2. Projection technologies

High technology,often abbreviated as hitech,refers to the most advanced technology available in a field at any given time.It is characterized by rapid innovation, significant advancements in various sectors,and a profound impact on society and the economy.Here are some key aspects of high technology that can be discussed in an English essay:rmation Technology IT:The backbone of modern high technology,IT encompasses computers,software,databases,and the internet.It has revolutionized communication,business operations,and personal lifestyles.2.Artificial Intelligence AI:AI is the simulation of human intelligence in machines that are programmed to think like humans and mimic their actions.This includes machine learning,natural language processing,and robotics.3.Biotechnology:This field combines biology and technology to create or modify organisms,cells,or biological molecules for various applications,including medicine, agriculture,and environmental science.4.Nanotechnology:The manipulation of matter on an atomic,molecular,and supramolecular scale.Nanotechnology has applications in various industries,such as electronics,medicine,and materials science.5.Renewable Energy Technologies:These include solar panels,wind turbines,and other methods of harnessing energy from natural resources without depleting them.6.Space Technology:Advancements in rocketry,satellite technology,and space exploration have opened up new frontiers for scientific research and potential colonization.7.Medical Technology:Innovations in medical technology have led to the development of advanced diagnostic tools,surgical procedures,and treatments,including telemedicine and personalized medicine.8.Transportation Technology:Highspeed trains,electric vehicles,and autonomous cars are examples of how technology is transforming the way we move from one place to another.9.Cybersecurity:With the increasing reliance on digital systems,cybersecurity has become crucial to protect data and systems from threats such as hacking and cyber attacks.cation Technology EdTech:The use of technology in education to enhance learning experiences,including online learning platforms,virtual classrooms,and educational software.11.Environmental Technology:Solutions that address environmental challenges,such as pollution control,waste management,and sustainable resource use.12.Blockchain Technology:A decentralized ledger system that allows for secure and transparent transactions without the need for intermediaries.13.Virtual Reality VR and Augmented Reality AR:These technologies create immersive experiences by simulating or enhancing the real world,with applications in gaming, education,and training.14.3D Printing:The process of creating threedimensional objects from digital models, which has applications in manufacturing,medicine,and architecture.15.Quantum Computing:A new type of computing that uses quantum bits,or qubits,to process information in ways that traditional computers cannot,potentially solving complex problems much faster.In your essay,you can explore the benefits and challenges of high technology,its impact on society,and the ethical considerations that come with its development and use. Additionally,you can discuss the future prospects of these technologies and how they might shape the world in the coming years.。

Science has been a cornerstone of human progress,driving innovation,improving lives,and expanding our understanding of the universe.The benefits of science are manifold and farreaching,touching every aspect of our daily lives.Here are some of the key advantages that science offers:1.Health Advancements:One of the most significant contributions of science is in the field of medicine.Scientific research has led to the development of vaccines,antibiotics, and advanced surgical techniques,which have saved countless lives and improved the quality of life for many.2.Technological Innovation:The digital age we live in is a testament to the power of puters,smartphones,and the internet have revolutionized communication, education,and commerce,making the world more connected than ever before.3.Environmental Sustainability:Science plays a crucial role in understanding and addressing environmental issues such as climate change,pollution,and biodiversity loss. It provides the tools and knowledge necessary to develop sustainable practices and technologies.4.Economic Growth:Scientific discoveries and technological advancements are key drivers of economic growth.They create new industries,jobs,and opportunities for wealth generation,contributing to the overall prosperity of societies.cation and Knowledge:Science education is fundamental to developing a wellinformed and skilled workforce.It fosters critical thinking,problemsolving skills, and a deeper understanding of the world,which are essential for personal and societal development.6.Space Exploration:The exploration of space has been made possible through the application of scientific principles.It has not only expanded our knowledge of the cosmos but also led to the development of technologies that have practical applications on Earth.7.Agriculture and Food Security:Science has transformed agriculture,increasing crop yields and ensuring food security through genetically modified crops,improved irrigation systems,and sustainable farming practices.8.Disaster Prevention and Response:Scientific research helps in predicting natural disasters such as earthquakes,hurricanes,and tsunamis,allowing for better preparedness and response strategies to minimize loss of life and property.9.Social Progress:Science contributes to social progress by challenging and changing societal norms and beliefs.It promotes evidencebased decisionmaking and helps to debunk myths and superstitions.10.Cultural Understanding:The study of anthropology and archaeology,which are scientific disciplines,has enriched our understanding of human history and cultural diversity,fostering a greater appreciation for different cultures and traditions.In conclusion,the benefits of science are vast and varied,impacting every facet of human existence.It is a driving force for positive change and a key to unlocking the mysteries of our world.As we continue to push the boundaries of knowledge,the potential for science to improve our lives only grows.。

REGULAR PAPERAn interactive handheld spherical 3D object display systemZhaorong Li •Kin-Hong Wong •Man-Chuen Leung •Hoi-Fung Ko •Kai-Ki Lee •Michael Ming-Yuen ChangReceived:13May 2010/Accepted:27January 2011/Published online:16February 2011ÓSpringer-Verlag 2011Abstract Traditional display systems usually display 3D objects on static screens (monitor,wall,etc.)and the manipulation of virtual objects by the viewer is usually achieved via indirect tools such as keyboard or mouse.It would be more natural and direct if we display the object onto a handheld surface and manipulate it with our hands as if we were holding the real 3D object.In this paper,we propose a prototype system by projecting the object onto a handheld foam sphere.The aim is to develop an interactive 3D object manipulation and exhibition tool without the viewer having to wear spectacles.In our system,the viewer holds the sphere with his hands and moves it freely.Meanwhile we project well-tailored images onto the sphereto follow its motion,giving the viewer a virtual perception as if the object were sitting inside the sphere and being moved by the viewer.The design goal is to develop a low-cost ,real-time ,and interactive 3D display tool.An off-the-shelf projector-camera pair is first calibrated via a simple but efficient algorithm.Vision-based methods are proposed to detect the sphere and track its subsequent motion.The projection image is generated based on the projective geometry among the projector,sphere,camera and the viewer.We describe how to allocate the view spot and warp the projection image.We also present the result and the performance evaluation of the system.Keywords 3D interactive display ÁProjector-camera system ÁObject tracking ÁVirtual and augmented reality1IntroductionTraditional 2D display systems usually display 3D objects on static screens and the viewer interacts with it using indirect input devices such as keyboard or mouse.It is unnatural and the perceived level of reality is low.A projector is a good choice to improve the freedom and interactive ability of these systems,but nearly all existing systems can only display 2D information.Technologies using polarized light are popular to create 3D perception by 2D monitors,but they require the viewer to wear specially designed spectacles.Another approach is motion parallax in which the viewer can perceive 3D information when the display is moving.This can be achieved by projectors and motion sensors.We propose that we can use motion par-allax to create a direct 3D virtual object manipulation tool based on computer vision and several off-the-shelf devices.This paper presents a prototype system in which we displayCommunicated by Baochun Li.Electronic supplementary material The online version of this article (doi:10.1007/s00530-011-0228-y )contains supplementary material,which is available to authorized users.Z.Li ÁK.-H.Wong (&)ÁM.-C.Leung ÁH.-F.Ko Department of Computer Science and Engineering,The Chinese University of Hong Kong,Shatin,Hong Kong e-mail:khwong@.hk Z.Lie-mail:zrli@.hk M.-C.Leunge-mail:mcleung@.hk H.-F.Koe-mail:hfko@.hkK.-K.Lee ÁM.M.-Y.ChangDepartment of Information Engineering,The Chinese University of Hong Kong,Shatin,Hong Kong e-mail:kklee6@.hk M.M.-Y.Change-mail:mchang@.hkMultimedia Systems (2011)17:435–447DOI 10.1007/s00530-011-0228-ythe3D object onto a handheld sphere and manipulate it with our hands directly as we do in our daily lives.The proposed systemfinds many applications in real life.For instance,in a museum mounted with many pro-jectors,the visitor can use this handheld display tool to explore the computer-generated copy of the historical artifact which is not available to the visitor for touching. This gives the visitor a realistic feeling about the artifact and direct manipulation of it while the real object is pro-tected from damage.Likewise,manufacturers can also use this tool to promote a new product when it is still in the design stage and a real product is not yet available.The3D perception and direct manipulation interface can definitely give the viewer a better feeling about the product.The objective of our work is to build a low-cost,easy-to-build and workable3D object manipulation tool without requiring the viewer to wear spectacles.Instead of using magnetic sensors or specially designed hardware,we use several low-cost,off-the-shelf devices and computer vision technologies to build the system.The main idea of the system is to use a handheld sphere as the projection sur-face.When the viewer moves and rotates the sphere,we use object tracking techniques to track the translation and rotation of the sphere.Meanwhile,based on the pre-cali-brated projective geometry among the camera,sphere,projector and the viewer,we project well-tailored images of the object onto the sphere depending on its translation and rotation.By continuously adjusting the images pro-jected to the sphere as it moves and rotates,the motion parallax gives the viewer a virtual3D perception as if the object were sitting inside the sphere and being manipulated by the user directly.The devices used in our system include a projector,a webcam,a Nintendo Wiimote and a foam sphere.The consideration for choosing a sphere as the projection surface is its symmetry in shape.Moreover,to adapt to different application scenarios,we design two kinds of configurations to track the sphere.In thefirst configuration,we embed four IR LEDs on the surface of the sphere and use the Nintendo Wiimote(which has a PixArt IR camera embedded inside)to track their positions. In the second configuration,the sphere is encompassed with a cardboard.By tracking the cardboard,we can also obtain the motion of the sphere.In Fig.1a,we show the whole diagram of our system.The camera,projector and Wiimote arefixed on a rig,as shown in Fig.1b.The two configurations of the sphere are also shown in Fig.1b.The development of the whole system faces many challenges in various computer vision and graphicfields, including projective geometry,projector-camera calibra-tion,object tracking,and spherical display.Our main contribution is the proposal of a new type of display system and the realization of it through the integration of various technologies and devices.The remainder of the paper presents how we handle these challenges.It is organized as follows:Sect.2discusses some related work.Section3 gives the overview of the system.Section4describes the calibration of the projector-camera pair.In Sect.5,we introduce how to track the translation and rotation of the sphere.Section6describes how to generate the projection image correctly.The implementation details and results are given in Sect.7.We conclude the paper in Sect.8.2Related workProjector-based display system is not new.It is popular in augmented reality(AR)and human computer interaction (HCI)since such systems improve the freedom of the display and provide easy ways of man machine interaction. In this section,a review over existing projector-based systems is presented.Especially,two types of systems closely related to our proposed research,non-planar-sur-face systems and movable-surface systems,are discussed in more detail.2.1Projector camera systemIn the literature,numerous projector camera systems have been developed to create many kinds of applications.One popular application is to use multiple projectors to build large display walls for creating immersiveenvironment. Fig.1The configuration of our system:a the overall diagram of our system;b the projector,camera and Wiimotefixed on the rig;the foam sphere with four IR LEDs embedded on the surface;another foam sphere encompassed with a cardboard436Z.Li et al.The CAVE system[1]uses three rear projectors to project onto three walls of a cube-shaped room and one facing down projector to project onto thefloor,creating a fully immersive virtual reality environment.The Teleport sys-tem[2]uses a projected wall to create the illusion of extending the room to another one for a teleconferencing system.Projection technologies are also used to modify the appearance of a real object or an environment.The Shader Lamp[3]explores the use of projection light to alter the appearance of a complex3D object.The ability of con-trolling the appearance of an object enables applications such as simulating a real scene[4],or making one object look like another[5].In most of these applications,the projector and screen are atfixed positions,and a planer screen is usually used.In order to create the correct projection,projector-based systems require various calibration processes,including geometric calibration,photometric calibration,etc.Since the projector cannot observe the projection result,a camera is usually included as a visual feedback in the calibration. For a planar screen,the geometric relationships among the projector,camera and screen can be represented by a couple of393homographies,which can be estimated via the correspondences among them.For example,Sukthan-kar et al.[6]proposed a smart presentation system in which they estimated the projector-to-camera homography via projecting known patterns to the screen and estimated the screen-to-camera homography via detecting the boundary of the screen.An auto-calibration algorithm without detecting the screen boundary or using markers on the screen is also proposed[7].Another explicit calibration algorithm[8]can estimate all parameters including intrinsic parameters of the projector and the relative pose between the projector and camera.However,these two methods are complicated.In multiple projector systems, the calibration further requires estimating the relationship among the projectors[9].Moreover,in order to stitch multiple projection images from different projectors,pho-tometric calibration is also needed.Detailed discussion can be found in[10,11].2.2Non-planar display surfaceNon-planar display surfaces are mainly employed in two kinds of applications.One is for arbitrary surface display. For example,Kondo et al.[12]proposed a free form pro-jection display(FFPD)system for displaying images on arbitrarily shaped surfaces.By scanning the3D structure of the surface with a3D scanner,they can display3D content onto the surface without distortion.Another kind of application is for large-scale immersive display which gives the viewer an immersive experience and more free-dom of view.Multiple projectors and cameras are included in such systems in order to cover a larger portion of the surface.For example,Raskar et al.[13,14]proposed a scalable panoramic display system with multiple casually positioned projectors.The geometric calibration of the projector-camera pair with curved surface is more com-plicated since their relationship is no longer a planar homography.In[14],Raskar et al.proposed a parametric approach called quadric transfer to represent the relation-ship for quadric surface.We do not employ this method in our system but adopt another approach(detailed in Sect.3) since the sphere used in our system is movable and the proposed method is simpler and more efficient in locating points on the movable spherical surface.2.3Movable surfaceMobility is being given more and more attention in the development of projector camera systems.With a movable screen,more interaction can be introduced to enrich the user experience.The success of a movable-surface system relies on reliably tracking of the surface.In existing sys-tems,two categories of tracking mechanisms are most frequently used.One is based on magnetic sensors or specially designed tracking devices.For example,the Dynamic Shader Lamp[15]extends the Shader Lamp[3] to allow users to hold the object in hands by adding a six degree optical tracker and a magnetic tracker.Though good tracking accuracy and robustness can be achieved,the tracking sensors are expensive and also limited to certain environments.On the other hand,computer vision tech-nology is usually employed to track regular surfaces.Since a camera is often included to calibrate the projector,it is natural to use it to track the display surface without including extra cameras.Therefore,many existing systems use vision-based tracking methods.The Portable Display Screen(PDS)system[16]detects and tracks a cardboard with black borders using Hough transform and Kalman filter.The Active Pursuit Tracking system[17]attaches four-colorfiducials to a white cardboard and tracks them using Camshift algorithm.Leung et al.[18]proposed a particlefilter algorithm to track a white cardboard based on edge features.The major advantage of using a vision-based tracker over sensor-based tracker is its low cost,though the tracking accuracy and robustness may be not very high. Since low cost is one design goal of our system,we track the motion of the movable based on vision algorithms as long as satisfactory robustness and accuracy are achieved. 3System overviewOur system is an integration of three major modules,the calibration module,the tracking module,and the projectionAn interactive handheld spherical3D object display system437module.The calibration module is an offline module,which finds the relationship among the projector,the camera and the Wiimote.The tracking module takes the live capture from the camera as input,and tracks the translation and rotation of the sphere relative to the camera for each frame.Based on the calibration result and the tracked motion of the sphere,the projection module generates the projection image of the displaying object and projects it onto the sphere.The workflow of the system and the interaction between different modules are shown in Fig.2.In following sections,we describe each module in detail:4System calibrationIn the calibration stage,we calibrate two geometric rela-tionships,one between the projector and the camera andthe other between the Wiimote and the camera.The target of calibrating the projector camera pair is to align the projector with the camera,while the calibration of the Wiimote camera pair is for tracking the IR LEDs on the sphere.Previous calibration methods applied to planar surfaces and static systems are no longer applicable due to the movable nature of the spherical surface we used.In our approach,without the need to know explicit geometric parameters,we simply estimate two projection matrices,one from the camera coordinate system to the projector image plane and another from the Wiimote coordinate system to the camera image plane.Both projection matri-ces are constant and independent from the movement of the sphere.This makes our calibration fairly easy.A simple calibration algorithm is proposed.The basic idea is to use the sphere as the calibration object.By manually labeling anumber of corresponding points on the sphere in the pro-jector and camera (or Wiimote and camera)images,we can estimate the projection matrices.4.1The projective modelThe ideal projection model of the projector is the same as that of the camera except for the projection direction.The projection from a 3D point to the 2D projector image pixel is also via a 394perspective projection matrix.Then any 3D point in the camera coordinate system,for example,a point X c ðx ;y ;z Þon the sphere,corresponds to its projector pixel x p ðu ;v Þvia a projection matrix M c p :s ~x p ¼M c p ~X cð1ÞandM cp ¼m 11m 12m 13m 14m 21m 22m 23m 24m 31m 32m 33m 34@1A ð2Þwhere ~x p ;~Xcare the homogenous coordinates and s is a scale factor.The Wiimote has a PixArt IR camera embedded inside which is able to track IR LEDs.So the projective model of the Wiimote can also be represented by a 394projection matrix.Then any 3D point in the Wiimote coordinate system,for example,an IR LED L w ðx ;y ;z Þon the sphere,corresponds to its projection in the camera l c ðu ;v Þvia a projection matrix M w c :s ~l c¼M w c~L w ð3ÞThe task of calibration is then subjected to estimatingtwo projection matrices M c p and M wc .trackingprojectionc projectioncapture3D objectmodel to 438Z.Li et al.4.2Calibration of the projector camera pairThe projective geometry between the projector camera pair is shown in Fig.3.The light from some pixel x pðu;vÞin the projector image intersects the sphere at X cðx;y;zÞ(in camera coordinate system),and then creates pixel x cðu;vÞin the camera.These three pointsðx p;X c;x cÞform a cor-respondence.The basic idea of estimating the projection matrix is to collect a number of such correspondences.A correspondence is collected in the following way:we project a cross at known position onto the surface of the sphere and observe the cross using the camera.For each correspondence,the2D coordinates of the point in the camera x c can be manually labeled while the3D coordi-nates of the point on the sphere surface X c cannot be directly obtained.In order to calculate X c,we need to locate the3D position of the center of the sphere in the camera coordinate systemfirst.The3D position of the center of the sphere can be located based on its projection in the camera.According to [19],the projection of a sphere is a conic section under the pinhole perspective camera model.Since the depth infor-mation is lost in perspective projection,the conic section could be created by a family of center-collinear spheres. Given only the conic section,we cannot uniquely recognize the actual sphere out of the family.However,once the physical radius of the sphere is given,the sphere can be uniquely located.We use the geometric method proposed in[20]to locate the center of the sphere.The basic idea of the method is to investigate the relationship between the general case where the sphere lies at an arbitrary position and the special case where the sphere lies on the z axis of the camera.In the special case,the image of the sphere is a circle and the center of the sphere can be easily located given the circle.The sphere at arbitrary position can be viewed as rotated from a sphere on the z axis.Accordingly, the image of the sphere changes from a circle to a conic section due to the rotation.So given the conic section C and the radius of the sphere R,wefirst locate the center of the sphere(0,0,d)in the special case and rotate it to the actual position S c.This is illustrated in Fig.4.In our implementation,we use the Hough transform circle detection algorithm to detect a circle to approximate the conic section.After the center of the sphere is located,we can calcu-late the corresponding point on the surface of the sphere for each pixel within the conic section.For each correspon-denceðx p;X c;x cÞ;the point X c on the surface of the sphere in camera coordinate system should satisfy the following equations:s~x c¼K c X cX cÀS ck k22¼R2ð4Þwhere K c is the intrinsic parameter matrix of the camera which is calibrated beforehand using the OpenCV toolbox [21].Thefirst equation is the projection equation,and the second is to constrain the distance between the surface point and the sphere center.We solve them to obtain X c for each correspondence.Now for each calculated correspondence,we can write a projection equation according to(1)and(2):suv1@1A¼m11m12m13m14m21m22m23m24m31m32m33m34@1Axyz1B B@1C CAð5ÞWe rewrite it in the equivalent form by eliminating the scale factor:u¼m11xþm12yþm13zþm14m31xþm32yþm33zþm34v¼m21xþm22yþm23zþm24m31xþm32yþm33zþm34ð6ÞIt can be further rearranged in the following form:xm11þym12þzm13þm14Àuxm31Àuym32Àuzm33Àum34¼0xm21þym22þzm23þm24Àvxm31Àvym32Àvzm33Àvm34¼0ð7ÞAn interactive handheld spherical3D object display system439Assuming that we have collected totally ncorrespondences,ðx pi ;X ci;x ciÞ;i¼1...;n;we rearrangeall the equations to a linear system of the form Gm¼0; where G is a2n912matrix,m is a1291vector arrangement of the rows of the projection matrix to estimate.There are totally12variables,so n C6 correspondences are enough to solve it.We obtain a solution which introduces the least error using singular value decomposition(SVD).Moreover,in order to compensate labeling errors and obtain a stable solution, we take following steps:first,we use a RANSAC scheme in our algorithm.For each run of RANSAC,we randomly select six correspondences to estimate the projection.The criterion for admitting an inlier is that its back-projection error is below ten pixels.Second,afine adjustment is carried out on the RANSAC result.It minimizes the following sum of the squared back-projection errors:X n i¼1u iÀm11x iþm12y iþm13z iþm14m31x iþm32y iþm33z iþm34 2þv iÀm21x iþm22y iþm23z iþm24 m31x iþm32y iþm33z iþm342ð8ÞTaking the RANSAC solution as the initialization,we use the Levenberg–Marquardt algorithm[25]to minimize the error.With these strategies,the accuracy of the estimated projection matrix is further improved.4.3Calibration of the Wiimote camera pairThe calibration of the projection matrix M w c can be done in a similar way.First,we calibrate the intrinsic parameters of the Wiimote.Since the four IR LEDs can be viewed as four corners of a calibration board,we can also use the OpenCV toolbox to calibrate the intrinsic parameters of the Wii-mote.Second,according to the projective geometry in Fig.3,each IR LED on the sphere L c;its position in the Wiimote l w and its position in the camera l c;form a cor-respondence.To collect a number of correspondences,we place the sphere to different positions within the common field of view of the camera and Wiimote.Four corre-spondences can be obtained at each position.The locations of the IR LEDs in the Wiimote images can be directly detected by the Wiimote and their positions in the camera images are manually labeled.Their3D coordinates in the Wiimote coordinate system are calculated by a Perspective 4Points(P4P)algorithm given the configuration of the four IR LEDs and the intrinsic parameters of the Wiimote.In our implementation,the P4P algorithm proposed by Zhang [22]is employed.After all correspondences are obtained, the projection matrix M w c can be estimated in the same way as estimating M c p.5Sphere detection and trackingThe tracking module detects and tracks the translation of the sphere relative to the camera.The translation of the sphere is defined as the position of the sphere’s center in the camera coordinate system,which can be located via its projection(conic section)in the camera.However,it is difficult to define the rotation since the sphere is centro-symmetric in shape.So we embed four IR LEDs on the surface of the sphere and employ a Wiimote to track them. Based on the tracking result from Wiimote and the cali-brated relationship between the Wiimote and the camera, we can calculate the rotation of the sphere relative to the camera.The configuration is user-friendly in appearance since the IR LEDs embedded are almost invisible.Experi-mental results also show that it achieves quite good accuracy and robustness.5.1DetectionWefirst use the Hough transform circle detection algorithm to detect a circle to approximate the conic section in the initial frame of the video stream and employ the algorithm in[20]to locate the center of the sphere.The rotation of the sphere is defined as follows:we define an object coordinate system in the center of the sphere.The x-y plane of it parallels the plane formed by the four IR LEDs.An illus-trativefigure is shown in Fig.5a.The rotation of the sphere is then defined as the rotation from the object coordinate system to the camera coordinate system.We calculate it as follows:given the detected positions of the four IR LEDs in the Wiimote,we calculate their3D coordinates in the Wiimote coordinate system using the P4P algorithm in [22].The four3D points are then projected to the camera image plane by the projection matrix M w c.Finally,we can calculate their3D coordinates in the camera coordinate system using(4)since we have located the center of the440Z.Li et al.sphere.Assuming that they are L c i;i¼1...;4;we can obtain the base vectors of the object coordinate system and the rotation matrix from the object to the camera byi¼L c3ÀL c2L c3ÀL c2;j¼L c1ÀL c4L c1ÀL c4;k¼i jR c¼½i;j;kð9ÞWe further refine the translation and rotation by mini-mizing the following squared errors:X4 i¼1R c L oiþt cÀL c i22ð10Þwhere L o i;i¼1...4are the3D coordinates of the four IR LEDs in the object coordinate system,which are manually measured.5.2TrackingAfter detecting the translation and rotation of the sphere in the initial frame,we track them in the subsequent frames.The tracking state is the concatenation of the rotation and translation vector in the following form:s¼ðr x r y r z t x t y t zÞð11Þwhere r x,r y,r z are the Euler angles and t x,t y,t z are the translations along the x,y and z axis,respectively.Particlefilter[23]is employed to estimate the posterior density of the pose.It represents the pose as a set of dis-crete particles.Each particle has a weight to indicate how confident it is to represent the pose.The two main com-ponents of a particlefilter are the state dynamic model and the observation model.The state dynamic model deter-mines how the particles propagate from frame to frame. The observation model determines how much weight is assigned to particles providing the observation at that frame.The workflow of the particlefilter used in our sys-tem is shown is Fig.6.We describe the state dynamic model and observation model as follows:5.2.1State dynamic modelSince the sphere is freely moved,a simple random walk model based on a uniform density U about the previous state is used.The variable e represents the uncertainty about the movement of the sphere.pðs k j s kÀ1Þ¼Uðs kÀ1Àe;s kÀ1þeÞð12Þ5.2.2Observation modelThe observations in our algorithm are the edge map obtained by Canny edge detector and the detected position of the four IR LEDs.To evaluate the likelihood of each particle,wefirst re-project the sphere and the four IR LEDs to the image plane according to the pose represented by the particle.The projected sphere is approximately a circle. Then we check how many edge points are on the circle.An edge point is regarded as on the circle if its distance to the circle is within5pixels.For each degree of the360°cir-cumference,we check if there is an on-edge point.If the number of the on-edge points is less than90,i.e.,one-fourth of the complete circumference,we judge that the on-edge points are not enough to match a valid circle,and a very low likelihood is assigned to this particle.Otherwise, wefit a circle centered close to the projected circle based on these on-edge points.Itsfitting rate(the ratio of the inliers to the total on-edge points)is assigned to the particle as its likelihood.To give a more precise tracking result,we introduced a replacement scheme into our observation model.For particle whosefitting rate is above a threshold (0.6in our implementation),we relocate the center of the sphere based on thefitted circle and recalculate its rotation based on the detected IR LEDs,and replace the translation and rotation of the particle with the calculated result.In this way,each particle surviving from the evaluation proce-dures will represent a good approximation of the real sphere in the scene.5.3Alternative:tracking with cardboardThe Wiimote tracking configuration works quite well in our experiments.However,it requires an extra Wiimote as the tracking device,and also a calibration step before using the Wiimote.Alternatively,we develop another configu-ration to track the rotation of the sphere which requires noAn interactive handheld spherical3D object display system441。

高三英语社会问题解决方案评估指标确定单选题50道1.Which aspect is the most important when evaluating a solution to social problems?A.EfficiencyB.CostC.SustainabilityD.Popularity答案：C。

本题考查社会问题解决方案评估指标中的重要性判断。

选项A“Efficiency（ 效率）”很重要，但不是最重要的唯一标准。

选项B“Cost（ 成本）”也只是一个方面。

选项D“Popularity（ 受欢迎程度）”并非核心重要指标。

而选项C“Sustainability 可持续性）”对于长期解决社会问题至关重要，因为只有可持续的解决方案才能真正有效地解决问题而不会带来新的问题。

2.In assessing social problem solutions, what should be given top priority?A.Quick implementationB.Long-term effectivenessC.Low initial investmentD.High media attention答案：B。

选项A“Quick implementation（快速实施）”有一定好处，但如果不能长期有效也不行。

选项C“Low initial investment 低初始投资）”不是最重要的考量。

选项D“High media attention 高媒体关注度）”不是关键因素。

选项B“Long-term effectiveness（长期有效性）”在评估社会问题解决方案时应给予最高优先级，因为只有长期有效的方案才能真正解决社会问题。

3.Which factor is crucial in determining the importance of a social problem solution?A.Number of supportersB.Speed of resultsC.Impact on future generationsD.Immediate popularity答案：C。

Submarines are fascinating vessels that have captured the imagination of many for centuries.They are capable of diving deep into the ocean,exploring the mysteries of the underwater world.In this essay,we will discuss the concept of submarine experiments, their importance,and the various types of experiments that can be conducted.IntroductionThe first recorded concept of a submarine dates back to the16th century when a Dutch inventor,Cornelius Drebbel,built a vessel that could submerge and travel underwater. Since then,the technology has advanced significantly,and submarines are now an integral part of naval forces worldwide.They are used for various purposes,including military operations,scientific research,and exploration.Importance of Submarine ExperimentsSubmarine experiments are crucial for several reasons:1.Technological Advancement:Experiments help in the development and testing of new technologies that can improve the capabilities of submarines,such as propulsion systems, navigation,and communication equipment.2.Safety:Ensuring the safety of submarine operations is paramount.Experiments can help identify potential risks and develop safety protocols to mitigate them.3.Environmental Impact:As submarines explore deeper and more remote parts of the ocean,it is essential to understand their impact on marine ecosystems.This can help in the formulation of regulations to protect the environment.4.Scientific Research:Submarines provide a unique platform for conducting research in areas such as marine biology,geology,and oceanography.Experiments can lead to new discoveries and a better understanding of the ocean.Types of Submarine Experiments1.Marine Biology Studies:Submarines can be used to study marine life in their natural habitat.This can include observing the behavior of deepsea creatures,collecting samples for genetic analysis,and studying the effects of pollution on marine ecosystems.2.Geological Exploration:The ocean floor is home to a wealth of geological features, such as underwater volcanoes,hydrothermal vents,and deepsea trenches.Submarines canbe equipped with specialized equipment to study these features and collect samples.3.Oceanographic Research:Understanding the dynamics of the ocean is essential for predicting weather patterns,understanding climate change,and managing marine resources.Submarines can be used to collect data on ocean currents,water temperature, and salinity.itary Operations:While not an experiment in the traditional sense,the use of submarines in military exercises is a form of testing their capabilities.This can include testing stealth technology,underwater navigation,and the deployment of weapons.5.Engineering Tests:Submarines are subjected to extreme pressures and conditions. Engineering tests can help in understanding the structural integrity of the vessel and the performance of its systems under these conditions.ConclusionSubmarine experiments play a vital role in advancing our knowledge of the ocean and its inhabitants.They also contribute to the development of safer,more efficient,and environmentally friendly submarine technology.As we continue to explore the depths of the ocean,the importance of these experiments will only grow.In conclusion,the world beneath the oceans surface is as vast and mysterious as the cosmos above.Submarine experiments are the key to unlocking its secrets and ensuring that we can explore and protect it responsibly.Whether for scientific discovery, technological advancement,or military strategy,the role of submarines in our future is as significant as it has ever been.。

2025年研究生考试考研英语(一201)模拟试题及答案指导一、完型填空（10分）研究生考试考研英语(一201)一、完形填空（共20题，每小题1分，满分20分）Passage:In recent years, there has been a surge in interest in mindfulness. Mindfulness, simply put, is the practice of paying attention to the present moment without judgment. It involves observing your thoughts, feelings, and sensations (1)they arise, acknowledging them without getting caught up in them.This approach to awareness has its roots in ancient Eastern traditions, such as Buddhism, where it was (2) as a path to enlightenment. However, mindfulness has gained widespread (3) in the West (4) research has shown its numerous benefits for mental and physical health.Practicing mindfulness can help reduce stress, improve focus, (5)emotional regulation, and boost overall well-being. Studies have (6) a link between mindfulness and a decreased risk of chronic diseases, such as heart disease and depression. (7), mindfulness can enhance (8)skills, such as communication and empathy.Some people (9) mindfulness through formal meditation practices, while others (10) it into their daily lives by paying attention (11) while walking, eating, or (12) to music. Regardless of the approach, the key is (13) present and (14) judgment.Mindfulness is not a quick fix. It requires (15) and (16). However, with (17) practice, it can become a powerful tool for (18) stress, enhancing well-being, and living a more (19) life.(20) all, mindfulness teaches us to be present and appreciate the beauty of the now.Answer Key:1.as2.viewed3.acceptance4.because5.enhance6.established7.Furthermore8.interpersonal9.cultivate10.incorporate11.fully12.listening13.staying14.non-judgmentally15.patiencemitment17.consistent18.managing19.fulfilling20.Above二、传统阅读理解（本部分有4大题，每大题10分，共40分）第一题文章正文：Title: The Last of the TitansIn the heart of the Indian Ocean, lies a small, obscure island known as Kikonyogo. Unlike the grandeur of Maldives or the allure of Bali, Kikonyogo is a place many would scarcely bother to find on a map. Yet, it holds within its shrunken frame a peculiar secret: it is home to the largest living tree in the world.This colossal tree, estimated to be over 70 meters in circumference and with a girth thick enough to wrap around four average-sized cars, towers above the surrounding vegetation. Its branches stretch out like ancient fingers reaching for the sky, embracing the sunlight that filters through the dense canopy. Thetree, though largely surrounded by ruins of what once was a thriving civilization, stands tall, its roots deeply entrenched in the earth and its leaves whispering tales of centuries passed.The locals, a remnant of the once vibrant community that thrived around these ancient woods, have long held traditions of respecting and protecting this solitary tree. They believe it to be sacred, a guardi an of the island’s life force, a reminder of the these lands’ untouched beauty before human intervention. Despite the passage of time and the changes that have swept over Kikonyogo, the last of the titans, as it is affectionately called, remains steadfast, a testament to resilience and endurance.1.How old is the largest living tree in Kikonyogo?The largest living tree in Kikonyogo is estimated to be over 70 meters in circumference, indicating it is significantly older than any living tree on Earth.2.What does the tree look like?The tree looks like a colossal structure, with an estimated circumference of over 70 meters and a girth thick enough to wrap around four average-sized cars. Its branches stretch out like ancient fingers, and its leaves whisper tales of centuries passed.3.What role does the tree play in the local community’s traditions?The tree plays a role of being a guardian of the island’s life force and a reminder of the untouched beauty of the land before human intervention. It is considered sacred and is respected and protected by the local community.4.What is the significance of Kikonyogo’s colossal tree?The significance of Kikonyogo’s colossal tree is that it stands as a testament to resilience and endurance, surviving years and changes that have swept over Kikonyogo.5.According to the text, how does the tree fit into the natural landscape of Kikonyogo?The tree fits into the natural landscape of Kikonyogo as a solitary tree surrounded by ruins of what once was a thriving civilization. It stands tall, embracing the sunlight, and its presence is deeply intertwined with the island’s history and the local community’s traditions.第二题阅读下列短文，从每题所给的四个选项中，选出最佳答案。

Design and Practice of Blended Teaching in SmartClassroom EnvironmentLing Feng*, Xia Wang, Fang Li, Xiqiang DuanCollege of Information Science and Technology, Taishan University, Taian, China*Correspondingauthor:****************.cn************************************************AbstractOnline and offline blended teaching is the mainstream teaching mode of current classroom teaching. The emergence and application of smart classroom has injected new vitality into blended teaching, which is more convenient for the implementation of blended learning Teaching and the collection and analysis of teaching data. Starting from the concept and model of smart classroom, this paper discusses the design and practice of online and offline blended teaching in the smart classroom environment from the perspectives of teaching mode design and teaching method innovation. The purpose is to help the teacher use smart classroom to improve classroom teaching quality more efficiently and improve students' learning autonomy and enthusiasm.Keywords: Smart Classroom; Blended Teaching; Instructional Design1INTRODUCTIONWith the vigorous development of information technology and the Internet, classroom teaching has also changed from pure offline teaching to online and offline blended teaching. Online and offline blended teaching combines the advantages of traditional offline teaching with the advantages of networked online teaching. Before class, students learn online video materials prerecorded or designated by the teacher to obtain preliminary knowledge and conduct online tests. In the class, according to the students' learning situation, the teacher and students conduct discussion learning on key or confused problems. After class, students finish the homework assigned by the teacher online. Through this teaching method, the teacher plays a leading role in guiding, enlightening and monitoring the teaching process, and fully reflect students' initiative, enthusiasm and creativity as the main body of the learning process, so as to maximize students' learning effect. Smart classroom is a new teaching environment derived from the development of educational informatization. It is a full-automatic system with rich technical equipment, data collection, learning analysis, evaluation and prediction, which provides more possibilities for the teacher' teaching and students' learning. Smart classroom has built an environmental foundation for modern online and offline hybrid learning. In this environment, how to design online and offline blended teaching mode to promote teaching, improve the actual effect of teaching and give full play to the systematicness and comprehensiveness of hybrid learning is an important issue to be discussed.2SMART CLASSROOM2.1Smart classroom conceptSmart classroom is a smart physical space and data space constructed by using the Internet, cloud computing, Internet of things, big data and intelligent technology. It is a new classroom with the functions of context perception and environmental management. It is the high-end form of multimedia and network classroom and the latest form of classroom information construction. Through the smart classroom, we can base on the needs© The Author(s) 2023B. Fox et al. (Eds.): IC-ICAIE 2022, AHCS 9, pp. 7-12, 2023. https:///10.2991/978-94-6463-040-4_3of teaching activities, realize smart teaching management, provide intelligent application services, realize the effective integration of online and offline, optimize the presentation of teaching content, facilitate the acquisition of learning resources, promote classroom interaction, give full play to the main role of students, promote students' independent and personalized learning, and achieve the optimal teaching effect [1].2.2Smart classroom modelHuang Ronghuai and others [2] believe that the "smart" of smart classroom involves the optimized presentation of teaching content, convenient access to learning resources, in-depth interaction of classroom teaching, scene perception and detection, classroom layout and electrical management. It can be summarized into five dimensions: content showing, environment manageable, resources accessible, real-time interactive and situational testing The five dimensions of situational perception, which is abbreviated as "S.M.A.R.T". These five dimensions just reflect the characteristics of smart classroom, which can be called "SMART" conceptual model.Nie Fenghua et al. [1] constructed the "iSmart" model of smart classroom from the perspective of system composition. In this model, the smart classroom is composed of six systems: infrastructure, network sensor, visual management, augmented reality, real-time recording and ubiquitous technology.Two smart classroom models are shown in Figure 1.Figure 1. Two smart classroom models3THE DIFFERENCE BETWEEN SMART CLASSROOM AND MULTIMEDIA CLASSROOM3.1Different equipment environmentMultimedia classrooms are generally composed of computers, projectors, projection screens, central control systems, audio equipment and other common multimedia equipment. In addition to the projector, screen and audio equipment, other equipment is concentrated in the cabinet next to the classroom podium. All equipment is connected together through the integrated central control. Teachers can open the cabinet through the key or campus card and use multimedia equipment by operating the keys on the central control panel. The computer and central control system of the classroom are connected with the campus network, and semi intelligent management can be realized through the multimedia intelligent management system. The multimedia classroom is equipped with blackboard or whiteboard for class. The desks and chairs adopt fixed or non-fixed forms of ordinary layout. The capacity of the classroom is generally large and can accommodate 80-300 people.Smart classroom mainly relies on emerging network information technologies such as cloud computing and Internet of things, and uses multimedia technologies such as wireless projection technology, multi-screen display technology, automatic recording and broadcasting technology, wireless sensor technology and radio frequency identification technology to realize intelligent teaching function and intelligent management function. Intelligent teaching function includes two subsystems: interactive teaching system and automatic recording and broadcasting system. The intelligent management function includes the intelligent management of personnel attendance, assets and equipment, lighting, doors and windows, air, video monitoring, etc. The main equipment includes smart classroom control terminal, digital audio processor, recording and broadcasting camera, large teaching screen, interactive intelligent tablet, teaching computer, surveillance camera, infrared transponder, positioning analyzer, etc. The smart classroom is equipped with main screen and multi-screen equipment for class. Tables and chairs are in non-fixed form, which can be combined freely, and the layout of the classroom is diversified and flexible; The classroom environment is spacious, comfortable and reasonable, but the capacity is usually small, which can generally accommodate 30-80 people.8Ling Feng et al.3.2Different teaching methodsDue to the setting of teaching environment, the teaching mode of multimedia classroom still continues to use the traditional indoctrination mode, and most of the students' learning methods are traditional and passive.Flexible table and chair layout can be designed in the smart classroom, which can support various teaching modes such as ordinary lecture mode, group discussion mode and academic research mode. The teacher and students can have group discussion, group display and resource sharing. Using wireless projection technology and multi-screen display technology, the information of learners' mobile terminals can be displayed in time to facilitate sharing and communication, so as to truly realize the Student-centered Interactive teaching mode. 4DESIGN OF BLENDED TEACHING IN SMART CLASSROOM ENVIRONMENT Taking advantage of the characteristics that the intelligent classroom environment can easily obtain teaching resources and realize full interactive teaching, the three-stage teaching mode and multi round incentive teaching method are designed.4.1Three stage teaching modeThe implementation process of the three-stage teaching mode is shown in Figure 2.Figure 2. The implementation of three-stage teaching mode1) Before class: The teacher prepares for teaching and students preview and learn basic knowledge by using the online platform. The teacher carries out teaching design and prepare teaching resources, and use task driven method to mobilize students' learning enthusiasm. The teacher design the corresponding task list according to the teaching content, and refine each knowledge point into one or more executable, easy to operate and specific tasks one by one, so that students can realize the construction of their own knowledge system in the process of completing the task. Relying on the online platform of smart classroom, the teacher release students' preview tasks according to the task list, such as videos that students need to watch, expanded materials to read, topics to discuss, completed tests, etc. According to the tasks, videos, notices and materials released by the teacher online, students independently complete the preview of basic knowledge content, sort out doubts and difficulties, and complete the preview test assigned by the teacher [3].2) In class: The teacher uses online and offline integration to organize classroom teaching. In the process of teaching in the smart classroom, the teacher can synchronize the teaching content to the display terminals in different positions such as the main screen and side screen of the smart classroom, and students can watch the learning classroom content accurately and clearly in any corner of the classroom. In order to enrich the teaching contents, the teacher can display different teaching contents on different display terminals. The teacher can control the teaching content and teaching progress at any position in the classroom through the mobile terminal, and can ask questions and test at any time through the intelligent platform [4].Firstly, the teacher uses the attendance system of smart classroom or the sign in function of smart platform to check in students, and then display the preview test results of students on multiple screens to explain the problems encountered by students. The designed pre-class test is released to test students' mastery of preview knowledge and problem explanation. For the problems that some students make mistakes, select 2-3 students to explain through the election mode of the smart platform. For the problems that most students make mistakes, students will discuss in groups and display the discussion results on different display terminals. The teacher and students complete the answers and doubts of questions through comparison and comment on the results and realize students' mutual learning and common progress at the same time.Design and Practice of Blended (9)Through the two tests, the teacher can understand the inquiry situation of students' learning and select the key and difficult points and the places where there are problems according to the teaching objectives and answers, so as to further help students master the knowledge points that they do not understand deeply and vaguely, and also help the mastered students consolidate and review the relevant contents. After explaining the key and difficult points of knowledge, the teacher will show the inquiry questions related to real life in the form of animation or video. Students are divided into groups for research and discussion, and present solutions to multiple screen terminals. Then the teacher comments on the results of the students' discussion, and the students also comment on each other to obtain the final solution, so as to exercise the students' ability to analyze and solve problems.In the process of teaching, the teacher can use the intelligent platform to conduct classroom tests at any time and view the test results in time. Through the test data analysis results, the teacher can understand students' knowledge mastery and improve teaching progress and teaching behavior at any time.3) After class: The teacher analyzes and summarizes the teaching data and adjusts the teaching strategies, and the students review and preview for the next class. The video of the complete teaching process recorded by the recording and broadcasting system in the smart classroom is automatically uploaded to the teaching on-demand platform. Students can independently review on-demand. The teacher can watch the video to find the highlights and deficiencies in teaching and see the students' reactions in class, so as to lay a foundation for adjusting teaching strategies. In addition, teachers can assign homework on the smart platform and check the completion of students.4.2Integrate multiple teaching methodsThe integration and innovation form of various teaching methods is shown in Figure 3.Figure 3. Integrate multiple teaching methodsThe teacher makes full use of the activities such as "selecting", "answering", "voting", "Questionnaire", "discussion" and "in class test" of the intelligent platform or learning link to carry out two-way interactive teaching, activate the offline classroom and realize the two-way interaction between teachers and students. Through this method, the teacher turns the dull classroom into an active classroom and use online data to clearly show the students' mastery, so as to realize the requirements of "leaving traces in the learning process" and "analyzing learning data".The teacher design the teaching process and implement multiple rounds of incentives to break through the bottleneck of students' learning. The first round of motivation is online preview, watching videos and completing tests to master basic knowledge. The second round of incentive is an offline classroom interactive activity. On the basis of online preview and test, combined with teachers' explanation and interactive discussion, students can master important and difficult knowledge, analyze practical problems and master practical application, so as to enhance their interest in learning. The third round of incentive is the online in class test, which completes the clearance test around key and difficult knowledge and practical problems according to the classroom development and online teaching resources. The fourth round of incentive is online homework, which is completed according to online resources and course playback. Through multiple rounds of incentives, students can break through the learning bottleneck. Teachers can master students' learning situation according to data analysis, understand10Ling Feng et al.the differences between students, teach students according to their aptitude, promote the comprehensive and personalized development of students, and finally achieve the teaching goal.In the teaching process, teachers should make full use of a variety of teaching methods, such as case, heuristic, discussion, experience, inquiry, project and so on. For example, taking real-life problems as the teaching introduction, teachers inspire students to carry out group discussion from the perspective of the background and causes of the problems, analyze the knowledge points and ability requirements, and then simulate the solution and implementation of the problems through the combination of experiential practical teaching. Finally, through inquiry discussion and project-based practice, students can master key knowledge and cultivate practical application ability.5CONCLUSIONUsing the rich network resources and intelligent teaching environment of smart classroom, we can build a student-centered blended teaching model. This paper explores the three-stage teaching mode and teaching methods of online and offline integration, which provides some ideas and references for classroom teaching reform in the environment of smart classroom. ACKNOWLEDGMENTThis paper is the research result of the Special Subject of Teaching Science Planning in Tai'an City "Research on the Strategy of Improving the Quality of Multimedia Teaching in Primary and Secondary Schools under the Background of" Double Reduction "(Subject No.: TJK202106ZX026).REFERENCES[1]Nie Fenghua, Zhong Xiaoliu, Song Shuqiang.Smart Classroom:Conceptual Features, System Model and Construction Case [J], Modern Educational Technology, 2013.7 (23): 5-8. [2]Huang Ronghuai, Hu Yongbin, Yang Junfeng. XiaoGuangde, Concept and Characteristics of Smart Classroom [J], Research on Open Education, 2012,(2): 22-27.[3]Zhang Han, He Yazhu. Research on ClassroomTeaching Design in Smart Classroom Environment [J], Education Guide (First Half of the Month), 2021(9): 70-76.[4]Zhu Zhenshen, Zhang Junying, Gao Yin.Exploration and Practice of Classroom Teaching Mode in Colleges and Universities under the Environment of Smart Classroom [J], Informationand Computer (Theoretical Edition). 2021,33 (18): 244-246.[5]Miao Li. Research on Blended Learning in SmartClassroom Environment [J], Modern vocational education. 2021, (10):228-229.Design and Practice of Blended (11)Open Access This chapter is licensed under the ter ms of the Cr eative Commons Attr ibution-NonCommer cial 4.0 Inter national License (http://cr eativecommons.or g/licenses/by-nc/4.0/), which permits any noncommer cial use, sharing, adaptation, distr ibution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.The images or other third party material in this chapter are included in the chapter s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the chapter s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder.’’12Ling Feng et al.。

第二单元测评第一部分听力(共两节,满分30分)第一节(共5小题;每小题1.5分,满分7.5分)听下面5段对话。

每段对话后有一个小题,从题中所给的A、B、C三个选项中选出最佳选项。

听完每段对话后,你都有10秒钟的时间来回答有关小题和阅读下一小题。

每段对话仅读一遍。

1.What does the woman ask the man to do?A.Have lunch first.B.Eat slowly.C.Join in a game.2.Who are the speakers talking about?A.Their history teacher.B.Their politics teacher.C.Their Chinese teacher.3.What surprises the man?A.Jane dropped school.B.Jane made much money.C.Jane is still working.4.How does the man feel about his midterm exam?A.Satisfied.B.Surprised.C.Unsure.5.What does the man mean?A.A cold drink can be relaxing.B.Scott and Tina like to play jokes on each other.C.Humor can be helpful in embarrassing situations.第二节(共15小题;每小题1.5分,满分22.5分)听下面5段对话或独白。

每段对话或独白后有几个小题,从题中所给的A、B、C三个选项中选出最佳选项。

听每段对话或独白前,你将有时间阅读各个小题,每小题5秒钟;听完后,各小题将给出5秒钟的作答时间。

每段对话或独白读两遍。

听第6段材料,回答第6、7题。

6.Where will the package go to?A.The UK.B.The US.C.Meuch more will the man pay for the package than normal?A.10 cents.B.50 cents.C.90 cents.听第7段材料,回答第8、9题。

In the realm of technological advancements, smart glasses have emerged as a groundbreaking innovation that is reshaping the way we interact with digital information and perceive the world around us. These futuristic devices, blending seamlessly into our daily lives, offer an array of functionalities that extend far beyond conventional eyewear. This essay presents a comprehensive analysis of high-tech smart glasses, delving into their multifaceted features, applications across various domains, societal implications, and potential future developments.**I. Technological Features and Functionalities**High-tech smart glasses are a testament to the fusion of cutting-edge technologies such as augmented reality (AR), virtual reality (VR), artificial intelligence (AI), and advanced optics. Their core features can be categorized into several key aspects:1. **Display and Optical Systems**: Smart glasses utilize transparent or semi-transparent displays that overlay digital content onto the wearer's field of view, without obstructing their perception of the real world. Advanced waveguide technology or micro-projectors ensure crisp, high-resolution images, while adjustable focus mechanisms cater to individual visual needs. Some models even incorporate adaptive tinting or light-filtering capabilities for enhanced comfort and protection.2. **Sensors and Connectivity**: Equipped with an array of sensors like accelerometers, gyroscopes, proximity sensors, and cameras, smart glasses capture real-time data about the user's environment and movements. They also support wireless connectivity options such as Wi-Fi, Bluetooth, and GPS, enabling seamless integration with other devices and the internet.3. **Interaction and Control**: Users can interact with smart glasses through voice commands, hand gestures, eye tracking, or even brain-computer interfaces in some prototypes. AI-powered assistants facilitate intuitive navigation, content retrieval, and contextual assistance, enhancing the overall user experience.4. **Processing Power and Battery Life**: Embedded with powerful processors and optimized software, smart glasses can handle complex AR/VR applications and AI algorithms. Advances in battery technology and energy-efficient computing have led to longer battery life, ensuring uninterrupted usage for extended periods.**II. Applications Across Domains**The versatility of high-tech smart glasses has unlocked a myriad of applications across various sectors:1. **Enterprise and Industry**: In industries like manufacturing, logistics, and maintenance, smart glasses serve as hands-free, heads-up displays that provide workers with real-time instructions, safety alerts, and remote expert assistance, thereby enhancing productivity, accuracy, and safety. They also enable immersive training simulations and facilitate remote collaboration in the era of distributed workforces.2. **Healthcare**: Smart glasses have found applications in telemedicine, allowing doctors to conduct remote consultations and receive live guidance from specialists during procedures. They also aid in surgical planning, patient monitoring, and medical education. For individuals with visual impairments, smart glasses can enhance vision by augmenting visual cues or converting text to speech.3. **Consumer Lifestyle and Entertainment**: Consumers can use smart glasses for navigation, messaging, gaming, and immersive media consumption. They also facilitate language translation, real-time information retrieval, and social media interactions, turning everyday experiences into interactive, data-rich adventures.4. **Education**: Smart glasses can transform learning by providing immersive educational content, interactive simulations, and personalized tutoring. They facilitate experiential learning, enhancing understanding and retention of complex concepts.**III. Societal Implications**The proliferation of high-tech smart glasses raises several significant societal considerations:1. **Privacy and Security**: The ubiquitous presence of cameras and sensors in smart glasses raises concerns about privacy infringement and surveillance. Ensuring robust data encryption, strict privacy policies, and user control over data sharing is crucial to mitigate these risks.2. **Digital Divide**: The high cost and technological sophistication of smart glasses may exacerbate existing inequalities, creating a digital divide between those who can afford and access these devices and those who cannot. Efforts must be made to ensure equitable distribution and accessibility, including affordable alternatives and public initiatives.3. **Social Norms and Etiquette**: As smart glasses become more prevalent, society will need to establish new norms and etiquette around their use, particularly regarding issues like recording consent, attention management, and the blurring of physical and digital spaces.**IV. Future Developments and Opportunities**Looking ahead, several trends and advancements promise to further propel the evolution of high-tech smart glasses:1. **Advancements in Display Technology**: The development of holographic, retinal projection, or light-field displays could significantly enhance image quality, immersion, and visual comfort in smart glasses.2. **Integration with Neural Interfaces**: Combining smart glasses with non-invasive neural interfaces could enable direct mind-control, revolutionizing the way we interact with digital content and potentially unlocking new applications in fields like mental health and neurorehabilitation.3. **Extended Reality (XR) Ecosystem**: The convergence of AR, VR, and mixed reality technologies will likely lead to more integrated and seamless XR experiences, with smart glasses serving as a central hub for accessing and interacting with virtual environments and digital overlays.4. **Environmental Sustainability**: Advancements in sustainable materials,energy harvesting technologies, and circular design principles could make smart glasses more environmentally friendly, aligning with growing global concerns about e-waste and carbon footprint.In conclusion, high-tech smart glasses represent a paradigm shift in human-computer interaction, offering unparalleled convenience, functionality, and immersion. While they present numerous opportunities for transformative applications across diverse sectors, it is crucial to address associated challenges such as privacy, accessibility, and social norms. As technology continues to evolve, smart glasses are poised to play an increasingly integral role in shaping our digital futures.。