·高被引論文摘要·

被引頻次：473

國內(nèi)外虛擬現(xiàn)實技術的研究現(xiàn)狀

姜學智，李忠華

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·高被引論文摘要·

被引頻次：473

國內(nèi)外虛擬現(xiàn)實技術的研究現(xiàn)狀

姜學智，李忠華

摘要：虛擬現(xiàn)實技術是由計算機產(chǎn)生，通過視、聽、觸覺等作用，使用戶產(chǎn)生身臨其境感覺的交互式視景仿真，具有多感知性、存在感、交互性和自主性等特征，文章介紹了動態(tài)環(huán)境建模技術，實時三維圖形生成技術，立體顯示和傳感器技術，應用系統(tǒng)開發(fā)工具，系統(tǒng)集成技術。目前已在軍事、醫(yī)學、設計和娛樂等領域得到了廣泛應用。美日等發(fā)達國家對其進行了廣泛的研究，取得了重大成果。國內(nèi)的研究也取得了一定的成果。 虛擬現(xiàn)實技術是現(xiàn)代仿真技術的一個重要發(fā)展方向，是一種多源信息熔合的交互式的三維動態(tài)視景和實體行為的系統(tǒng)仿真。文章從中國古代的模擬飛行動物的有聲風箏到現(xiàn)代美國飛行模擬器的發(fā)明；從虛擬現(xiàn)實的“Artificial Reality”到“Virtual Reality”、三個關鍵元素到三個基本特征的提出，文章首次從新的視角闡述虛擬現(xiàn)實技術的演變發(fā)展史及其理論形成，概括了VR發(fā)展的特點。首次提出用通式來表達VR的屬性。進一步地簡單介紹了VR技術在軍事、工程、醫(yī)學、文化教育等方面取得的成果和應用。最后展望了虛擬現(xiàn)實技術的發(fā)展前景，未來研究的熱點。 虛擬現(xiàn)實是人類在探索自然過程中創(chuàng)造形成的一種用于認識自然、模擬自然，進而更好地適應和利用自然的科學方法和技術。文中在分析虛擬現(xiàn)實全過程的基礎上，給出虛擬現(xiàn)實問題的不同分類及一種理論表達，并抽象出虛擬現(xiàn)實領域的三大科學技術問題類；在此基礎上從虛擬現(xiàn)實中的建模方法、虛擬現(xiàn)實表現(xiàn)技術、人機交互及設備、虛擬現(xiàn)實開發(fā)平臺與支撐環(huán)境和虛擬現(xiàn)實應用等幾個方面論述了虛擬現(xiàn)實當前的主要研究目標、研究成果和發(fā)展趨勢；最后指出虛擬現(xiàn)實需要進一步致力研究解決的若干理論和技術問題。 虛擬現(xiàn)實技術是多功能的交互技術，該文介紹了虛擬現(xiàn)實技術及其發(fā)展過程、概念特征、研究內(nèi)容以及應用的主要領域，并且結合虛擬現(xiàn)實技術的應用展望了虛擬現(xiàn)實技術的發(fā)展前景。 虛擬現(xiàn)實技術的特征可用3個I，即Immersion（沉浸感，也稱浸入感、臨場感）、Interaction（交互性）、Imagination（想象力）來描述。其中，沉浸感能使用戶感受到真切地進入到虛擬空間之中，用戶將感覺不到身體所處的外部環(huán)境，而“融合”到虛擬世界中去；交互性則能使用戶實時地控制虛擬空間中虛擬物體的行為，從而使用戶感覺到自己是虛擬空間的主體，用戶還可通過三維交互設備直接控制虛擬世界中的對象；而想象力則是人對虛擬空間的創(chuàng)造能力。 建模技術是虛擬現(xiàn)實中的關鍵技術之一，經(jīng)歷了從幾何建模、物理建模到行為建模的發(fā)展進程，行為建模方法真正體現(xiàn)了虛擬現(xiàn)實的特征。目前，以行為建模方法為代表的新一代建模方法的研究方興未艾，其應用前景非?？捎^。 分析了虛擬現(xiàn)實（VR）技術區(qū)別于相鄰近的技術的重要特征，回顧了虛擬現(xiàn)實技術發(fā)展的三個階段。介紹了虛擬現(xiàn)實技術在美國等國家的研究現(xiàn)狀、主要技術及關鍵技術的開發(fā)狀況。 虛擬現(xiàn)實是一種高度逼真的模擬人在自然環(huán)境中視、聽、動等行為的人機界面。圖形生成是虛擬現(xiàn)實技術的重要瓶頸。本文對面向虛擬現(xiàn)實的實時圖形生成技術及其發(fā)展情況作了詳細的介紹和綜述。其主要內(nèi)容是圖形生成的硬件體系結構以及在虛擬現(xiàn)實的真實感圖形生成中用于加速的各種有效技術。 虛擬現(xiàn)實技術是一門新興邊緣的技術，研究內(nèi)容涉及多個領域，應用十分廣泛，被公認為是21世紀重要的發(fā)展學科以及影響人們生活的重要技術之一。從虛擬現(xiàn)實的概念出發(fā)，對虛擬現(xiàn)實技術的國內(nèi)外研究現(xiàn)狀進行了充分論述，并展望了虛擬現(xiàn)實的發(fā)展趨勢。 “虛擬現(xiàn)實”就是一種可以創(chuàng)建和體驗虛擬世界的計算機系統(tǒng)。這種系統(tǒng)生成的各種虛擬環(huán)境，作用于用戶的視覺、聽覺、觸覺，使用戶產(chǎn)生身臨其境的感覺，沉浸其中。而所謂虛擬世界則是虛擬環(huán)境或給定仿真對象的集合虛擬現(xiàn)實是近年發(fā)展起來的一項新技術，目前已廣泛地應用于許多領域。該文闡述了虛擬現(xiàn)實技術的產(chǎn)生、概念、特征及其意義、虛擬現(xiàn)實技術的技術組成和藝術、情感魅力，分析了虛擬現(xiàn)實技術的研究內(nèi)容、方向和技術瓶頸。

關鍵詞：虛擬現(xiàn)實技術；虛擬環(huán)境；研究現(xiàn)狀 虛擬現(xiàn)實；關鍵元素；3I特征；通式；演變發(fā)展 虛擬現(xiàn)實；建模；繪制；人機交互；開發(fā)平臺 虛擬現(xiàn)實技術；分布式虛擬環(huán)境；交互技術；心理學 虛擬現(xiàn)實；虛擬環(huán)境；混合建模；幾何實體；光源照射；世界坐標系；用戶坐標系；虛擬物體；圖象合成；虛擬對象 虛擬現(xiàn)實；幾何建模；物理建模；行為建模 虛擬現(xiàn)實技術；發(fā)展過程；研究現(xiàn)狀 虛擬現(xiàn)實；圖形生成；圖形加速 虛擬現(xiàn)實；研究現(xiàn)況；發(fā)展趨勢 虛擬現(xiàn)實；交互技術；虛擬環(huán)境；沉浸；構想

虛擬現(xiàn)實技術的演變發(fā)展與展望

鄒湘軍，孫健，何漢武，等

來源出版物：系統(tǒng)仿真學報, 2004, 16 (9): 1905-32-1909

被引頻次：284

虛擬現(xiàn)實綜述

趙沁平

來源出版物：中國科學（F輯：信息科學）, 2009, 39(1): 2-46

被引頻次：233

展望虛擬現(xiàn)實技術

蘇建明，張續(xù)紅，胡慶夕

來源出版物：計算機仿真, 2004, 21(1): 18-21

被引頻次：179

虛擬現(xiàn)實中基于圖形與圖象的混合建模技術

李自力

來源出版物：中國圖象圖形學報：A 輯, 2001, 6(1): 96-101

被引頻次：177

虛擬現(xiàn)實中的建模方法

楊克儉，劉舒燕，陳定方

來源出版物：武漢理工大學學報, 2001, 23(6): 47-50

被引頻次：168

虛擬現(xiàn)實技術的發(fā)展過程及研究現(xiàn)狀

吳迪，黃文騫

來源出版物：海洋測繪, 2002, 22(6): 15-17

被引頻次：151

虛擬現(xiàn)實的圖形生成技術

劉學慧，吳恩華

來源出版物：中國圖象圖形學報：A 輯, 1997, 2(4): 205-212

被引頻次：150

虛擬現(xiàn)實技術的國內(nèi)外研究現(xiàn)狀與發(fā)展

許微

來源出版物：現(xiàn)代商貿(mào)工業(yè), 2009, 21(2): 279-280

被引頻次：149

虛擬現(xiàn)實技術概述

張占龍，羅辭勇，何為

來源出版物：計算機仿真, 2005, 22(3): 1-3

被引頻次：1097

來源出版物：IEEE Transactions on Neural Systems and Rehabilitation Engineering, 2001, 9(3): 308-318

被引頻次：228

Virtualized reality: Constructing virtual worlds from real scenes

Kanade, T; Rander, P; Narayanan, PJ; et al.

來源出版物：IEEE Multimedia, 1997 (1): 34-47

被引頻次：221

Virtual reality surgical simulator

Satava, RM

來源出版物：Surgical Endoscopy, 1993, 7(3): 203-205

被引頻次：217

Proficiency-based virtual reality training significantly reduces the error rate for residents during their first 10 laparoscopic cholecystectomies

Ahlberg, G; Enochsson, L; Gallagher, AG; et al.

來源出版物：The American Journal of Surgery, 2007, 193(6): 797-804

被引頻次：181

Virtual reality exposure therapy for Vietnam veterans with posttraumatic stress disorder

Rothbaum, BO; Hodges, LF; Ready, D; et al.

來源出版物：The Journal of Clinical Psychiatry, 2001, 62(8): 1, 478-622

被引頻次：181

Virtual bronchoscopy - Relationships of virtual reality endobronchial simulations to actual bronchoscopic findings

Vining, DJ; Liu, K; Choplin, RH; et al.

來源出版物：CHEST Journal, 1996, 109(2): 549-553

來源出版物：遼寧工程技術大學學報: 自然科學版, 2004, 23(2): 238-240

被引頻次：307

來源出版物：Nature Materials, 2003, 2(5): 301-306

被引頻次：1059

Self-cleaning surfaces - Virtual realities

Blossey, R

Abstract:In the 19th century, Oscar Wilde stated “We live, I regret to say, in an age of surfaces”. Today, we do so even more, and we do not regret it: key advances in the understanding and fabrication of surfaces with controlled wetting properties are about to make the dream of a contaminationfree (or ‘no-clean’) surface come true. Two routes to self-cleaning are emerging, which work by the removal of dirt by either film or droplet flow. Although a detailed understanding of the mechanisms underlying the behaviour of liquids on such surfaces is still a basic research topic, the first commercial products in the household-commodity sector and for applications in biotechnology are coming within reach of the marketplace. This progress report describes the current status of understanding of the underlying mechanisms, the concepts for making such surfaces, and some of their first applications. Objective: To demonstrate that virtual realitybook=27,ebook=31(VR) training transfers technical skills to the operating room (OR) environment.Summary Background Data: The use of VR surgical simulation to train skills and reduce error risk in the OR has never been demonstrated in a prospective, randomized, blinded study. Methods: Sixteen surgical residents (PGY 1–4) had baseline psychomotor abilities assessed, then were randomized to either VR training (MIST VR simulator diathermy task) until expert criterion levels established by experienced laparoscopists were achieved (n=8), or control non-VR-trained (n=8). All subjects performed laparoscopic cholecystectomy with an attending surgeon blinded to training status. Videotapes of gallbladder dissection were reviewed independently by two investigators blinded to subject identity and training, and scored for eight predefined errors for each procedure minute (interrater reliability of error assessment r>0.80). Results: No differences in baseline assessments were found between groups. Gallbladder dissection was 29% faster for VR-trained residents. Non-VR-trained residents were nine times more likely to transiently fail to make progress (P<0.007, Mann-Whitney test) and five times more likely to injure the gallbladder or burn nontarget tissue (chi-square=4.27, P<0.04). Mean errors were six times less likely to occur in the VR-trained group (1.19 vs. 7.38 errors per case; P<0.008, Mann-Whitney test). Conclusions: The use of VR surgical simulation to reach specific target criteria significantly improved the OR performance of residents during laparoscopic cholecystectomy. This validation of transfer of training skills from VR to OR sets the stage for more sophisticated uses of VR in assessment, training, error reduction, and certification of surgeons. BACKGROUND: This study examined the impact of virtual reality (VR) surgical simulation on improvement of psychomotor skills relevant to the performance of laparoscopic cholecystectomy. METHODS: Sixteen surgical trainees performed a laparoscopic cholecystectomy on patients in the operating room (OR). The participants were then randomized to receive VR training (ten repetitions of all six tasks on the Minimally Invasive Surgical Trainer-Virtual Reality (MIST-VR)) or no training. Subsequently, all subjects performed a further laparoscopic cholecystectomy in the OR. Both operative procedures were recorded on videotape, and assessed by two independent and blinded observers using predefined objective criteria. Time to complete the procedure, error score and economy of movement score were assessed during the laparoscopic procedure in the OR. RESULTS: No differences in baseline variables were found between the two groups. Surgeons who received VR training performed laparoscopic cholecystectomy significantly faster than the control group (P=0.021). Furthermore, those who had VR training showed significantly greater improvement in error (P=0.003) and economy of movement (P=0.003) scores. CONCLUSION: Surgeons who received VR simulator training showed significantly greater improvement in performance in the OR than those in the control group. VR surgical simulation is therefore a valid tool for training of laparoscopic psychomotor skills and could be incorporated into surgical training programmes. Summary Background Data: To inform surgeons about the practical issues to be considered for successful integration of virtual reality simulation into a surgical training program. The learning and practice of minimally invasive surgery (MIS) makes unique demands on surgical training programs. A decade ago Satava proposed virtual reality (VR) surgical simulation as a solution for this problem. Only recently have robust scientific studies supported that vision. Methods: A review of the surgical education, human-factor, and psychology literature to identify important factors which will impinge on the successful integration of VR training into a surgical training program. Results: VR is more likely to be successful if it is systematically integrated into a well-thought-out education and training program which objectively assesses technical skills improvement proximate to the learning experience. Validated performance metrics should be relevant to the surgical task being trained but in general will require trainees to reach an objectively determined proficiency criterion, based on tightly defined metrics and perform at this level consistently. VR training is more likely to bebook=28,ebook=32successful if the training schedule takes place on an interval basis rather than massed into a short period of extensive practice. High-fidelity VR simulations will confer the greatest skills transfer to the in vivo surgical situation, but less expensive VR trainers will also lead to considerably improved skills generalizations. Conclusions: VR for improved performance of MIS is now a reality. However, VR is only a training tool that must be thoughtfully introduced into a surgical training curriculum for it to successfully improve surgical technical skills. A personal computer (PC)-based desktop virtual reality (VR) system was developed for rehabilitating hand function in stroke patients. The system uses two input devices, a Cyber-Glove and a Rutgers Master U-ND (RMII) force feedback glove, allowing user interaction with a virtual environment. This consists of four rehabilitation routines, each designed to exercise one specific parameter of hand movement: range, speed, fractionation or strength. The use of performance-based target levels is designed to increase patient motivation and individualize exercise difficulty to a patient’s current state. Pilot clinical trials have been performed using the above system combined with noncomputer tasks, such as pegboard insertion or tracing of two-dimensional (2-D) patterns. Three chronic stroke patients used this rehabilitation protocol daily for two weeks. Objective measurements showed that each patient showed improvement on most of the hand parameters over the course of the training. Subjective evaluation by the patients was also positive. This technical report focuses on this newly developed technology for VR rehabilitation. A new visual medium, Virtualized Reality, immerses viewers in a virtual reconstruction of real-world events. The Virtualized Reality world model consists of real images and depth information computed from these images. Stereoscopic reconstructions provide a sense of complete immersion, and users can select their own viewpoints at view time, independent of the actual camera positions used to capture the event. The virtual-reality surgical simulator signals the beginning of an era of computer simulation for surgery. The surgical resident of the future will learn new perspectives on surgical anatomy and repeatedly practice surgical procedures until they are perfect before performing surgery on patients. Primitive though these initial steps are, they represent the foundation for an educational base that will be as important to surgery as the flight simulator is to aviation. It is anticipated that the full development of the surgical simulator will take less than the 40 years which was required for flight simulators to become an indispensable ingredient of pilot training. As the system evolves, many new and yet-to-be-imagined applications will arise, but we must have understanding and patience as we wait for computer power to improve to a point where VR surgical simulation can emerge from its PacMan era. Background: Virtual reality (VR) training has been shown previously to improve intraoperative performance during part of a laparoscopic cholecystectomy. The aim of this study was to assess the effect of proficiency-based VR training on the outcome of the first 10 entire cholecystectomies performed by novices.Methods: Thirteen laparoscopically inexperienced residents were randomized to either (1) VR training until a predefined expert level of performance was reached, or (2) the control group. Videotapes of each resident’s first 10 procedures were reviewed independently in a blinded fashion and scored for predefined errors. Results: The VR-trained groupbook=29,ebook=33consistently made significantly fewer errors (P=0.0037). On the other hand, residents in the control group made, on average, 3 times as many errors and used 58% longer surgical time. Conclusions: The results of this study show that training on the VR simulator to a level of proficiency significantly improves intraoperative performance during a resident’s first 10 laparoscopic cholecystectomies. Background: Virtual reality (VR) integrates real-time computer graphics, body-tracking devices, visual displays, and other sensory input devices to immerse a participant in a computer-generated virtual environment that changes in a natural way with head and body motion. VR exposure (VRE) is proposed as an alternative to typical imaginal exposure treatment for Vietnam combat veterans with posttraumatic stress disorder (PTSD). Method: This report presents the results of an open clinical trial using VRE to treat Vietnam combat veterans who have DSM-IV PTSD. In 8 to 16 sessions. 10 male patients were exposed to 2 virtual environments: A virtual Huey helicopter flying over a virtual Vietnam and a clearing surrounded by jungle. Results: Clinician-rated PTSD symptoms as measured by the Clinician Administered PTSD Scale, the primary outcome measure, at 6-month follow-up indicated an overall statistically significant reduction from baseline (P=0.0021) in symptoms associated with specific reported traumatic experiences. All 8 participants interviewed at the 6-month follow-up reported reductions in PTSD symptoms ranging from 15% to 67%. Significant decreases were seen in all 3 symptom clusters (P<0.02). Patient self-reported intrusion symptoms as measured by the Impact of Event Scale were significantly lower (P<0.05) at 3 months than at baseline but not at 6 months. although there was a clear trend toward fewer intrusive thoughts and somewhat less avoidance. Conclusion: Virtual reality exposure therapy holds promise for treating PTSD in Vietnam veterans. Advances in computer technology have permitted development of virtual reality images of the tracheobronchial tree using data sets derived from helical CT of the chest. To determine the relevance of these images to actual bronchoscopic findings, we compared “virtual bronchoscopy”images with videotaped bronchoscopy results in 20 patients who had undergone both helical chest CT and fiberoptic bronchoscopy during clinical evaluation of their thoracic problems. Suboptimal endobronchial simulations in ten patients identified important, readily-addressed technical requirements for this imaging procedure. In the ten patients with technically suitable renderings of the airway, virtual bronchoscopy simulations accurately demonstrated endobronchial obstructions by tumor in five, airway distortion and/or ectasia in four, and accessory bronchi in another. These preliminary observations suggest that virtual bronchoscopy simulations accurately represent major endobronchial anatomic findings. This technique may have a role in prebronchoscopy planning, endoscopy training, and/or endobronchial therapy, and merits further study.

Virtual reality training improves operating room performance - Results of a randomized, double-blinded study

Seymour, NE; Gallagher, AG; Roman, SA; et al.

來源出版物：Annals of Surgery, 2002, 236(4): 458-464

被引頻次：539

Randomized clinical trial of virtual reality simulation for laparoscopic skills training

Grantcharov, TP; Kristiansen, VB; Bendix, J; et al.

來源出版物：British Journal of Surgery, 2004, 91(2): 146-150

被引頻次：335

Virtual reality simulation for the operating room -Proficiency-based training as a paradigm shift in surgical skills training

Gallagher, AG; Ritter, EM; Champion, H; et al.

來源出版物：Annals of Surgery, 2005, 241(2): 364-372

被引頻次：230

Virtual reality-enhanced stroke rehabilitation

Jack, D; Boian, R; Merians, AS; et al.

Keywords:Cyber Glove; haptic glove; rehabilitation; Rutgers Master II-ND; stroke; virtual reality (VR) computer-assisted diagnosis; computer simulation; bronchoscopy; lung neoplasms; tomography, x-ray computed