- 标题
- 摘要
- 关键词
- 实验方案
- 产品
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Switchable, widely tunable and Interval-Adjustable multi-wavelength erbium-doped fiber laser based on cascaded filters
摘要： The High Efficiency Video Coding (HEVC) standard (ITU-T H.265 and ISO/IEC 23008-2) has been developed with the main goal of providing significantly improved video compression compared with its predecessors. In order to evaluate this goal, verification tests were conducted by the Joint Collaborative Team on Video Coding of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29. This paper presents the subjective and objective results of a verification test in which the performance of the new standard is compared with its highly successful predecessor, the Advanced Video Coding (AVC) video compression standard (ITU-T H.264 and ISO/IEC 14496-10). The test used video sequences with resolutions ranging from 480p up to ultra-high definition, encoded at various quality levels using the HEVC Main profile and the AVC High profile. In order to provide a clear evaluation, this paper also discusses various aspects for the analysis of the test results. The tests showed that bit rate savings of 59% on average can be achieved by HEVC for the same perceived video quality, which is higher than a bit rate saving of 44% demonstrated with the PSNR objective quality metric. However, it has been shown that the bit rates required to achieve good quality of compressed content, as well as the bit rate savings relative to AVC, are highly dependent on the characteristics of the tested content.
关键词： standards,MPEG-H Part 2,Moving Picture Experts Group (MPEG),Video Coding Experts Group (VCEG),High Efficiency Video Coding (HEVC),H.265,Advanced Video Coding (AVC),Joint Collaborative Team on Video Coding (JCT-VC),video compression
更新于2025-09-23 15:19:57
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Performance of Solar Absorption-Subcooled Compression Hybrid Cooling System for Different Flow Rates of Hot Water
摘要： The solar absorption-subcooled compression hybrid cooling system (SASCHCS) is tech-economically feasible for high-rise buildings. Since such a system operates with no auxiliary heat source, the performance coupling of its absorption subsystem and solar collectors is sensitive to the variation of hot water ?ow rate. In this regard, the relationship of system performance and hot water ?ow rate is required to be clari?ed exactly. Therefore, this paper aims to illustrate the e?ect mechanism of hot water ?ow rate and to propose the corresponding decision criterion. The case study is based on a typical high-rise o?ce building in subtropical Guangzhou. The daily working process of this system with di?erent hot water ?ow rates is simulated and analyzed. Subsequently, the useful heat of collectors and cooling capacity of the absorption subsystem with the hot water ?ow rate is discussed in detail. The results show that the SASCHCS operates with hot water temperatures ranging from 60 C to 90 C. The energy saving increases with the rise of hot water ?ow rate, but such variation tends to be ?at for the excessively high ?ow rate. As the collector ?ow rate increases from 1 m3/h to 10 m3/h, the daily energy saving improves by 21% in August. Similarly, the daily energy saving increases by 37.5% as generator hot water ?ow rate increases from 1 m3/h to 10 m3/h. In addition, the collector ?ow rate of 3.6 m3/h (13.33 (kg/m2 h)) and the generator ?ow rate of 5.2 m3/h (19.26 (kg/m2 h)) are optimal for the annual operation, with considering power consumption of water pumps. This paper is helpful for the improvement of SASCHCS operating performance.
关键词： solar cooling,subcooled compression,hot water ?ow rate,absorption chiller,hybrid system
更新于2025-09-23 15:19:57
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Disparities selection controlled by the compensated image quality for a given bitrate
摘要： A stereoscopic image consists of two views rendering a depth sense. Indeed each eye is constrained to look at one view, and the small objects displacements across the two views are interpreted as an indication of depth. These displacements are exploited as speci?c inter-view redundancies from a compression viewpoint. The classical still compression scheme, called disparity-compensated compression scheme, compresses one view independently of the second view, and a block-based disparity map modeling the displacements is losslessly compressed. The difference between the original view and its disparity predicted view is then compressed and used by the decoder to compute the compensated view to improve the disparity predicted view. However, a proof of concept work has already shown that selecting disparities according to the compensated view, instead of the predicted view, yields increased rate-distortion performance. This paper derives from the JPEG-coder, a disparity-dependent analytic expression of the distortion induced by the compensated view. This expression is embedded into an algorithm with a reasonable numerical complexity approaching the performance obtained with the proof of concept work. The proposed algorithm, called fast disparity-compensated block matching algorithm, provides at the same bitrate an average performance increase as compared to the classical stereoscopic image coding schemes.
关键词： Stereoscopic image,Compression,Block matching algorithm,Disparity compensation,JPEG-distortion
更新于2025-09-23 15:19:57
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[IEEE 2019 16th China International Forum on Solid State Lighting & 2019 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS) - Shenzhen, China (2019.11.25-2019.11.27)] 2019 16th China International Forum on Solid State Lighting & 2019 International Forum on Wide Bandgap Semiconductors China (SSLChina: IFWS) - A Comparative Study of the Lifetimes of High-End and Low-Cost Off-Line LED Drivers Under Accelerated Test Conditions
摘要： In this paper, we present the following quantum compression protocol ‘P ’: Let ρ, σ be quantum states, such that S (ρ(cid:2)σ ) def= Tr(ρ log ρ ? ρ log σ ), the relative entropy between ρ and σ , is finite. Alice gets to know the eigendecomposition of ρ. Bob gets to know the eigendecomposition of σ . Both Alice and Bob know S (ρ(cid:2)σ ) and an error parameter ε. Alice and Bob use shared entanglement and after communication of O((S(ρ(cid:2)σ ) + 1)/ε4) bits from Alice to Bob, Bob ends up with a quantum state ?ρ, such that F(ρ, ?ρ) ≥ 1 ? 5ε, where F(·) represents fidelity. This result can be considered as a non-commutative generalization of a result due to Braverman and Rao where they considered the special case when ρ and σ are classical probability distributions (or commute with each other) and use shared randomness instead of shared entanglement. We use P to obtain an alternate proof of a direct-sum result for entanglement assisted quantum one-way communication complexity for all relations, which was first shown by Jain et al.. We also present a variant of protocol P in which Bob has some side information about the state with Alice. We show that in such a case, the amount of communication can be further reduced, based on the side information that Bob has. Our second result provides a quantum analog of the widely used classical correlated-sampling protocol. For example, Holenstein used the classical correlated-sampling protocol in his proof of a parallel-repetition theorem for two-player one-round games.
关键词： quantum communication complexity,compression protocols,correlated sampling,Quantum information theory,direct sum results
更新于2025-09-23 15:19:57
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Effect of Hot Water Setting Temperature on Performance of Solar Absorption-Subcooled Compression Hybrid Cooling Systems
摘要： The solar absorption-subcooled compression hybrid cooling system (SASCHCS) displays outstanding advantages in high-rise buildings. Since the performance coupling of collectors and absorption subsystems is stronger due to the absence of backup heat and the effect of generator setting temperature has not been realized adequately, it is highly important to study the relationship of SASCHCS operation and the set point temperature of hot water to prevent performance deterioration by inappropriate settings. Therefore, the paper mainly deals with the effect of collector and generator setting temperature. The investigation was based on the entire cooling period of a typical high-rise office building in subtropical Guangzhou. The off-design model of hybrid systems was built at first. Subsequently, the impact mechanism of setting temperature in two hot water cycles on facility operation was analyzed. It was found that the excessive rise of collector setting temperature deteriorated the energy saving, while the appropriate improvement of generator set point temperature was beneficial for the solar cooling. Besides, global optimization by the genetic algorithm displayed that 71.6°C for the collector setting temperature with 64.5°C for the generator was optimal for annual operation. The paper is helpful in enhancing the operation performance of SASCHCS.
关键词： setting temperature of hot water,solar cooling,subcooled compression,absorption chiller,hybrid system
更新于2025-09-23 15:19:57
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[IEEE 2019 24th Microoptics Conference (MOC) - Toyama, Japan (2019.11.17-2019.11.20)] 2019 24th Microoptics Conference (MOC) - Simultaneous Cross-Sectional Velocity Distribution Measurements Using Laser Doppler Velocimeter Employing 7 ?? 8 Spatial Encoding
摘要： The High Efficiency Video Coding (HEVC) standard (ITU-T H.265 and ISO/IEC 23008-2) has been developed with the main goal of providing significantly improved video compression compared with its predecessors. In order to evaluate this goal, verification tests were conducted by the Joint Collaborative Team on Video Coding of ITU-T SG 16 WP 3 and ISO/IEC JTC 1/SC 29. This paper presents the subjective and objective results of a verification test in which the performance of the new standard is compared with its highly successful predecessor, the Advanced Video Coding (AVC) video compression standard (ITU-T H.264 and ISO/IEC 14496-10). The test used video sequences with resolutions ranging from 480p up to ultra-high definition, encoded at various quality levels using the HEVC Main profile and the AVC High profile. In order to provide a clear evaluation, this paper also discusses various aspects for the analysis of the test results. The tests showed that bit rate savings of 59% on average can be achieved by HEVC for the same perceived video quality, which is higher than a bit rate saving of 44% demonstrated with the PSNR objective quality metric. However, it has been shown that the bit rates required to achieve good quality of compressed content, as well as the bit rate savings relative to AVC, are highly dependent on the characteristics of the tested content.
关键词： standards,MPEG-H Part 2,Moving Picture Experts Group (MPEG),Video Coding Experts Group (VCEG),High Efficiency Video Coding (HEVC),H.265,Advanced Video Coding (AVC),Joint Collaborative Team on Video Coding (JCT-VC),video compression
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Feasibility Analysis Using Load Profile Modeling Scenarios of Achieving Peak Shaving Using Grid-Tied PV for a Small Utility in Boone, North Carolina
摘要： The distributed Brillouin analysis of an 8.8-km-long fiber with a spatial resolution of 2 cm is presented. All 440 000 potential resolution points are addressed in the measurement. A 7-cm-long hot-spot, located toward the output end of the pump wave, is properly identified in the experiment. The experimental error in the estimate of the local values of the Brillouin frequency shift is ±3.5 MHz. The analysis is based on the simultaneous generation and analysis of Brillouin interaction in more than 2000 correlation peaks, induced by periodic phase modulation of the pump and signal waves. The Brillouin amplifications at individual peaks are resolved using radar-like coding of pump wave magnitude by a 10000 bit-long aperiodic sequence, and postdetection compression at the receiver end. Extensive numerical simulations of the Brillouin interactions over kilometers of fiber with centimeter resolution are reported as well. The results are at the state of the art for high-resolution distributed Brillouin sensors.
关键词： All-optical signal processing,fiber-optic sensors,correlation-domain analysis,stimulated Brillouin scattering,distributed fiber sensors,sequence compression
更新于2025-09-23 15:19:57
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[IEEE 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Chicago, IL, USA (2019.6.16-2019.6.21)] 2019 IEEE 46th Photovoltaic Specialists Conference (PVSC) - Observation of Dislocations in Graded Buffer Layers of IMM Single Junction InGaAs Solar Cells by Two-Photon Excitation Photoluminescence
摘要： In binary classi?cation, two-way confusion matrices, with corresponding measures, such as sensitivity and speci?city, have become so ubiquitous that those who review results may not realize there are other and more realistic ways to visualize data. This is, particularly, true when risk and reward considerations are important. The approach suggested here proposes that classi?cation need not offer a conclusion on every instance within a data set. If an algorithm ?nds instances (e.g., patient cases in a medical data set) in which attributes pertaining to a patient’s disease offer zero to nil information, there should be no classi?cation offered. From the physician’s perspective, disclosure of nil information should be welcome because it might prevent potentially harmful treatment. It follows from this that the developer of a classi?er can provide summary results amendable for helping the consumer decide whether or not it is prudent to pass or act (commission versus omission). It is not always about balancing sensitivity and speci?city in all cases, but optimizing action on some cases. The explanation is centered on John Kelly’s link of gambling with Shannon information theory. In addition, Graham’s margin of safety, Bernoulli’s utiles, and Hippocratic Oath are important. An example problem is provided using a Netherlands Cancer Institute breast cancer data set. Recurrence score, a popular molecular-based assay for breast cancer prognosis, was found to have an uninformative zone. The uninformative subset had been grouped with positive results to garner higher sensitivity. Yet, because of a positive result, patients might be advised to undergo potentially harmful treatment in the absence of useful information.
关键词： data compression,cancer,clinical diagnosis,sensitivity and speci?city,Data analysis,genetic expression,entropy
更新于2025-09-23 15:19:57
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Threshold decrease and output-power improvement in dual-loss Q-switched laser based on few-layer WTe<sub>2</sub> saturable absorber
摘要： A dual-loss Q-switched laser was realized by applying a home-made 2.5 nm-thick WTe2 to an acoustic-optic (AO) modulated laser. Besides conventional pulse compression, the participation of WTe2 could obviously improve the average output power by 29.6% and reduce the laser threshold by 20%, even with the introduced 8% nonsaturable loss. The average-output-power improvement and pulse compression in this dual-loss modulated laser resulted in a 113.7% increase of peak power. According to the measured spectra of laser and photoluminescence of WTe2, the laser-induced excitonic light-emission may be the reason of this laser gain.
关键词： WTe2 saturable absorber,laser threshold decrease,pulse compression,output-power improvement,dual-loss Q-switched laser
更新于2025-09-23 15:19:57
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[IEEE 2018 IEEE 7th Global Conference on Consumer Electronics (GCCE) - Nara, Japan (2018.10.9-2018.10.12)] 2018 IEEE 7th Global Conference on Consumer Electronics (GCCE) - Accelerating Data Loading for Photo-Based Augmented Reality on Web Browser
摘要： A photo-based augmented reality (Photo AR) system is an AR system that uses photographic images instead of computer graphics of three-dimensional models. Photo AR can display realistic AR views to users, but it requires large disk space due to its many images. Although all images can be significantly compressed into one video format file, the decoding and memory storage process are time-consuming. In this study, we propose a method to accelerate data loading for Photo AR operating on a web browser in a mobile device. The experimental results demonstrate the effectiveness of our method.
关键词： Web browser,Data compression,Photo AR,Augmented Reality
更新于2025-09-23 15:19:57