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FEM analysis of deepwater drilling risers under the operability and hang-off working conditions 被引量:10
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作者 戴伟 高峰 白勇 《Journal of Marine Science and Application》 2009年第2期156-162,共7页
In recent years, numerous exploration activities of oil and gas industry have been conducted in ultra deep water. The global offshore industry is building systems today for drilling in even deeper water, progressively... In recent years, numerous exploration activities of oil and gas industry have been conducted in ultra deep water. The global offshore industry is building systems today for drilling in even deeper water, progressively using new technologies, and significantly extending existing technologies. This is the general trend in the offshore oil and gas industry. So the technology of ultra-deepwater risers, which is the main tool in drilling oil, is more and more standard. This paper manly focuses on the global analysis of the drilling risers. And it is divided into two parts, operability analysis and hang-off analysis that are used to check the design of the riser. In this paper, the rotation angle and stress of the riser in the drilling mode are calculated to determine the operability envelop. The number of the buoyancy modules has been determined and according to the API standard, all the worked out values have been checked out. From all the above, it is concluded that the operability envelop is relatively small under harsh condition and the number of the buoyancy modules is a little large. And above all, the design of this riser is successful. 展开更多
关键词 drilling riser operability hang-off FEM analysis
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IoT Data and Device Interoperability with TIPPSS for Connected Vehicles
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《China Standardization》 2024年第4期59-59,共1页
With the integration of sophisticated technologies and increased data connectivity,the value of a car is no longer confined to just transportation-it is also a hub of personal and operational data.This change naturall... With the integration of sophisticated technologies and increased data connectivity,the value of a car is no longer confined to just transportation-it is also a hub of personal and operational data.This change naturally leads to cybersecurity challenges from remote hacking,to breach of data privacy,and potential physical safety concerns as operational functions of a vehicle are highly vulnerable.Making IoTs interoperable,secure and private can be achieved using the framework of the existing IEEE P2933-Draft Standard for Clinical Internet of Things(IoT)Data and Device Interoperability with TIPPSS-Trust,Identity,Privacy,Protection,Safety,Security.This workshop will bring together professionals from technology developers in software,firmware,and devices;automotive manufacturing,regulatory,researchers and other related stakeholders to understand the needs for TIPPSS for IoTs in connected vehicles and the related use case requirements. 展开更多
关键词 IOT OPERATIONAL VALUE
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Numerical Investigation on Effect of Vapor Split Ratio to Performance and Operability for Dividing Wall Column 被引量:4
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作者 Laleh Torab Maralani 袁希钢 +2 位作者 罗祎青 龚超 余国琮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2013年第1期72-78,共7页
Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed f... Operability problem of dividing wall column (DWC) raised by vapor split was investigated by numerically analyzing four cases defined by different compositions of a three-component mixture. DWCs were firstly designed for each case by optimizing the vapor split to the two sides of the dividing wall, and then their feasibilities and total annual costs in operation were evaluated against different vapor split ratios. The analysis on the operability of the DWC for four cases was made based on two scenarios: (1) vapor split is shifted by the vapor resistance difference between the column sections in the two sides of the dividing wall and (2) the feed composition is changed. It was demonstrated that the positioning of the dividing wall and the decision on the vapor split may affect significantly the operability of a DWC. 展开更多
关键词 dividing wall column vapor split ratio operability
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Elevating the flexibility and operability of dividing-wall distillation columns via feed thermal condition adjustment
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作者 Yang Yuan Kejin Huang +3 位作者 Liang Zhang Haisheng Chen Shaofeng Wang Yingjie Jiao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第7期947-954,共8页
Because of the complicated interplay between the prefractionator and main distillation column involved,the black-hole problem might occur and prohibit the assignment of four specifications to dividing-wall distillatio... Because of the complicated interplay between the prefractionator and main distillation column involved,the black-hole problem might occur and prohibit the assignment of four specifications to dividing-wall distillation columns(DWDCs)(e.g., the three main product compositions plus an impurity ratio in the intermediate product), which lowers terribly process flexibility and operability. In this paper, a feed thermal condition adjustment strategy, achieved by the installation of a pre-heater in feed pipeline, is employed to eliminate the black-hole problem and serve to enhance process flexibility and operability. Through the strong influence to the overall mass and energy balance of the DWDC, the feed thermal condition adjustment can alter the interlinking flows between the thermally coupled prefractionator and main distillation column and work effectively to coordinate their relationship. A DWDC separating a benzene, toluene, and o-xylene mixture is chosen to ascertain the feasibility of the philosophy proposed. The static and dynamic studies demonstrate that the feed thermal condition adjustment is an effective way to refine process design and can completely eliminate the black-hole problem and elevate consequently process flexibility and operability. 展开更多
关键词 DWDC Process flexibility Process operability Black-hole problem Feed thermal condition
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Investigation of the operability for four-product dividing wall column with two partition walls
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作者 Xiaolong Ge Botong Liu +2 位作者 Botan Liu Hongxing Wang Xigang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1670-1676,共7页
For separating some specific four component mixtures into four products, the four-product dividing wall column(FPDWC) with two partition walls can provide the same utility consumption with the extended Petlyuk configu... For separating some specific four component mixtures into four products, the four-product dividing wall column(FPDWC) with two partition walls can provide the same utility consumption with the extended Petlyuk configuration, although with structure simplicity. However, the reluctance to implement this kind of four product dividing wall column industrially also consists in the two uncontrollable vapor splits associated with it. The vapor split ratios are set at the design stage and might not be the optimal value for changed feed composition, thus minimum energy consumption could not be ensured. In the present work, a sequential iterative optimization approach was initially employed to determine the parameters of cost-effective FPDWC. Then the effect of maintaining the vapor split ratios at their nominal value on the energy penalty was investigated for the FPDWC with two partition walls, in case of feed composition disturbance. The result shows that no more than + 2% above the optimal energy requirements could be ensured for 20% feed composition disturbances, which is encouraging for industrial implementation. 展开更多
关键词 DISTILLATION Four-product dividing wall column Vapor split operability
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The Effects of Touch Button Size on Touchscreen Operability
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作者 Jinghong Xiong Satoshi Muraki Kiyotaka Fukumoto 《Journal of Mechanics Engineering and Automation》 2014年第8期667-672,共6页
The present study investigated the effects of touch button size on touchscreen operability and compared these effects between young adult and elderly participants. A total of 21 young adults (aged 22.3 ± 1.5 ye... The present study investigated the effects of touch button size on touchscreen operability and compared these effects between young adult and elderly participants. A total of 21 young adults (aged 22.3 ± 1.5 years) and 20 elderly adults (aged 68.1 ±4.9 years) were recruited and asked to press square number buttons (from 0 to 9) on an experimental touchscreen with their right index finger. The buttons' size changed during the experiment with six conditions (6, 8, 10, 12, 14 and 16 mm). It was found that a decrease of the button size to l0 mm or below tended to increase the operation time and error rate, whereas it decreased the subjective overall operability of the touchscreen. Such effects were greater in the elderly adults than in the young adults. In addition, the reaction positions on the buttons were found to be close to the right side of them, which led the fingertip to approach the right outline of the buttons. These findings suggest that the use of small touch buttons should be minimised on touchscreens, especially for elderly users. 展开更多
关键词 Touchscreen button size operability elderly.
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Transesophageal ultrasonography in assessment of operability for advanced esophageal carcinoma
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作者 段云友 贺声 +4 位作者 曹铁生 张少玲 黄裕新 张广忖 程庆书 《Journal of Medical Colleges of PLA(China)》 CAS 1994年第4期294-297,共4页
Sixty-one intermediate and advanced esophageal carcinoma patients were examined by transesophageal ultrasonography(TEUS),including 53 squamous carcinomas and 8 adenocarcinomas. The ultrasonic images showed that there ... Sixty-one intermediate and advanced esophageal carcinoma patients were examined by transesophageal ultrasonography(TEUS),including 53 squamous carcinomas and 8 adenocarcinomas. The ultrasonic images showed that there were clearly demarcated spaces between the tumours and the important adjacent structures in 42 out of 48 patients having undergone esophagectomy,while in 10 non-resectable patients,the ultrasonic images displayed an unclear demarcation between the tumours and thoracic aorta,pulmonary vein and pericardium. The study discovered that the regional echo of thoracic aortic wall was interrupted and replaced by tumour hypoecho, and the aorta pressed,indicating carcinoma's serious invasion of the aorta. The non-resectability of carcinoma of this kind was later confirmed in operation. On 3 cases,operations couldn't be performed due to metastasis of liver.Six cases failed to be accurately assessed owing to the impassability for probe caused by esophageal stenosis or other factors. Accuracy of assessment was 85. 2%. So we believe TEUS is a useful,simple,reliable and secure method for assessing operability of esophageal carcinoma. 展开更多
关键词 TRANSESOPHAGEAL ULTRASONOGRAPHY ESOPHAGEAL NEOPLASMS operable ASSESSMENT
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Reactive power operability of distributed energy resources for voltage stability of distribution networks 被引量:2
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作者 Shuai HU Yue XIANG +3 位作者 Xin ZHANG Junyong LIU Rui WANG Bowen HONG 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2019年第4期851-861,共11页
The penetration level of distributed energy resources(DERs)is increasing and has significant impact on the voltage stability of distribution networks.Based on the various types of DERs with distinct reactive power cha... The penetration level of distributed energy resources(DERs)is increasing and has significant impact on the voltage stability of distribution networks.Based on the various types of DERs with distinct reactive power characteristics(RPC),their different contributions to the system voltage stability require classification.Firstly,the features of DERs are reviewed and classified based on their RPC,to investigate different distributed generation technologies for reactive power support in distribution networks.Then,the concept of a relative available transmission capacity index(RATCI),which is based on power transfer margin of the power-voltage curve considering the non-negligible distribution network resistance,is proposed to quantify and evaluate the voltage stability by integrating DERs with the defined reactive power types.Case studies have been conducted for an IEEE 33-bus distribution network to calculate the system RATCI for the mixed integration of DERs.Results show that the multitype and multi-locational integration of DERs can improve the voltage stability of a distribution network. 展开更多
关键词 Voltage stability Distributed ENERGY resource(DER) Distribution network RELATIVE available transmission capacity REACTIVE power operability RENEWABLE ENERGY integration
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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage
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作者 Yan Zhao Qiang Yuan +5 位作者 Liting Yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期348-360,共13页
Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(gen... Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term cyclability.Here,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical properties.During Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O movement.Such superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries. 展开更多
关键词 NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization
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A Review on TSO-DSO Data Exchange,CIM Extensions and Interoperability Aspects
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作者 Arsim Bytyqi Siddhesh Gandhi +1 位作者 Eric Lambert Nejc Petrovic 《Journal of Modern Power Systems and Clean Energy》 SCIE EI CSCD 2022年第2期309-315,共7页
The exchange of information between transmission system operators(TSOs)and distribution system operators(DSOs)is a common practice.However,the evolution of the regulatory frameworks in Europe has increased the need fo... The exchange of information between transmission system operators(TSOs)and distribution system operators(DSOs)is a common practice.However,the evolution of the regulatory frameworks in Europe has increased the need for enhancing TSO-DSO data exchange and interoperability.This paper provides an overview of the TSO-DSO data exchanges and demonstrates the best practices using International Electrotechnical Commission(IEC)common information model(CIM),including the implementation of IEC common grid model exchange standard(CGMES),and discussion of the corresponding advantages,disadvantages,and challenges.Furthermore,this paper evaluates and reports the activities already carried out within European projects,with particular focus on TSO-DSO interoperability.Finally,this paper concludes the need for TSOs and DSOs to rely on standard-based solutions when performing TSO-DSO data exchange,which enables the efficient operation and development of the future power systems. 展开更多
关键词 Transmission system operator(TSO) distribution system operator(DSO) data exchange INTERoperability STANDARDIZATION common information model(CIM) common grid model exchange standard(CGMES)
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低温等离子治疗儿童鼻咽部第二鳃裂囊肿分析
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作者 温鑫 黄爱萍 +5 位作者 张爱英 许敏 宋英鸾 崔莉 耿江桥 史静 《中国耳鼻咽喉头颈外科》 CSCD 2024年第1期54-56,共3页
目的探讨儿童鼻咽部第二鳃裂囊肿的临床特征和治疗方式,提高诊治能力。方法回顾性分析河北省儿童医院收治的4例儿童鼻咽部第二鳃裂囊肿的临床资料,包括年龄、性别、症状、影像学资料和治疗过程。总结分析病变部位特点,B超、CT或MRI特征... 目的探讨儿童鼻咽部第二鳃裂囊肿的临床特征和治疗方式,提高诊治能力。方法回顾性分析河北省儿童医院收治的4例儿童鼻咽部第二鳃裂囊肿的临床资料,包括年龄、性别、症状、影像学资料和治疗过程。总结分析病变部位特点,B超、CT或MRI特征,术后病理结果及治疗方式。结果4例鼻咽部第二鳃裂囊肿患儿均表现为鼻咽侧壁咽鼓管咽口与腭咽弓后上方连线上的囊性肿物,囊壁较厚,影像学检查结果均为囊性病变。4例患儿选择内镜下低温等离子病变切除术,其中2例为内侧囊壁大部分切除术,将囊腔充分敞开,2例为囊肿全部切除术。术后病理提示衬覆纤毛柱状上皮或复层上皮,周围淋巴组织增生。术后随访1.5~3年无复发。结论儿童鼻咽部第二鳃裂囊肿临床罕见,诊断主要依靠病变部位及术后病理结果,内镜下低温等离子切除病变组织是微创、安全、有效的治疗方式。 展开更多
关键词 儿童(Child) 外科手术(Surgical Procedures Operative) 鼻咽部第二鳃裂囊肿(nasopharyngeal cyst of second branchial cleft) 低温等离子(low temperature plasma)
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吸入性烧伤导致的喉气管狭窄疗效分析
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作者 邢园 郭志华 《中国耳鼻咽喉头颈外科》 CSCD 2024年第10期668-671,共4页
目的探讨成年人吸入性烧伤导致喉气管狭窄的外科治疗方法和效果。方法回顾性分析2008年9月~2022年3月就诊于西安交通大学附属红会医院,由吸入性烧伤导致的16例喉气管狭窄患者临床资料,男10例,女6例,年龄17~57岁,平均38.4岁。支撑喉镜下... 目的探讨成年人吸入性烧伤导致喉气管狭窄的外科治疗方法和效果。方法回顾性分析2008年9月~2022年3月就诊于西安交通大学附属红会医院,由吸入性烧伤导致的16例喉气管狭窄患者临床资料,男10例,女6例,年龄17~57岁,平均38.4岁。支撑喉镜下喉剪或激光切除瘢痕并球囊扩张4例;气道前壁加宽喉气管重建术9例,其中肋软骨加宽4例,肌皮瓣2例,甲状软骨翼板3例;气管-气管端端吻合1例,环气管吻合1例,甲状软骨气管吻合1例。结果拔管13例,拔管率81.25%(13/16),失败3例,失败率为18.75%(3/16)。T型硅胶管放置时间为9~24个月,平均12.5个月。随访3个月~10年,所有拔管者均未见复发,进食、呼吸正常。结论对于成年人吸入性烧伤导致的喉气管狭窄患者进行气道重建选择好恰当的手术时机及对应的手术方法,效果满意,T型管放置时间要长。 展开更多
关键词 烧伤 吸入性(Burns Inhalation) 喉狭窄(Laryngostenosis) 气管狭窄(Tracheal Stenosis) 外科手术(Surgical Procedures Operative) 治疗结果(Treatment Outcome)
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The Way to Optimize the Right to Personal Data Portability in Chinese Practice——Based on Empirical Analysis of the Privacy Policies of 66 Mobile Apps
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作者 LI Jinhua 《The Journal of Human Rights》 2024年第3期637-661,共25页
Although the existing legal norms and judicial practic-es can provide basic guidance for the right to personal data portabili-ty, it can be concluded that there are obstacles to the realization of this right through e... Although the existing legal norms and judicial practic-es can provide basic guidance for the right to personal data portabili-ty, it can be concluded that there are obstacles to the realization of this right through empirical research of the privacy policies of 66 mobile apps, such as whether they have stipulations on the right to personal data portability, whether they are able to derive copies of personal in-formation automatically, whether there are textual examples, whether ID verification is required, whether the copied documents are encrypt-ed, and whether the scope of personal information involved is consis-tent. This gap in practice, on the one hand, reflects the misunderstand-ing of the right to personal data portability, and on the other hand, is a result of the negative externalities, practical costs and technical lim-itations of the right to personal data portability. Based on rethinking the right to data portability, we can somehow solve practical problems concerning the right to personal data portability through multiple measures such as promoting the fulfillment of this right by legislation, optimizing technology-oriented operations, refining response process mechanisms, and enhancing system interoperability. 展开更多
关键词 right to personal data portability right to consulta-tion and duplication right to data transfer privacy policy techni-cal operability
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利多卡因在部分肿瘤微创手术加速康复外科中的应用进展
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作者 赵家慧(综述) 韩永正(审校) +1 位作者 李民(审校) 刘畅(审校) 《中国微创外科杂志》 CSCD 北大核心 2024年第8期569-573,共5页
随着微创手术技术的不断发展,加速康复外科(enhanced recovery after surgery,ERAS)理念在癌症患者围手术期深入推广,如何通过合理用药,缓解肿瘤患者围手术期疼痛,减轻应激反应,减少阿片类药物的使用或实现无阿片类药物麻醉(opioid-free... 随着微创手术技术的不断发展,加速康复外科(enhanced recovery after surgery,ERAS)理念在癌症患者围手术期深入推广,如何通过合理用药,缓解肿瘤患者围手术期疼痛,减轻应激反应,减少阿片类药物的使用或实现无阿片类药物麻醉(opioid-free anesthesia,OFA),降低术后恶心呕吐(post operative nausea and vomiting,PONV)及认知功能障碍发生率,保护肺功能及胃肠道功能,加速康复,成为麻醉领域研究热点。 展开更多
关键词 加速康复外科 阿片类药物 胃肠道功能 利多卡因 微创手术 OPERATIVE 合理用药
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Computational Experiments for Complex Social Systems:Integrated Design of Experiment System 被引量:2
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作者 Xiao Xue Xiangning Yu +4 位作者 Deyu Zhou Xiao Wang Chongke Bi Shufang Wang Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第5期1175-1189,共15页
Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the ... Powered by advanced information industry and intelligent technology,more and more complex systems are exhibiting characteristics of the cyber-physical-social systems(CPSS).And human factors have become crucial in the operations of complex social systems.Traditional mechanical analysis and social simulations alone are powerless for analyzing complex social systems.Against this backdrop,computational experiments have emerged as a new method for quantitative analysis of complex social systems by combining social simulation(e.g.,ABM),complexity science,and domain knowledge.However,in the process of applying computational experiments,the construction of experiment system not only considers a large number of artificial society models,but also involves a large amount of data and knowledge.As a result,how to integrate various data,model and knowledge to achieve a running experiment system has become a key challenge.This paper proposes an integrated design framework of computational experiment system,which is composed of four parts:generation of digital subject,generation of digital object,design of operation engine,and construction of experiment system.Finally,this paper outlines a typical case study of coal mine emergency management to verify the validity of the proposed framework. 展开更多
关键词 artificial SYSTEM operations
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Dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates 被引量:2
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作者 Yuncheng Liu Ke Xu +4 位作者 Xuhao Fan Xinger Wang Xuan Yu Wei Xiong Hui Gao 《Opto-Electronic Advances》 SCIE EI CAS CSCD 2024年第1期36-46,共11页
Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,... Interactive holography offers unmatched levels of immersion and user engagement in the field of future display.Despite of the substantial progress has been made in dynamic meta-holography,the realization of real-time,highly smooth interactive holography remains a significant challenge due to the computational and display frame rate limitations.In this study,we introduced a dynamic interactive bitwise meta-holography with ultra-high computational and display frame rates.To our knowledge,this is the first reported practical dynamic interactive metasurface holographic system.We spa-tially divided the metasurface device into multiple distinct channels,each projecting a reconstructed sub-pattern.The switching states of these channels were mapped to bitwise operations on a set of bit values,which avoids complex holo-gram computations,enabling an ultra-high computational frame rate.Our approach achieves a computational frame rate of 800 kHz and a display frame rate of 23 kHz on a low-power Raspberry Pi computational platform.According to this methodology,we demonstrated an interactive dynamic holographic Tetris game system that allows interactive gameplay,color display,and on-the-fly hologram creation.Our technology presents an inspiration for advanced dynamic meta-holography,which is promising for a broad range of applications including advanced human-computer interaction,real-time 3D visualization,and next-generation virtual and augmented reality systems. 展开更多
关键词 interactive display meta-holography bitwise operation ultra-high frame rate
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Effects of spot size on the operation mode of Ga As photoconductive semiconductor switch employing extrinsic photoconductivity 被引量:1
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作者 韦金红 李嵩 +5 位作者 陈红 曾凡正 贾成林 付泽斌 葛行军 钱宝良 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第5期91-99,共9页
To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insul... To guide the illuminating design to improve the on-state performances of gallium arsenide(GaAs)photoconductive semiconductor switch(PCSS),the effect of spot size on the operation mode of GaAsPCSS based on a semi-insulating wafer with a thickness of 1 mm,triggered by a 1064-nm extrinsic laser beam with the rectangular spot,has been investigated experimentally.It is found that the variation of the spot size in length and width can act on the different parts of the output waveform integrating the characteristics of the linear and nonlinear modes,and then significantly boosts the PCSS toward different operation modes.On this basis,a two-channel model containing the active and passive parts is introduced to interpret the relevant influencing mechanisms.Results indicate that the increased spot length can peak the amplitude of static domains in the active part to enhance the development of the nonlinear switching,while the extended spot width can change the distribution of photogenerated carriers on both parts to facilitate the linear switching and weaken the nonlinear switching,which have been proved by comparing the domain evolutions under different spot sizes. 展开更多
关键词 GaAs PCSS operation mode spot size on-state performances two-channel model domain evolution
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Fractal Fractional Order Operators in Computational Techniques for Mathematical Models in Epidemiology 被引量:1
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作者 Muhammad Farman Ali Akgül +2 位作者 Mir Sajjad Hashemi Liliana Guran Amelia Bucur 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1385-1403,共19页
New fractional operators, the COVID-19 model has been studied in this paper. By using different numericaltechniques and the time fractional parameters, the mechanical characteristics of the fractional order model arei... New fractional operators, the COVID-19 model has been studied in this paper. By using different numericaltechniques and the time fractional parameters, the mechanical characteristics of the fractional order model areidentified. The uniqueness and existence have been established. Themodel’sUlam-Hyers stability analysis has beenfound. In order to justify the theoretical results, numerical simulations are carried out for the presented methodin the range of fractional order to show the implications of fractional and fractal orders.We applied very effectivenumerical techniques to obtain the solutions of themodel and simulations. Also, we present conditions of existencefor a solution to the proposed epidemicmodel and to calculate the reproduction number in certain state conditionsof the analyzed dynamic system. COVID-19 fractional order model for the case of Wuhan, China, is offered foranalysis with simulations in order to determine the possible efficacy of Coronavirus disease transmission in theCommunity. For this reason, we employed the COVID-19 fractal fractional derivative model in the example ofWuhan, China, with the given beginning conditions. In conclusion, again the mathematical models with fractionaloperators can facilitate the improvement of decision-making for measures to be taken in the management of anepidemic situation. 展开更多
关键词 COVID-19 model fractal-fractional operator Ulam-Hyers stability existence and uniqueness numerical simulation
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建筑全生命周期碳排放——内涵、计算和减量 被引量:1
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作者 Zujian Huang Hao Zhou +3 位作者 Zhijian Miao Hao Tang Borong Lin Weimin Zhuang 《Engineering》 SCIE EI CAS CSCD 2024年第4期115-139,共25页
The life-cycle assessment method,which originates from general products and services,has gradually come to be applied to investigations of the life-cycle carbon emissions(LCCE)of buildings.A literature review was cond... The life-cycle assessment method,which originates from general products and services,has gradually come to be applied to investigations of the life-cycle carbon emissions(LCCE)of buildings.A literature review was conducted to clarify LCCE implications,calculations,and reductions in the context of buildings.A total of 826 global building carbon emission calculation cases were obtained from 161 studies based on the framework of the building life-cycle stage division stipulated by ISO 21930 and the basic principles of the emission factor(EF)approach.The carbon emission calculation methods and results are discussed herein,based on the modules of production,construction,use,end-of-life,and supplementary benefits.According to the hotspot distribution of a building’s carbon emissions,carbon reduction strategies are classified into six groups for technical content and benefits analysis,including reducing the activity data pertaining to building materials and energy,reducing the carbon EFs of the building materials and energy,and exploiting the advantages of supplementary benefits.The research gaps and challenges in current building LCCE studies are summarized in terms of research goals and ideas,calculation methods,basic parameters,and carbon reduction strategies;development suggestions are also proposed. 展开更多
关键词 Building carbon emissions Embodied carbon emissions Operational carbon emissions System boundary Activity data Carbon emission factor Life-cycle assessment Carbon reduction
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Novel Investigation of Stochastic Fractional Differential Equations Measles Model via the White Noise and Global Derivative Operator Depending on Mittag-Leffler Kernel 被引量:1
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作者 Saima Rashid Fahd Jarad 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2289-2327,共39页
Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this p... Because of the features involved with their varied kernels,differential operators relying on convolution formulations have been acknowledged as effective mathematical resources for modeling real-world issues.In this paper,we constructed a stochastic fractional framework of measles spreading mechanisms with dual medication immunization considering the exponential decay and Mittag-Leffler kernels.In this approach,the overall population was separated into five cohorts.Furthermore,the descriptive behavior of the system was investigated,including prerequisites for the positivity of solutions,invariant domain of the solution,presence and stability of equilibrium points,and sensitivity analysis.We included a stochastic element in every cohort and employed linear growth and Lipschitz criteria to show the existence and uniqueness of solutions.Several numerical simulations for various fractional orders and randomization intensities are illustrated. 展开更多
关键词 Measles epidemic model Atangana-Baleanu Caputo-Fabrizio differential operators existence and uniqueness qualitative analysis Newton interpolating polynomial
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