Virtual Augmented Reality Research Articles

Wifi 7: Advancements, Applications and Future Prospects

The goal of Wi-Fi 7, a major advancement in wireless networking technology, is to satisfy the increasing demand for faster data speeds, reduced latency, and more spectrum economy. Building on the success of Wi-Fi 6 and 6E. this next generation offers previously unheard-of speeds of up to 30 Gbps and improved network stability with innovations like 320 MHz channel width, 4096-QAM (Quadrature Amplitude Modulation), and Multi-Link Operation (MLO). Virtual/augmented reality (VR/AR). high-definition media streaming, sophisticated loT ecosystems, and industrial automation arc just a few of the many uses that Wi-Fi 7 is anticipated to enable. Wi-Fi 7 is expected to serve new use cases that require dependable, fast wireless connections, such smart cities, real-time telemedicine, and driverless cars, thanks to its extremely low latency and smooth multi-connection management

Diagnostic Performance of a Next-Generation Virtual/Augmented Reality Headset: A Pilot Study of Diverticulitis on CT.

Next-generation virtual/augmented reality (VR/AR) headsets may rival the desktop computer systems that are approved for clinical interpretation of radiologic images, but require validation for high-resolution low-luminance diagnoses like diverticulitis. The primary aim of this study is to compare diagnostic performance for detecting diverticulitis on CT between radiologists using a headset versus a desktop. The secondary aim is to survey participating radiologists about the usage of both devices. This pilot study retrospectively included 110 patients (mean age 64 ± 14 years, 62 women) who had abdomen/pelvis CT scans for which the report mentioned the presence or absence of diverticulitis. Scans were dichotomized and matched by time, for a total of 55 cases with diverticulitis and 55 controls with no diverticulitis. Six radiologists were oriented to the VR/AR headset (Apple Vision Pro) and viewer app (Visage Ease VP) using ten scans. They each scored 100 unknown scans on a 6-level scale for diverticulitis (1 = no diverticulitis, 6 = diverticulitis) on the headset and then on a desktop. Timepercase was recorded. Finally, they completed a survey using 5-level scales about the ease of use of the headset and viewer app (1 = difficult, 5 = easy), about their experience with the headset (1 = bad, 5 = good), and about their preference between devices (1 = desktop, 5 = headset). Summary statistics and multi-reader multi-case ROC curves were calculated. The AUC (and 95% confidence interval) for diverticulitis was 0.93 (0.88-0.97) with the headset and 0.94 (0.91-0.98) with the desktop (p = 0.40). The median (and first-third quartiles) of timepercase was 57 (41-76) seconds for the headset and 31 (22-64) seconds for the desktop (p < 0.001). Average survey scores ranged from 3.3 to 5 for ease of use, from 3 to 4.7 for experience, and from 2.2 to 3.3 for preference. Diagnostic performance for detecting diverticulitis on CT was similar between the next-generation VR/AR headset and desktop. Ease of use, experience, and preference varied across different aspects of the devices and among radiologists.

Measuring and Predicting Multisensory Reaction Latency: A Probabilistic Model for Visual-Auditory Integration.

Virtual/augmented reality (VR/AR) devices offer both immersive imagery and sound. With those wide-field cues, we can simultaneously acquire and process visual and auditory signals to quickly identify objects, make decisions, and take action. While vision often takes precedence in perception, our visual sensitivity degrades in the periphery. In contrast, auditory sensitivity can exhibit an opposite trend due to the elevated interaural time difference. What occurs when these senses are simultaneously integrated, as is common in VR applications such as 360° video watching and immersive gaming? We present a computational and probabilistic model to predict VR users' reaction latency to visual-auditory multisensory targets. To this aim, we first conducted a psychophysical experiment in VR to measure the reaction latency by tracking the onset of eye movements. Experiments with numerical metrics and user studies with naturalistic scenarios showcase the model's accuracy and generalizability. Lastly, we discuss the potential applications, such as measuring the sufficiency of target appearance duration in immersive video playback, and suggesting the optimal spatial layouts for AR interface design.

Fabrication of slanted gratings with high refractive index starting from master nanoimprint mold

Recently, nanoimprinting has attracted a new round of attention in the industry due to the boom in demand for augmented reality/virtual reality (AR/VR), metalens and microlens, and even semiconductors. Slanted gratings have great application prospects in AR/VR displays because of their high efficiency in light coupling. UV-Nanoimprint lithography (UV-NIL) has been identified as one of the most feasible routes for mass manufacture of high refractive index (RI) slanted gratings. This paper presents a fabrication of high RI slanted gratings based on UV-NIL. A comprehensive study on the optical principles of slanted gratings is conducted, followed by simulation-based optimization of the grating parameters. The key element for applying nanoimprint to fabricate slanted gratings is the master mold, which is acquired by a tilted angle etching of metal gratings as an etching mask on silicon wafers with F-based plasma. The influence of experimental parameters, such as the etching power and etching mask thickness on the morphology of the slanted gratings on the master mold are investigated. The working mold was simply duplicated from the master mold by UV-NIL with a low surface energy working mold material. The high RI slanted gratings were achieved by imprinting a UV-curable resin with high RI. Finally, experimental verification was performed to assess the optical performance of the slanted gratings.

Evaluating Layout Dimensionalities in PC+VR Asymmetric Collaborative Decision Making

With the commercialization of virtual/augmented reality (VR/AR) devices, there is an increasing interest in combining immersive and non-immersive devices (e.g., desktop computers) for asymmetric collaborations. While such asymmetric settings have been examined in social platforms, significant questions around layout dimensionality in data-driven decision-making remain underexplored. A crucial inquiry arises: although presenting a consistent 3D virtual world on both immersive and non-immersive platforms has been a common practice in social applications, does the same guideline apply to lay out data? Or should data placement be optimized locally according to each device's display capacity? This study aims to provide empirical insights into the user experience of asymmetric collaboration in data-driven decision-making. We tested practical dimensionality combinations between PC and VR, resulting in three conditions: PC2D+VR2D, PC2D+VR3D, and PC3D+VR3D. The results revealed a preference for PC2D+VR3D, and PC2D+VR2D led to the quickest task completion. Our investigation facilitates an in-depth discussion of the trade-offs associated with different layout dimensionalities in asymmetric collaborations.

Совершенствование преподавания инженерно-графических дисциплин

The article is devoted to the study of modern methods of teaching engineering and graphic disciplines with an emphasis on the use of digital technologies such as computer-aided design (CAD) and virtual/augmented reality (VR/AR). In the context of rapidly developing engineering practice, traditional teaching methods, including manual drawing and standard teaching approaches, are becoming less relevant. As part of the research conducted in the 2023-2024 academic year, an experiment was organized in which two groups of students took part: one studied using traditional methods, the other used modern CAD and VR/AR technologies. The experiment showed that the use of these technologies significantly increases the level of material assimilation and motivation of students. CAD systems allow students to accelerate the process of mastering design skills and create more accurate drawings, and virtual reality technologies help to better visualize complex spatial structures, which contributes to a deep understanding of the educational material. The article offers recommendations on the integration of these technologies into the educational process aimed at improving the effectiveness of teaching engineering and graphic disciplines and improving the preparation of students for future professional activities in a rapidly changing technological environment.

Innovative Approaches of E-Learning in College Education: Global Experience

Thanks to the rapid development of digital and information and communication technologies, colleges around the world are actively using new models of e-learning. The purpose of this study was to analyze modern e-learning tools used in colleges in different countries. The PRISMA approach was used for this study. Based on the previously formed 7 criteria related to the content, methodology, and scientific novelty of the study, 50 items of current literature were selected for analysis. The date range was from 2012 to 2023. The results demonstrate the importance of using electronic technologies in modern colleges. They develop the formation of not only theoretical but also practical skills. For example, the use of tools such as virtual augmented reality, or simulation technologies contribute to the development of practical skills in students. The proposed results have shown that micro-education, social education and gamification of education are integral elements of modern educational practice based on innovations. The conclusions summarize that the most common electronic technologies are remote platforms, mobile applications, and interactive technologies. For practical specialties less popular, but important are simulation technologies and virtual reality. In addition, the college's e-learning platform makes use of augmented reality, blockchain technology and analytical tools. All of these technologies support the growth of e-learning at the college level.

Method for the determination of the luminance of two-photon vision stimuli.

Two-photon vision is a new and developing field in vision science. The phenomenon is based on visual perception of pulsed infrared lasers (800-1300 nm) due to the isomerization of visual pigments caused by two-photon absorption, with color perception corresponding to a wavelength about one-half of the stimulating wavelength in the near-infrared spectral range. Future applications of this effect, both in medical diagnostics and in virtual/augmented reality (VR/AR), require the ability to determine the luminance of the two-photon stimuli. However, the luminous efficiency function V(λ) outside of the visible range is unknown, requiring a non-standard approach to quantifying the luminance of two-photon stimuli. This study proposes a brightness adjustment method to determine the subjective luminance of two-photon infrared stimuli using photometric units. The repeatability of the proposed method with the background on was approximately equal to 407 td, more than twice as good as with the background off. In this report, we present the relationship between the luminance of two-photon stimuli and a physical quantity proposed for the first time: two-photon retinal illuminance. This relationship enables the prediction of stimulus luminance that could achieve nearly 670 cd/m2 within the safe range of laser power for the eye.

Real-Time Indoor Visible Light Positioning (VLP) Using Long Short Term Memory Neural Network (LSTM-NN) with Principal Component Analysis (PCA).

New applications such as augmented reality/virtual reality (AR/VR), Internet-of-Things (IOT), autonomous mobile robot (AMR) services, etc., require high reliability and high accuracy real-time positioning and tracking of persons and devices in indoor areas. Among the different visible-light-positioning (VLP) schemes, such as proximity, time-of-arrival (TOA), time-difference-of-arrival (TDOA), angle-of-arrival (AOA), and received-signal-strength (RSS), the RSS scheme is relatively easy to implement. Among these VLP methods, the RSS method is simple and efficient. As the received optical power has an inverse relationship with the distance between the LED transmitter (Tx) and the photodiode (PD) receiver (Rx), position information can be estimated by studying the received optical power from different Txs. In this work, we propose and experimentally demonstrate a real-time VLP system utilizing long short-term memory neural network (LSTM-NN) with principal component analysis (PCA) to mitigate high positioning error, particularly at the positioning unit cell boundaries. Experimental results show that in a positioning unit cell of 100 × 100 × 250 cm3, the average positioning error is 5.912 cm when using LSTM-NN only. By utilizing the PCA, we can observe that the positioning accuracy can be significantly enhanced to 1.806 cm, particularly at the unit cell boundaries and cell corners, showing a positioning error reduction of 69.45%. In the cumulative distribution function (CDF) measurements, when using only the LSTM-NN model, the positioning error of 95% of the experimental data is >15 cm; while using the LSTM-NN with PCA model, the error is reduced to <5 cm. In addition, we also experimentally demonstrate that the proposed real-time VLP system can also be used to predict the direction and the trajectory of the moving Rx.

Auxetic kirigami structure-based self-powered strain sensor with customizable performance using machine learning

Recently, soft material based wearable sensors have discovered numerous applications in healthcare, sports monitoring, and virtual reality/augmented reality (VR/AR) systems. For these sensors, fulfilling user-specified requirements rather than just improving the sensor performance has become an important issue. In this study, a self-powered piezo-transmittance type strain sensor based on auxetic structures was optimized for configurable and user-specified characteristics using a machine-learning surrogate model. The sensor mechanism is based on the optical transmittance change induced by the gap opening of the auxetic kirigami structure. The sensor performance was analyzed according to the geometric design variables, and the optimal design was determined using Bayesian and Gaussian process to maximize the sensor performance for different purposes. The optimally designed geometries were used for self-powered sensors on a structural health monitoring (SHM) system, a human motion monitoring (HMM) system for monitoring sports performance and incorporated into an AR system.

Reduction of surgical complications via 3D models during robotic assisted radical prostatectomy: review of current evidence and meta-analysis

The use of 3-dimensional (3D) technology has become increasingly popular across different surgical specialities to improve surgical outcomes. 3D technology has the potential to be applied to robotic assisted radical prostatectomy to visualise the patient’s prostate anatomy to be used as a preoperative and peri operative surgical guide. This literature review aims to analyse all relevant pre-existing research on this topic. Following PRISMA guidelines, a search was carried out on PubMed, Medline, and Scopus. A total of seven studies were included in this literature review; two of which used printed-3D models and the remaining five using virtual augmented reality (AR) 3D models. Results displayed variation with select studies presenting that the use of 3D models enhances surgical outcomes and reduces complications whilst others displayed conflicting evidence. The use of 3D modelling within surgery has potential to improve various areas. This includes the potential surgical outcomes, including complication rates, due to improved planning and education.

Evaluating the effect of using augmented reality (Metaverse) on improving the teaching and academic performance

This study aimed at evaluating the effect of employing the augmented reality (metaverse) on improving the process of teaching and academic performance. An electronic questionnaire containing five questions was distributed to the academic groups that received the lesson using augmented virtual reality (Metaverse). The aim of the questions was to evaluate their experience, and after they answered the questions, the answers were analyzed in the form of percentages and frequencies. The study sample consisted of (97) students from Al-Ain University enrolled in the programs of (special education, nutrition, and applied sociology), to whom the experiment was applied using augmented virtual reality in teaching during their academic course. The results revealed that (83%) of the respondents reported that the augmented virtual reality contributed to understanding the concepts of the lesson well, (79%) felt enjoyment in using this technique, (75%) suggested that the technique enhanced their involvement in the content well, (68%) suggested that augmented virtual reality could be a useful educational instrument in the future, and (77%) confirmed that the lesson's objectives were achieved by using metaverse technique in teaching. However, several challenges were faced by students, including the used language (only English) and the negative effects of bad quality of used glasses. Based on the findings, the study recommended addressing several key areas for optimizing the use of augmented virtual reality (AVR) in teaching. For example, diversifying language options for AVR content is crucial to accommodating the linguistic diversity among students, thereby enhancing accessibility and comprehension. Additionally, we should invest in high-quality equipment and implement regular maintenance protocols to enhance the quality of equipment, specifically addressing issues related to the negative effects of subpar AVR hardware.

Patents in metaverse: an analysis of scope and challenges

ABSTRACT ‘Metaverse’ is set to be the disruptive technology which is about to bring an overhaul in the functioning of myriad sectors ranging from education, entertainment, health care, businesses amongst others. The key feature of this technology is the immersion of physical world into a virtual world. Metaverse in a way finds its roots on the technologies of Virtual/ Augmented Reality (VR/AR) which essentially are about simulating real world and augmenting the real – world experience in the digital world. Intellectual Property Rights which exist for protection of intangible assets, hence are vital in perspective of Metaverse. This research analyses the IP form of Patents in reference to Metaverse. Patents are an attractive choice due to the commercial advantage and the higher level of protection it offers compared to other IP forms. The trend of surge in patent applications seen with emerging technologies like AI and Blockchain is likely to be reflected with metaverse. The article views the metaverse and patent domain through an overarching lens gauging the possible scope and challenges. The analysis is based on US, EU and Indian patent laws to get a comprehensive picture across the world.

Research on Virtual Simulation Experiment Teaching of Scraper Conveyor Condition Monitoring and Fault Diagnosis

The scraper conveyor status monitoring and fault diagnosis virtual simulation experiment system is designed and developed based on the operating environment of the scraper conveyor in the fully mechanized mining face. Using augmented virtual reality teaching resources, through immersive display and interactive operation experiments, students are guided on basis of scraper conveyor mechanical cognition, master the virtual teaching experiment of state monitoring and fault diagnosis such as broken chain monitoring, motor fault classification and identification, reducer compound fault separation, etc. The teaching practice shows that the system can overcome the harsh production environment in coal mines and the risk factors caused by equipment failure, improve students' understanding of the mechanical fault diagnosis technology, and mobilize students' enthusiasm for experiments and initiative to enhance students' innovative ability.

Comparison of reality and illusion of wetness on soft materials and the multisensory perceptual space of wetness illusion

Skin contact with cold objects can induce the perception of wetness, known as the wetness illusion, even in the absence of actual moisture. However, the differences between wetness perceived from moisture and cooled-dry soft materials and how the material parameters affect the wetness illusion from cooled-dry soft materials remain unclear. This study recruited 12 women and 12 men to touch paired moisture and dry fabrics to compare the prescription and intensity of wetness, suggesting that the wetness illusion focused more on roughness and stickiness while the wetness of moisture fabrics sensed more on coldness. Another 12 women touched cooled-dry materials with different temperatures (10°C and 15°C), thicknesses (0.75/0.73 and 1.99/1.96 mm), and dynamic friction coefficients (mean coefficient of friction) (0.17 and 1.88), rating on wetness dissimilarity and intensity of wetness, coldness, softness, and roughness. Data were illustrated in a two-dimensional space by multidimensional scaling, in which dimension 1 represented the haptic perception in wetness, most related to the mean coefficient of friction, and dimension 2 represented the coldness perception in wetness, most related to temperature. Overall, the mean coefficient of friction and the temperature of the material had a strong influence on the wetness illusion, while the thickness had less impact. This study improves the understanding of wetness illusion and sheds light on the reproduction of wetness perception in multisensory augmented virtual reality, such as immersive gaming and virtual dress fitting.

Comparing the effects of augmented virtual reality treadmill training versus conventional treadmill training in patients with stage II-III Parkinson's disease: the VIRTREAD-PD randomized controlled trial protocol.

Intensive treadmill training (TT) has been documented to improve gait parameters and functional independence in Parkinson's Disease (PD), but the optimal intervention protocol and the criteria for tailoring the intervention to patients' performances are lacking. TT may be integrated with augmented virtual reality (AVR), however, evidence of the effectiveness of this combined treatment is still limited. Moreover, prognostic biomarkers of rehabilitation, potentially useful to customize the treatment, are currently missing. The primary aim of this study is to compare the effects on gait performances of TT + AVR versus TT alone in II-III stage PD patients with gait disturbance. Secondary aims are to assess the effects on balance, gait parameters and other motor and non-motor symptoms, and patient's satisfaction and adherence to the treatment. As an exploratory aim, the study attempts to identify biomarkers of neuroplasticity detecting changes in Neurofilament Light Chain concentration T0-T1 and to identify prognostic biomarkers associated to blood-derived Extracellular Vesicles. Single-center, randomized controlled single-blind trial comparing TT + AVR vs. TT in II-III stage PD patients with gait disturbances. Assessment will be performed at baseline (T0), end of training (T1), 3 (T2) and 6 months (T3, phone interview) from T1. The primary outcome is difference in gait performance assessed with the Tinetti Performance-Oriented Mobility Assessment gait scale at T1. Secondary outcomes are differences in gait performance at T2, in balance and spatial-temporal gait parameters at T1 and T2, patients' satisfaction and adherence. Changes in falls, functional mobility, functional autonomy, cognition, mood, and quality of life will be also assessed at different timepoints. The G*Power software was used to estimate a sample size of 20 subjects per group (power 0.95, α < 0.05), raised to 24 per group to compensate for potential drop-outs. Both interventions will be customized and progressive, based on the participant's performance, according to a predefined protocol. This study will provide data on the possible superiority of AVR-associated TT over conventional TT in improving gait and other motor and non-motor symptoms in persons with PD and gait disturbances. Results of the exploratory analysis could add information in the field of biomarker research in PD rehabilitation.

Bottom angle control mechanism and optimization of slanted gratings for optical applications

Slanted gratings serve as a crucial component in the optical waveguide couplers utilized in augmented virtual reality (AVR) devices. The flat bottom surface of slanted gratings ensures excellent diffraction efficiency of the couplers. However, achieving a flat bottom surface during the fabrication process poses challenges. This study presents a comprehensive investigation on the process control of the bottom angle using both simulation predictions based on available process parameters and experimental methods. The results obtained from the experimental procedures clearly demonstrate that the bottom angle is significantly influenced by the angular dependence of etching yield. Various ion incident energies and Ar/CHF3 gas components were employed to modulate the angular dependence of etching yield, thereby controlling the bottom angle in the reactive ion beam etching system. The effects of the ion incident energies and the flow ratios of the Ar/CHF3 gases on the bottom angle were thoroughly investigated. The findings of this study provide valuable insights for manufacturing slanted gratings and contribute to the advancement of AVR technology.

Early introduction of simulation in the medical curriculum: the MedInTo perspective.

Despite the increasing body of evidence supporting the use of simulation in medicine, a question remains: when should we introduce it into the medical school's curriculum? We present the experience and future perspectives of the MD program in Medicine and Surgery of University of Turin-MedInTo. Since its launch, MedInTo has been dedicated to integrating innovative teaching approaches at the early stages into the medical curriculum. Herewith, we describe a case-based approach for our activities, which includes the utilization of simulation for emergency medical care training for students and the integration of virtual and augmented reality technology. Dedicated surgical training activities using virtual-augmented reality and life-like simulator for students are also described.

Researching Influences of Learner Experience on AR/VR Adoption - The Case of Vietnamese Universities

Aim/Purpose: The study aims to analyze the elements/factors that impact students’ augmented reality/virtual reality (AR/VR) adoption through their behavior in Vietnamese higher education. In particular, the research demonstrates the influences of and relationships between multiple goals, learner experience, and barriers to adopting AR/VR. Background: The widespread adoption of digital transformation in numerous industries demonstrates its prospects and potential for growth. Many cutting-edge technologies, including AR and VR, have been included in educational activities because they have the potential to elevate academic standards across numerous colleges. However, their implementation and practice within higher education appear confusing to lecturers, organizations, and, in particular, students. Their innovative nature and differences are the fundamental causes. Hence, thoroughly elaborating the elements that impact the adoption of students – the target audience – through investigating the behavior if these factors are crucial to ensure the benefits of AR/VR are leveraged while the implementation procedures are enhanced. Methodology: By integrating earlier research, the research proposes a theoretical framework to explore how learners of AR/VR adopt these technologies. Discussion group interviews with professionals, namely four lecturers at Vietnam universities, were conducted. The professionals adjusted elements and changed the scales in order to optimize them in accordance with the context of Vietnamese universities. Additionally, the authors surveyed 200 students whose responses were transformed into numerical data. SmartPLS-SEM 4.0.9.3 software was used to test whether specific hypotheses were accepted or rejected. Contribution: The research holds immense significance as it employs customer behavior as the foundational theory to construct a proposed model delineating the influence of learner experience on multiple goals and AR/VR adoption. Moreover, the study’s findings empower educational establishments to strategically allocate resources toward enhancing student experiences, aligning with learner goals, and consequently augmenting the adoption of AR/VR technologies. Findings: Regarding the relationship between learner experience and multiple goals, the findings indicate that convenience experience greatly impacts academic goals and social goals. Immersive experience also has a remarkable influence on academic goals, social goals, and practical goals. As regards the impact of multiple goals on AR/VR adoption, the research reveals that academic, social, and practical goals have a significant effect on such adoption. Concerning the correlation between learner experience and AR/VR adoption, it can be seen that usage experience and entertainment experience have a beneficial effect on such adoption. Recommendations for Practitioners: In terms of practical contributions, educational organizations in Vietnam can use the research during AR/VR implementation processes to maximize the benefits of AR/VR in education. Recommendation for Researchers: The authors conduct a theoretical research framework for the adoption of AR/VR technology into Vietnam’s higher education digital platform. The research approaches a different aspect in the context of higher education, which considers students as customers based on prior research on customer behaviors through multiple goals and learner experiences to evaluate their impacts on the AR/VR adoption of students. Impact on Society: AR/VR has achieved extensive utilization and widespread acclaim across various sectors, notably education. Within the context of higher education institutions, the integration of AR/VR applications not only has advantages but also presents associated challenges. Therefore, the present inquiry was undertaken to elucidate the determinants influencing students’ receptiveness toward AR/VR utilization. Educational establishments can leverage the insights gained from analyzing the learner experience and multifaceted objectives of, as well as impediments to, AR/VR assimilation to enhance favorable elements and mitigate unfavorable aspects during the process of AR/VR implementation. The overarching objective is to elevate the degree of AR/VR adoption among students. Future Research: Further research can consult the customer behavior approach regarding technological adoption in educational contexts. In addition, apart from adoption, dependent variables can be studied, such as satisfaction with or decision to use AR/VR in future research.

Current Applications of VR/AR (Virtual Reality/Augmented Reality) in Pediatric Neurosurgery.

Neurosurgical procedures are some of the most complex procedures in medicine and since the advent of the field, planning, performing, and learning them has challenged the neurosurgeon. Virtual reality (VR) and augmented reality (AR) are making these challenges more manageable. VR refers to a virtual digital environment that can be experienced usually through use of stereoscopic glasses and controllers. AR, on the other hand, fuses the natural environment with virtual images, such as superimposing a preoperative MRI image on to the surgical field [1]. They initially were used primarily as neuronavigational tools but soon their potential in other areas of surgery, such as planning, education, and assessment, was noted and explored. Through this chapter, we outline the history and evolution of these two technologies over the past few decades, describe the current state of the technology and its uses, and postulate future directions for research and implementation.