ric surface that encapsulates object shape,stiffness,damp-ing,and mass,(2)the algorithm for collision detection and haptic feedback of normal and surface shear forces is ef-ficient,taking advantage of single-point haptic interaction,and (3)the addition of dynamic behavior is straightforwardFigure 2.This dynamically deformable3-dimensional object is haptically rendered at1kHz on a standard PC.The white dot repre-sents the location of the haptic interface inthe virtual environment.because deformation is directly calculated from object prop-erties included in the parametric surface.Our implementa-tion,DeforMAT,achieves real time rendering rates for hap-tic interaction,which are on the order of1kHz.An image of a virtual environment with a MAT object is shown in Figure 2.2.Object ModelingAn object(Figure1)consists of the following attributes: 1.The discretized medial surface(skeleton),obtained us-ing a valid MAT on the original surface of a real body.A number of algorithms[4,7,9]have been proposedwhich can extract the skeleton from the description of any given body.2.Radii of the spheres centered along the skeleton.3.Stiffness(and potentially other material properties)ofeach sphere centered along the skeleton.From the above given data,we construct the following at-tributes:1.Skeleton Spline(SK),a high dimensional Open,Non-Uniform B-Spline Surface1thatfits the position,ra-dius,and material properties associated with each skeleton point.2.Surface Contour(SC),a3D Open,Non-Uniform B-Spline Surface that is the explicit body contour.This is used only in graphic rendering.When the user interacts with bodies in the virtual environ-ment,we determine whether the user is intersecting a bodyusing the medial surface SK(Section3.1).This is followed4.For i1m and j1n:For the given point Pi j on the medial surface,compute the normal(using SKD u and SKD v),N i j .Obtain Ri j Pi jr i j Ni jand Si jPi jr i jN i j where r i j is the radius of the circle at P i j.Toensure surface continuity,r i j is assumed to beequal to zero at the end points.5.Interpolate an Open,Non-Uniform3D B-Spline Sur-face through R i j i1m j1n to obtain the sur-face for the top part of the body,and through Si j i1m j1n to obtain the surface for the bottom part of the body.These two surfaces together form the body contour,SC.3.Object Interaction3.1.Intersection ComputationWe perform an efficient intersection computation which gives us the position of the user relative to boundary of the surface within sub-pixel accuracy.2We execute a binary search over the knot value range in the two directions to de-termine the parametric values,such that the normal drawn on the skeleton spline SK passes through the point on which the user lies.Let u begin v begin and u end v end represent the two end points of the interval being examined(Figure 3).Let Q represent the position of the user.The algorithm terminates when the length of the interval(in both the direc-tions)falls below pre-defined thresholds,or when the nor-mal passes through the point Q.The algorithm returns the parameter value,say u intersect v intersect,such that the nor-mal drawn on the SK at u intersect v intersect(call this point P)would pass through Q.Now compute the distance between P and Q(PQ), and radius of the circle at u intersect v intersect(called R intersect).If(PQ R intersect then the user intersects the object,otherwise,the user is outside the object.The al-gorithm terminates in maximum of1+log212An iterative solver is not suited for real-time haptic interactions.The current implementation is only guaranteed to work for convex medial sur-faces.In practice,errors occur rarely with concave medialsurfaces.Figure3.Intersection computation involves it-eratively modifying the values of parametersu and v to obtain the point P on the spline per-pendicular to the position of the user,pointQ.For clarity,thisfigure shows only one pa-rameter,u.Figure4.Displacement of the object skeletonand contour upon contact,shown in2D. visually and apply forces on the user.Let the user be pen-etrating a distance ofδinside the boundary of the object, whereδR intersect PQTo reflect the deformation of the body,we need to change the skeleton spline(SK),including the radii of the circles in the neighborhood of the region,and the contour spline(SC) (Figure4).One can consider two schemes for body deformation. In thefirst scheme,the interaction moves the skeletal sur-face SK,and both the body surfaces follow.In the second scheme,only the body surface intersecting with the user (e.g.,the top surface)moves,while the other surface(e.g., the bottom surface)does not.To model this type of body compression,let a skeleton point be displaced by a distance of gδ,while the radii spline is displaced by1gδ.When g05,the contour of the body opposite the user is not displaced.The algorithm for displacing the splines givenδand PQ is explained later in Section3.3.In both schemes,the object can be deformed dynami-cally through the use of a second order dynamic system.This approach models organic bodies well because of their damped elastic,non-rigid nature.We imagine springs and dampers at the control points of the contour spline(SC) and skeleton spline(SK).When the user interacts with the model,these springs undergo a change in length,and an in-ternal force is felt by the control points,pulling them back towards their original positions.Dampers are added to re-duce the oscillation of the surface.The positions of the control points are evaluated using standard second order dynamic equations.Let p prev,v prev and a prev be the position,velocity and acceleration respec-tively of a control point in the previous frame.Let p neut be the original position of that control point.The current force on the control points isf k p prev p neut b v prevwhere k is the stiffness coefficient of the spring and b is the damping coefficient.The current acceleration of the con-trol point is a curr=fdt2bd x2m.Hence,the values of b,m and k are chosen so that the points come to rest in a short time.The algorithm for displacing the splines is explained in the following sec-tion.3.3.Spline DeformationHere we describe the approach we have taken to displace the control points of the body surface SC given the dis-placement vector of a point on the monly used techniques include changing the knot vector and the weights of the control points(for rational B-Splines)[20,21].The technique we use is an extension of Piegl’s control point modification scheme.Our method involves modifying the p q most influenced control points in proportion to their contribution to the contact point on the surface,and pp1,q q1,where p and q are the degrees of the surface in the u and v directions respectively.(The val-ues for p and q should be set with symmetry,such that if p is odd,then p should be even and vice versa).This guarantees a smooth change in the shape of the modified B-Spline Surface as the set of control points change with the displacement of the curve.For a better approximation, one can modify up to p1q1control points.How-ever,in practice,for a surface of degree p q,displacing p2control points gives a visually acceptable approxima-tion.In order to obtain real-time frame rates,the number of changed points should be kept to a minimum.Because deformations move multiple control points,we retessellate the entire surface at each time step.For explanation purposes,assume a2D B-Spline Curve of degree4with control points C i,i1n.A point P, having a parametric value t,has to be moved by a distance d along the vectorˆv.Say the parametric value t lies in the knot vector range t j t j1.The control points affecting any parameter value in this range are C j C j4.We choose to deform only C j1,C j2and C j3.Let the basis values for these control points be B1t,B2t and B3t.Let these control points be displaced byα1ˆv,α2ˆv andα3ˆv.Hence,dα1B1tα2B2tα3B3tAlsoα1:α2:α3=B1t:B2t:B3t.These two equations imply:C j1C j1dB1tB21t B22t B23tˆvC j3C j3dB3t2l q1q2l q q1Figure 5.Forces applied to the user upon contact are calculated from a second-order spring system.One spring,connecting the contact point to the skeleton,pushes the user in a direction normal the surface.Four springs (only two are shown in this 2D view)apply shear force from nearby points on the surface contour.k u v x ,where k u v is the stiffness value obtained from SK .(The damping b u v and mass m u v are also obtained from SK .)To model the shear forces along the surface (as a result of the strain on the contour),we consider four more spheres,at a distance δ(in parametric space in both the u and v di-rections),on either side of the point of intersection.These springs are henceforth referred to as K u δ,K u δ,K v δand K v δ.The resultant spring system in one parametric direc-tion is shown in Figure 5.A similar placement would hold for the other parametric axis.Let the displacement of the springs be x u δ,x u δ,x v δand x v δ.The stiffness val-ues of the springs are set to keq uδ=k u δv k u v2,keq v δ=k u v δk u v2.The net force f f eedback on the user is equal to k u v x keq u δx u δkeq u δx u δkeq v δx v δkeq v δx v δ.It can be shown that the force always increases as the user pen-etrates the object,and the direction of the feedback force always pushes the user out of the object.3.5.Graphic RenderingWe used the OpenGL API to display the surfaces.To render the virtual objects,we used the GLU NURBS Tes-sellator which computes the triangulation of every surface (within a user specified screen-space error),and renders these triangles to compose the final image.This tessella-tion is done every frame,with frame rates varying between 10-20frames for most of the models.We also incorporate basic view frustum culling to further speed up the rendering rates.One of the major advantages of tessellating a surface for rendering is that it exploits the fast triangle rendering capability of the hardware,thereby leading to high graphicupdate rates.It is important to note that the complexity of the virtual environment being graphically rendered is on an average about 105triangles and is independent of the num-ber of spheres because of the view-dependent adaptive tes-sellation of the NURBS surface.4.Implementation and ResultsOur system is developed in C++on a standard 700MHz Pentium III Computer with 384MB of main mem-ory.Virtual world navigation is performed using the computer mouse,and for force feedback we employ a PHANTOM TM Premium 1.53-degree-of-freedom haptic device from SensAble Technologies,Inc.(Woburn,MA).For graphics hardware,we used the NVidia GeForce2c card.The haptic device control ran in a separate high-priority thread at 1kHz.Table 1shows the performance of our algorithm with objects of varying complexity.5.Conclusion and Future WorkWe present a new algorithm for interactively deforming viscoelastic bodies at haptic interactive rates,i.e.1kHz.Our system fits a niche much needed in the virtual environ-ment arena:namely,the ability to add dynamic deforma-tions coupled with haptic feedback in a virtual environment with minimal cost.The algorithm balances the contradic-tory demands of haptic rendering with those of graphic ren-dering in a manner well suited for numerous applications,including medical simulation,art,and entertainment.One example of a medical application is a training system for tumor location using palpation.This initial implementation of our algorithm includes the minimum features required to simulate dynamic,de-formable surfaces.There exist many avenues for fu-ture work,including bifurcating and non-ordered medial axes/surfaces,analysis of area/volume preservation,imple-mentation of more efficient graphical rendering algorithms ([15,16,22]),experimentation with different deformation modes,and direct performance comparison against other methods.AcknowledgmentsWe acknowledge Samuel Khor for starting the work on haptic rendering using shape skeletons at The Johns Hop-kins,and thank Budirijanto Purnomo for his assistance with B-Spline deformation.#Preprocessing Time in Points Graphics Graphics49400KB17Hz20Hz13sec979Hz996Hz26% 213 1.8MB11Hz15Hz109sec980Hz992Hz27% 465 3.0MB9Hz12Hz3556sec980Hz990Hz36%Table1.Our algorithm’s performance for virtual environments of varying complexity.Listed are the number of bodies in the virtual environment,the total 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